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Axel Cloeckaert - One of the best experts on this subject based on the ideXlab platform.

  • Multidrug resistance Salmonella Genomic Island 1 in a Morganella morganii subsp. morganii human clinical isolate from France
    MSphere, 2017
    Co-Authors: Eliette Schultz, Axel Cloeckaert, Olivier Barraud, Jean Yves Madec, Marisa Haenni, Marie-cécile Ploy, Benoit Doublet
    Abstract:

    Salmonella Genomic Island 1 (SGI1) is a multidrug resistance integrative mobilizable element that harbors a great diversity of antimicrobial resistance gene clusters described in numerous Salmonella enterica serovars and also in Proteus mirabilis. A serious threat to public health was revealed in the recent description in P. mirabilis of a SGI1-derivative multidrug resistance Island named PGI1 (Proteus Genomic Island 1) carrying extended-spectrum-β-lactamase (ESBL) and metallo-β-lactamase resistance genes, blaVEB-6 and blaNDM-1, respectively. Here, we report the first description of Salmonella Genomic Island 1 (SGI1) in a multidrug-resistant clinical Morganella morganii subsp. morganii strain isolated from a patient in France in 2013. Complete-genome sequencing of the strain revealed SGI1 variant SGI1-L carrying resistance genes dfrA15, floR, tetA(G), blaPSE-1 (now referred to as blaCARB-2), and sul1, conferring resistance to trimethoprim, phenicols, tetracyclines, amoxicillin, and sulfonamides, respectively. The SGI1-L variant was integrated into the usual chromosome-specific integration site at the 3′ end of the trmE gene. Beyond Salmonella enterica and Proteus mirabilis, the SGI1 integrative mobilizable element may thus also disseminate its multidrug resistance phenotype in another genus belonging to the Proteae tribe of the family Enterobacteriaceae.

  • the salmonella Genomic Island 1 is specifically mobilized in trans by the inca c multidrug resistance plasmid family
    PLOS ONE, 2010
    Co-Authors: Gregory Douard, Karine Praud, Axel Cloeckaert, Benoit Doublet
    Abstract:

    Background The Salmonella Genomic Island 1 (SGI1) is a Salmonella enterica-derived integrative mobilizable element (IME) containing various complex multiple resistance integrons identified in several S. enterica serovars and in Proteus mirabilis. Previous studies have shown that SGI1 transfers horizontally by in trans mobilization in the presence of the IncA/C conjugative helper plasmid pR55. Methodology/Principal Findings Here, we report the ability of different prevalent multidrug resistance (MDR) plasmids including extended-spectrum β-lactamase (ESBL) gene-carrying plasmids to mobilize the multidrug resistance Genomic Island SGI1. Through conjugation experiments, none of the 24 conjugative plasmids tested of the IncFI, FII, HI2, I1, L/M, N, P incompatibility groups were able to mobilize SGI1 at a detectable level (transfer frequency <10−9). In our collection, ESBL gene-carrying plasmids were mainly from the IncHI2 and I1 groups and thus were unable to mobilize SGI1. However, the horizontal transfer of SGI1 was shown to be specifically mediated by conjugative helper plasmids of the broad-host-range IncA/C incompatibility group. Several conjugative IncA/C MDR plasmids as well as the sequenced IncA/C reference plasmid pRA1 of 143,963 bp were shown to mobilize in trans SGI1 from a S. enterica donor to the Escherichia coli recipient strain. Depending on the IncA/C plasmid used, the conjugative transfer of SGI1 occurred at frequencies ranging from 10−3 to 10−6 transconjugants per donor. Of particular concern, some large IncA/C MDR plasmids carrying the extended-spectrum cephalosporinase blaCMY-2 gene were shown to mobilize in trans SGI1. Conclusions/Significance The ability of the IncA/C MDR plasmid family to mobilize SGI1 could contribute to its spread by horizontal transfer among enteric pathogens. Moreover, the increasing prevalence of IncA/C plasmids in MDR S. enterica isolates worldwide has potential implications for the epidemic success of the antibiotic resistance Genomic Island SGI1 and its close derivatives.

  • association of is26 composite transposons and complex in4 type integrons generates novel multidrug resistance loci in salmonella Genomic Island 1
    Journal of Antimicrobial Chemotherapy, 2008
    Co-Authors: Benoit Doublet, Francoisxavier Weill, Karine Praud, Axel Cloeckaert
    Abstract:

    Received 25 September 2008; returned 4 November 2008; revised 13 November 2008; accepted 17 November 2008 Objectives: Clinical isolates of Salmonella enterica serovar Haifa and Newport, which displayed extended multidrug resistance phenotypes, were investigated for the presence of Salmonella Genomic Island 1 (SGI1) and the genetic organization of its antibiotic resistance gene clusters. Methods: The S. enterica strains were isolated from humans in France in 2003 and 2004. Antibiotic susceptibility tests and various molecular techniques were used for detection and characterization of SGI1. Results: We identified SGI1 integrated in the 3 0 end of the chromosomal thdF gene in six multidrugresistant serovar Haifa and Newport strains. Two strains, of serovar Haifa and Newport, harboured the previously described SGI1-H variant. A new variant of the novel SGI1-Ks group, named SGI1-K6, revealed IS26-mediated rearrangements of the antibiotic resistance gene cluster in two serovar Newport strains. Two other serovar Newport strains harboured the SGI1-L complex class 1 integron containing the dfrA15 and blaPSE-1 resistance gene cassettes. In addition, these variants of SGI1 also contained large IS26-composite transposons inserted by a transposition event in the SGI1 backbone. These IS26-composite transposons showed a similar genetic structure to the SGI1-K variants containing an In4-type integron, a mercury resistance operon and parts of Tn1721 and Tn5393. These extended resistance gene clusters containing up to 10 antibiotic resistance genes were named SGI1-L1 and -L2. Conclusions: The serovar Haifa represents the 16th S. enterica serovar in which SGI1 has been identified. The Genomic Island SGI1 appears to be a hotspot of acquisition of antibiotic resistance genes by the transposition of In4-type integrons and large IS26-composite transposons.

  • novel insertion sequence and transposon mediated genetic rearrangements in Genomic Island sgi1 of salmonella enterica serovar kentucky
    Antimicrobial Agents and Chemotherapy, 2008
    Co-Authors: Jeanmarc Collard, Benoit Doublet, Francoisxavier Weill, Karine Praud, Sophie Bertrand, Axel Cloeckaert
    Abstract:

    Salmonella Genomic Island 1 (SGI1) is an integrative mobilizable element that harbors a multidrug resistance (MDR) gene cluster. Since its identification in epidemic Salmonella enterica serovar Typhimurium DT104 strains, variant SGI1 MDR gene clusters conferring different MDR phenotypes have been identified in several S. enterica serovars and classified as SGI1-A to -O. A study was undertaken to characterize SGI1 from serovar Kentucky strains isolated from travelers returning from Africa. Several strains tested were found to contain the partially characterized variant SGI1-K, recently described in a serovar Kentucky strain isolated in Australia. This variant contained only one cassette array, aac(3)-Id-aadA7, and an adjacent mercury resistance module. Here, the uncharacterized part of SGI1-K was sequenced. Downstream of the mer module similar to that found in Tn21, a mosaic genetic structure was found, comprising (i) part of Tn1721 containing the tetracycline resistance genes tetR and tet(A); (ii) part of Tn5393 containing the streptomycin resistance genes strAB, IS1133, and a truncated tnpR gene; and (iii) a Tn3-like region containing the tnpR gene and the β-lactamase blaTEM-1 gene flanked by two IS26 elements in opposite orientations. The rightmost IS26 element was shown to be inserted into the S044 open reading frame of the SGI1 backbone. This variant MDR region was named SGI1-K1 according to the previously described variant SGI1-K. Other SGI1-K MDR regions due to different IS26 locations, inversion, and partial deletions were characterized and named SGI1-K2 to -K5. Two new SGI1 variants named SGI1-P1 and -P2 contained only the Tn3-like region comprising the β-lactamase blaTEM-1 gene flanked by the two IS26 elements inserted into the SGI1 backbone. Three other new variants harbored only one IS26 element inserted in place of the MDR region of SGI1 and were named SGI1-Q1 to -Q3. Thus, in serovar Kentucky, the SGI1 MDR region undergoes recombinational and insertional events of transposon and insertion sequences, resulting in a higher diversity of MDR gene clusters than previously reported and consequently a higher diversity of MDR phenotypes.

  • secondary chromosomal attachment site and tandem integration of the mobilizable salmonella Genomic Island 1
    PLOS ONE, 2008
    Co-Authors: Benoit Doublet, Michael R Mulvey, George R Golding, Axel Cloeckaert
    Abstract:

    Background The Salmonella Genomic Island 1 is an integrative mobilizable element (IME) originally identified in epidemic multidrug-resistant Salmonella enterica serovar Typhimurium (S. Typhimurium) DT104. SGI1 contains a complex integron, which confers various multidrug resistance phenotypes due to its genetic plasticity. Previous studies have shown that SGI1 integrates site-specifically into the S. enterica, Escherichia coli, or Proteus mirabilis chromosome at the 3′ end of thdF gene (attB site). Methodology/Principal Findings Here, we report the transfer of SGI1 to a ΔthdF mutant of S. Typhimurium LT2. In the absence of thdF, the frequency of transconjugant formation was reduced by around thirty times of magnitude. Through DNA sequencing SGI1 was shown to integrate specifically into a secondary attachment site (2nd attB), which is located in the intergenic region between the chromosomal sodB and purR genes. At this 2nd attB site, we found that a significant fraction of SGI1 transconjugants (43% of wild type and 100% of ΔthdF mutant) contained tandem SGI1 arrays. Moreover, in wild type S. Typhimurium LT2 transconjugants, SGI1 integrated into both attachment sites, i.e., thdF and sodB-purR. The formation of SGI1 tandem arrays occurred in both specific attB sites. There was heterogeneity in the size of the SGI1 tandem arrays detected in single transconjugant colonies. Some arrays consisted as far as six SGI1s arranged in tandem. These tandem arrays were shown to persist during serial passages with or without antibiotic selection pressure. Conclusions/Significance The ability of integration into two distinct chromosomal sites and tandem array formation of SGI1 could contribute to its spread and persistence. The existence of a secondary attachment site in the Salmonella chromosome has potential implications for the mobility of SGI1, which may integrate in other attachment sites of other bacterial pathogens that do not possess the 1st or 2nd specific SGI1 attB sites of Salmonella.

Benoit Doublet - One of the best experts on this subject based on the ideXlab platform.

  • Multidrug resistance Salmonella Genomic Island 1 in a Morganella morganii subsp. morganii human clinical isolate from France
    MSphere, 2017
    Co-Authors: Eliette Schultz, Axel Cloeckaert, Olivier Barraud, Jean Yves Madec, Marisa Haenni, Marie-cécile Ploy, Benoit Doublet
    Abstract:

    Salmonella Genomic Island 1 (SGI1) is a multidrug resistance integrative mobilizable element that harbors a great diversity of antimicrobial resistance gene clusters described in numerous Salmonella enterica serovars and also in Proteus mirabilis. A serious threat to public health was revealed in the recent description in P. mirabilis of a SGI1-derivative multidrug resistance Island named PGI1 (Proteus Genomic Island 1) carrying extended-spectrum-β-lactamase (ESBL) and metallo-β-lactamase resistance genes, blaVEB-6 and blaNDM-1, respectively. Here, we report the first description of Salmonella Genomic Island 1 (SGI1) in a multidrug-resistant clinical Morganella morganii subsp. morganii strain isolated from a patient in France in 2013. Complete-genome sequencing of the strain revealed SGI1 variant SGI1-L carrying resistance genes dfrA15, floR, tetA(G), blaPSE-1 (now referred to as blaCARB-2), and sul1, conferring resistance to trimethoprim, phenicols, tetracyclines, amoxicillin, and sulfonamides, respectively. The SGI1-L variant was integrated into the usual chromosome-specific integration site at the 3′ end of the trmE gene. Beyond Salmonella enterica and Proteus mirabilis, the SGI1 integrative mobilizable element may thus also disseminate its multidrug resistance phenotype in another genus belonging to the Proteae tribe of the family Enterobacteriaceae.

  • the salmonella Genomic Island 1 is specifically mobilized in trans by the inca c multidrug resistance plasmid family
    PLOS ONE, 2010
    Co-Authors: Gregory Douard, Karine Praud, Axel Cloeckaert, Benoit Doublet
    Abstract:

    Background The Salmonella Genomic Island 1 (SGI1) is a Salmonella enterica-derived integrative mobilizable element (IME) containing various complex multiple resistance integrons identified in several S. enterica serovars and in Proteus mirabilis. Previous studies have shown that SGI1 transfers horizontally by in trans mobilization in the presence of the IncA/C conjugative helper plasmid pR55. Methodology/Principal Findings Here, we report the ability of different prevalent multidrug resistance (MDR) plasmids including extended-spectrum β-lactamase (ESBL) gene-carrying plasmids to mobilize the multidrug resistance Genomic Island SGI1. Through conjugation experiments, none of the 24 conjugative plasmids tested of the IncFI, FII, HI2, I1, L/M, N, P incompatibility groups were able to mobilize SGI1 at a detectable level (transfer frequency <10−9). In our collection, ESBL gene-carrying plasmids were mainly from the IncHI2 and I1 groups and thus were unable to mobilize SGI1. However, the horizontal transfer of SGI1 was shown to be specifically mediated by conjugative helper plasmids of the broad-host-range IncA/C incompatibility group. Several conjugative IncA/C MDR plasmids as well as the sequenced IncA/C reference plasmid pRA1 of 143,963 bp were shown to mobilize in trans SGI1 from a S. enterica donor to the Escherichia coli recipient strain. Depending on the IncA/C plasmid used, the conjugative transfer of SGI1 occurred at frequencies ranging from 10−3 to 10−6 transconjugants per donor. Of particular concern, some large IncA/C MDR plasmids carrying the extended-spectrum cephalosporinase blaCMY-2 gene were shown to mobilize in trans SGI1. Conclusions/Significance The ability of the IncA/C MDR plasmid family to mobilize SGI1 could contribute to its spread by horizontal transfer among enteric pathogens. Moreover, the increasing prevalence of IncA/C plasmids in MDR S. enterica isolates worldwide has potential implications for the epidemic success of the antibiotic resistance Genomic Island SGI1 and its close derivatives.

  • association of is26 composite transposons and complex in4 type integrons generates novel multidrug resistance loci in salmonella Genomic Island 1
    Journal of Antimicrobial Chemotherapy, 2008
    Co-Authors: Benoit Doublet, Francoisxavier Weill, Karine Praud, Axel Cloeckaert
    Abstract:

    Received 25 September 2008; returned 4 November 2008; revised 13 November 2008; accepted 17 November 2008 Objectives: Clinical isolates of Salmonella enterica serovar Haifa and Newport, which displayed extended multidrug resistance phenotypes, were investigated for the presence of Salmonella Genomic Island 1 (SGI1) and the genetic organization of its antibiotic resistance gene clusters. Methods: The S. enterica strains were isolated from humans in France in 2003 and 2004. Antibiotic susceptibility tests and various molecular techniques were used for detection and characterization of SGI1. Results: We identified SGI1 integrated in the 3 0 end of the chromosomal thdF gene in six multidrugresistant serovar Haifa and Newport strains. Two strains, of serovar Haifa and Newport, harboured the previously described SGI1-H variant. A new variant of the novel SGI1-Ks group, named SGI1-K6, revealed IS26-mediated rearrangements of the antibiotic resistance gene cluster in two serovar Newport strains. Two other serovar Newport strains harboured the SGI1-L complex class 1 integron containing the dfrA15 and blaPSE-1 resistance gene cassettes. In addition, these variants of SGI1 also contained large IS26-composite transposons inserted by a transposition event in the SGI1 backbone. These IS26-composite transposons showed a similar genetic structure to the SGI1-K variants containing an In4-type integron, a mercury resistance operon and parts of Tn1721 and Tn5393. These extended resistance gene clusters containing up to 10 antibiotic resistance genes were named SGI1-L1 and -L2. Conclusions: The serovar Haifa represents the 16th S. enterica serovar in which SGI1 has been identified. The Genomic Island SGI1 appears to be a hotspot of acquisition of antibiotic resistance genes by the transposition of In4-type integrons and large IS26-composite transposons.

  • novel insertion sequence and transposon mediated genetic rearrangements in Genomic Island sgi1 of salmonella enterica serovar kentucky
    Antimicrobial Agents and Chemotherapy, 2008
    Co-Authors: Jeanmarc Collard, Benoit Doublet, Francoisxavier Weill, Karine Praud, Sophie Bertrand, Axel Cloeckaert
    Abstract:

    Salmonella Genomic Island 1 (SGI1) is an integrative mobilizable element that harbors a multidrug resistance (MDR) gene cluster. Since its identification in epidemic Salmonella enterica serovar Typhimurium DT104 strains, variant SGI1 MDR gene clusters conferring different MDR phenotypes have been identified in several S. enterica serovars and classified as SGI1-A to -O. A study was undertaken to characterize SGI1 from serovar Kentucky strains isolated from travelers returning from Africa. Several strains tested were found to contain the partially characterized variant SGI1-K, recently described in a serovar Kentucky strain isolated in Australia. This variant contained only one cassette array, aac(3)-Id-aadA7, and an adjacent mercury resistance module. Here, the uncharacterized part of SGI1-K was sequenced. Downstream of the mer module similar to that found in Tn21, a mosaic genetic structure was found, comprising (i) part of Tn1721 containing the tetracycline resistance genes tetR and tet(A); (ii) part of Tn5393 containing the streptomycin resistance genes strAB, IS1133, and a truncated tnpR gene; and (iii) a Tn3-like region containing the tnpR gene and the β-lactamase blaTEM-1 gene flanked by two IS26 elements in opposite orientations. The rightmost IS26 element was shown to be inserted into the S044 open reading frame of the SGI1 backbone. This variant MDR region was named SGI1-K1 according to the previously described variant SGI1-K. Other SGI1-K MDR regions due to different IS26 locations, inversion, and partial deletions were characterized and named SGI1-K2 to -K5. Two new SGI1 variants named SGI1-P1 and -P2 contained only the Tn3-like region comprising the β-lactamase blaTEM-1 gene flanked by the two IS26 elements inserted into the SGI1 backbone. Three other new variants harbored only one IS26 element inserted in place of the MDR region of SGI1 and were named SGI1-Q1 to -Q3. Thus, in serovar Kentucky, the SGI1 MDR region undergoes recombinational and insertional events of transposon and insertion sequences, resulting in a higher diversity of MDR gene clusters than previously reported and consequently a higher diversity of MDR phenotypes.

  • secondary chromosomal attachment site and tandem integration of the mobilizable salmonella Genomic Island 1
    PLOS ONE, 2008
    Co-Authors: Benoit Doublet, Michael R Mulvey, George R Golding, Axel Cloeckaert
    Abstract:

    Background The Salmonella Genomic Island 1 is an integrative mobilizable element (IME) originally identified in epidemic multidrug-resistant Salmonella enterica serovar Typhimurium (S. Typhimurium) DT104. SGI1 contains a complex integron, which confers various multidrug resistance phenotypes due to its genetic plasticity. Previous studies have shown that SGI1 integrates site-specifically into the S. enterica, Escherichia coli, or Proteus mirabilis chromosome at the 3′ end of thdF gene (attB site). Methodology/Principal Findings Here, we report the transfer of SGI1 to a ΔthdF mutant of S. Typhimurium LT2. In the absence of thdF, the frequency of transconjugant formation was reduced by around thirty times of magnitude. Through DNA sequencing SGI1 was shown to integrate specifically into a secondary attachment site (2nd attB), which is located in the intergenic region between the chromosomal sodB and purR genes. At this 2nd attB site, we found that a significant fraction of SGI1 transconjugants (43% of wild type and 100% of ΔthdF mutant) contained tandem SGI1 arrays. Moreover, in wild type S. Typhimurium LT2 transconjugants, SGI1 integrated into both attachment sites, i.e., thdF and sodB-purR. The formation of SGI1 tandem arrays occurred in both specific attB sites. There was heterogeneity in the size of the SGI1 tandem arrays detected in single transconjugant colonies. Some arrays consisted as far as six SGI1s arranged in tandem. These tandem arrays were shown to persist during serial passages with or without antibiotic selection pressure. Conclusions/Significance The ability of integration into two distinct chromosomal sites and tandem array formation of SGI1 could contribute to its spread and persistence. The existence of a secondary attachment site in the Salmonella chromosome has potential implications for the mobility of SGI1, which may integrate in other attachment sites of other bacterial pathogens that do not possess the 1st or 2nd specific SGI1 attB sites of Salmonella.

Michael R Mulvey - One of the best experts on this subject based on the ideXlab platform.

  • serratia marcescens harbouring sme type class a carbapenemases in canada and the presence of blasme on a novel Genomic Island smargi1 1
    Journal of Antimicrobial Chemotherapy, 2014
    Co-Authors: Laura F Mataseje, David A Boyd, J Delport, L Hoang, Miguel Imperial, Brigitte Lefebvre, M Kuhn, P Van Caeseele, Barbara M Willey, Michael R Mulvey
    Abstract:

    OBJECTIVES An increasing prevalence since 2010 of Serratia marcescens harbouring the Ambler class A carbapenemase SME prompted us to further characterize these isolates. METHODS Isolates harbouring bla(SME) were identified by PCR and sequencing. Phenotypic analysis for carbapenemase activity was carried out by a modified Hodge test and a modified Carba NP test. Antimicrobial susceptibilities were determined by Etest and Vitek 2. Typing was by PFGE of macrorestriction digests. Whole-genome sequencing of three isolates was carried out to characterize the Genomic region harbouring the bla(SME)-type genes. RESULTS All S. marcescens harbouring SME-type enzymes could be detected using a modified Carba NP test. Isolates harbouring bla(SME) were resistant to penicillins and carbapenems, but remained susceptible to third-generation cephalosporins, as well as fluoroquinolones and trimethoprim/sulfamethoxazole. Isolates exhibited diverse genetic backgrounds, though 57% of isolates were found in three clusters. Analysis of whole-genome sequence data from three isolates revealed that the bla(SME) gene occurred in a novel cryptic prophage Genomic Island, SmarGI1-1. CONCLUSIONS There has been an increasing occurrence of S. marcescens harbouring bla(SME) in Canada since 2010. The bla(SME) gene was found on a Genomic Island, SmarGI1-1, that can be excised and circularized, which probably contributes to its dissemination amongst S. marcescens.

  • secondary chromosomal attachment site and tandem integration of the mobilizable salmonella Genomic Island 1
    PLOS ONE, 2008
    Co-Authors: Benoit Doublet, Michael R Mulvey, George R Golding, Axel Cloeckaert
    Abstract:

    Background The Salmonella Genomic Island 1 is an integrative mobilizable element (IME) originally identified in epidemic multidrug-resistant Salmonella enterica serovar Typhimurium (S. Typhimurium) DT104. SGI1 contains a complex integron, which confers various multidrug resistance phenotypes due to its genetic plasticity. Previous studies have shown that SGI1 integrates site-specifically into the S. enterica, Escherichia coli, or Proteus mirabilis chromosome at the 3′ end of thdF gene (attB site). Methodology/Principal Findings Here, we report the transfer of SGI1 to a ΔthdF mutant of S. Typhimurium LT2. In the absence of thdF, the frequency of transconjugant formation was reduced by around thirty times of magnitude. Through DNA sequencing SGI1 was shown to integrate specifically into a secondary attachment site (2nd attB), which is located in the intergenic region between the chromosomal sodB and purR genes. At this 2nd attB site, we found that a significant fraction of SGI1 transconjugants (43% of wild type and 100% of ΔthdF mutant) contained tandem SGI1 arrays. Moreover, in wild type S. Typhimurium LT2 transconjugants, SGI1 integrated into both attachment sites, i.e., thdF and sodB-purR. The formation of SGI1 tandem arrays occurred in both specific attB sites. There was heterogeneity in the size of the SGI1 tandem arrays detected in single transconjugant colonies. Some arrays consisted as far as six SGI1s arranged in tandem. These tandem arrays were shown to persist during serial passages with or without antibiotic selection pressure. Conclusions/Significance The ability of integration into two distinct chromosomal sites and tandem array formation of SGI1 could contribute to its spread and persistence. The existence of a secondary attachment site in the Salmonella chromosome has potential implications for the mobility of SGI1, which may integrate in other attachment sites of other bacterial pathogens that do not possess the 1st or 2nd specific SGI1 attB sites of Salmonella.

  • salmonella Genomic Island 1 sgi1 variant sgi1 i and new variant sgi1 o in proteus mirabilis clinical and food isolates from china
    Antimicrobial Agents and Chemotherapy, 2008
    Co-Authors: David A Boyd, Xiaolu Shi, Qinghua Hu, Lai King Ng, Benoit Doublet, Axel Cloeckaert, Michael R Mulvey
    Abstract:

    Salmonella Genomic Island 1 (SGI1) and variants (SGI1-I and the new variant SGI1-O) were mapped in five strains of Proteus mirabilis isolated from humans and food in China. Sequencing showed that SGI1 and variants were integrated at the 3′ end of the chromosomal thdF gene as previously described for Salmonella strains.

  • the genetics of salmonella Genomic Island 1
    Microbes and Infection, 2006
    Co-Authors: Michael R Mulvey, David A Boyd, Benoit Doublet, Adam B Olson, Axel Cloeckaert
    Abstract:

    Multidrug-resistant Salmonella enterica serovar Typhimurium phage type DT104, resistant to ampicillin, chloramphenicol/florfenicol, streptomycin, sulfonamides, and tetracycline, has disseminated worldwide. The resistance genes reside on the 43-kb Salmonella Genomic Island 1 (SGI1), which is transferable. Drug-resistant variants of SGI1 have been identified in numerous serotypes. Strains harboring SGI1 may be more virulent and have a tendency to rapidly disseminate.

  • the salmonella Genomic Island 1 is an integrative mobilizable element
    Molecular Microbiology, 2005
    Co-Authors: Benoit Doublet, David A Boyd, Michael R Mulvey, Axel Cloeckaert
    Abstract:

    Summary Salmonella Genomic Island 1 (SGI1) is a Genomic Island containing an antibiotic resistance gene clus- ter identified in several Salmonella enterica serovars. The SGI1 antibiotic resistance gene cluster, which is a complex class 1 integron, confers the common mul- tidrug resistance phenotype of epidemic S. enterica Typhimurium DT104. The SGI1 occurrence in S. enterica serovars Typhimurium, Agona, Paratyphi B, Albany, Meleagridis and Newport indicates the hor- izontal transfer potential of SGI1. Here, we report that SGI1 could be conjugally transferred from S. enterica donor strains to non-SGI1 S. enterica and Escherichia coli recipient strains where it integrated into the recip- ient chromosome in a site-specific manner. First, an extrachromosomal circular form of SGI1 was identi- fied by PCR which forms through a specific recombi- nation of the left and right ends of the integrated SGI1. Chromosomal excision of SGI1 was found to require SGI1-encoded integrase which presents similarities to the lambdoid integrase family. Second, the conju- gal transfer of SGI1 required the presence of a helper plasmid. The conjugative IncC plasmid R55 could thus mobilize in trans SGI1 which was transferred from the donor to the recipient strains. By this way, the conjugal transfer of SGI1 occurred at a frequency of 10 - 5 - 10 - 6 transconjugants per donor. No transcon- jugants could be obtained for the SGI1 donor lacking the int integrase gene. Third, chromosomal integra- tion of SGI1 occurred via a site-specific recombina- tion between a 18 bp sequence found in the circular form of SGI1 and a similar 18 bp sequence at the 3 ¢¢ end of thdF gene in the S. enterica and E. coli chro- mosome. SGI1 appeared to be transmissible only in the presence of additional conjugative functions pro- vided in trans . SGI1 can thus be classified within the group of integrative mobilizable elements (IMEs).

David A Boyd - One of the best experts on this subject based on the ideXlab platform.

  • serratia marcescens harbouring sme type class a carbapenemases in canada and the presence of blasme on a novel Genomic Island smargi1 1
    Journal of Antimicrobial Chemotherapy, 2014
    Co-Authors: Laura F Mataseje, David A Boyd, J Delport, L Hoang, Miguel Imperial, Brigitte Lefebvre, M Kuhn, P Van Caeseele, Barbara M Willey, Michael R Mulvey
    Abstract:

    OBJECTIVES An increasing prevalence since 2010 of Serratia marcescens harbouring the Ambler class A carbapenemase SME prompted us to further characterize these isolates. METHODS Isolates harbouring bla(SME) were identified by PCR and sequencing. Phenotypic analysis for carbapenemase activity was carried out by a modified Hodge test and a modified Carba NP test. Antimicrobial susceptibilities were determined by Etest and Vitek 2. Typing was by PFGE of macrorestriction digests. Whole-genome sequencing of three isolates was carried out to characterize the Genomic region harbouring the bla(SME)-type genes. RESULTS All S. marcescens harbouring SME-type enzymes could be detected using a modified Carba NP test. Isolates harbouring bla(SME) were resistant to penicillins and carbapenems, but remained susceptible to third-generation cephalosporins, as well as fluoroquinolones and trimethoprim/sulfamethoxazole. Isolates exhibited diverse genetic backgrounds, though 57% of isolates were found in three clusters. Analysis of whole-genome sequence data from three isolates revealed that the bla(SME) gene occurred in a novel cryptic prophage Genomic Island, SmarGI1-1. CONCLUSIONS There has been an increasing occurrence of S. marcescens harbouring bla(SME) in Canada since 2010. The bla(SME) gene was found on a Genomic Island, SmarGI1-1, that can be excised and circularized, which probably contributes to its dissemination amongst S. marcescens.

  • salmonella Genomic Island 1 sgi1 variant sgi1 i and new variant sgi1 o in proteus mirabilis clinical and food isolates from china
    Antimicrobial Agents and Chemotherapy, 2008
    Co-Authors: David A Boyd, Xiaolu Shi, Qinghua Hu, Lai King Ng, Benoit Doublet, Axel Cloeckaert, Michael R Mulvey
    Abstract:

    Salmonella Genomic Island 1 (SGI1) and variants (SGI1-I and the new variant SGI1-O) were mapped in five strains of Proteus mirabilis isolated from humans and food in China. Sequencing showed that SGI1 and variants were integrated at the 3′ end of the chromosomal thdF gene as previously described for Salmonella strains.

  • the genetics of salmonella Genomic Island 1
    Microbes and Infection, 2006
    Co-Authors: Michael R Mulvey, David A Boyd, Benoit Doublet, Adam B Olson, Axel Cloeckaert
    Abstract:

    Multidrug-resistant Salmonella enterica serovar Typhimurium phage type DT104, resistant to ampicillin, chloramphenicol/florfenicol, streptomycin, sulfonamides, and tetracycline, has disseminated worldwide. The resistance genes reside on the 43-kb Salmonella Genomic Island 1 (SGI1), which is transferable. Drug-resistant variants of SGI1 have been identified in numerous serotypes. Strains harboring SGI1 may be more virulent and have a tendency to rapidly disseminate.

  • the salmonella Genomic Island 1 is an integrative mobilizable element
    Molecular Microbiology, 2005
    Co-Authors: Benoit Doublet, David A Boyd, Michael R Mulvey, Axel Cloeckaert
    Abstract:

    Summary Salmonella Genomic Island 1 (SGI1) is a Genomic Island containing an antibiotic resistance gene clus- ter identified in several Salmonella enterica serovars. The SGI1 antibiotic resistance gene cluster, which is a complex class 1 integron, confers the common mul- tidrug resistance phenotype of epidemic S. enterica Typhimurium DT104. The SGI1 occurrence in S. enterica serovars Typhimurium, Agona, Paratyphi B, Albany, Meleagridis and Newport indicates the hor- izontal transfer potential of SGI1. Here, we report that SGI1 could be conjugally transferred from S. enterica donor strains to non-SGI1 S. enterica and Escherichia coli recipient strains where it integrated into the recip- ient chromosome in a site-specific manner. First, an extrachromosomal circular form of SGI1 was identi- fied by PCR which forms through a specific recombi- nation of the left and right ends of the integrated SGI1. Chromosomal excision of SGI1 was found to require SGI1-encoded integrase which presents similarities to the lambdoid integrase family. Second, the conju- gal transfer of SGI1 required the presence of a helper plasmid. The conjugative IncC plasmid R55 could thus mobilize in trans SGI1 which was transferred from the donor to the recipient strains. By this way, the conjugal transfer of SGI1 occurred at a frequency of 10 - 5 - 10 - 6 transconjugants per donor. No transcon- jugants could be obtained for the SGI1 donor lacking the int integrase gene. Third, chromosomal integra- tion of SGI1 occurred via a site-specific recombina- tion between a 18 bp sequence found in the circular form of SGI1 and a similar 18 bp sequence at the 3 ¢¢ end of thdF gene in the S. enterica and E. coli chro- mosome. SGI1 appeared to be transmissible only in the presence of additional conjugative functions pro- vided in trans . SGI1 can thus be classified within the group of integrative mobilizable elements (IMEs).

  • salmonella Genomic Island 1 multidrug resistance gene clusters in salmonella enterica serovar agona isolated in belgium in 1992 to 2002
    Antimicrobial Agents and Chemotherapy, 2004
    Co-Authors: Benoit Doublet, H Imberechts, Elisabeth Chaslusdancla, Patrick Butaye, David A Boyd, Michael R Mulvey, Axel Cloeckaert
    Abstract:

    Salmonella Genomic Island 1 (SGI1) harbors a multidrug resistance (MDR) gene cluster which is a complex class 1 integron. Variant SGI1 MDR gene clusters conferring different MDR profiles have also been identified in several Salmonella enterica serovars and classified as SGI1-A to -F. A retrospective study was undertaken to characterize MDR regions from serovar Agona strains harboring SGI1 isolated from poultry in Belgium between 1992 and 2002. A total of 171 serovar Agona strains, displaying resistance to at least one antibiotic, were studied for the presence of SGI1. SGI1 was detected in 94 serovar Agona strains. The most prevalent variant was SGI1-A (85%), which harbors within the SGI1 complex class 1 integron a common region (CR1) containing orf513, a putative transposase gene, adjacent to the dfrA10 trimethoprim resistance gene. A new variant SGI1 named SGI1-G was identified in two strains. It consisted of the pse-1 gene cassette, as in SGI1-B, but with additional insertion of the orf513/dfrA10 region structure. Seven strains displaying the typical SGI1 MDR profile (Ap Cm Ff Sm Sp Su Tc) showed genetic variation at the 3 end of SGI1. These strains harbored the insertion of the CR1 containing orf513 as in SGI1-A, -D, and -G. However, downstream the right end of CR1, they presented different 7.4- to 8.5-kb deletions of the SGI1 3 end that extended to the chromosomal genes yieE and yieF. These results suggest a possible role of CR1 in deletion formation, as has been reported for some insertion sequences. Pulsed-field gel electrophoresis analysis showed that all the serovar Agona SGI1-carrying strains belonged to a single clone. Thus, SGI1 is largely encountered in serovar Agona strains isolated from poultry in Belgium, the most prevalent variant being SGI1-A. SGI1 MDR region undergoes recombinational events resulting in a diversity of MDR gene clusters.

Elisabeth Chaslusdancla - One of the best experts on this subject based on the ideXlab platform.

  • variant salmonella Genomic Island 1 antibiotic resistance gene cluster containing a novel 3 n aminoglycoside acetyltransferase gene cassette aac 3 id in salmonella enterica serovar newport
    Antimicrobial Agents and Chemotherapy, 2004
    Co-Authors: Benoit Doublet, Elisabeth Chaslusdancla, Francoisxavier Weill, Laetitia Fabre, Axel Cloeckaert
    Abstract:

    Salmonella Genomic Island 1 (SGI1) harbors an antibiotic resistance gene cluster and was previously identified in the multidrug-resistant Salmonella enterica serovars Typhimurium DT104, Agona, Paratyphi B, and Albany. This antibiotic resistance gene cluster is a complex class 1 integron and most often confers resistance to ampicillin (Ap), chloramphenicol (Cm)/florfenicol (Ff), streptomycin (Sm)/spectinomycin (Sp), sulfonamides (Su), and tetracycline (Tc) (ApCmFfSmSpSuTc profile). Recently, variant SGI1 antibiotic resistance gene clusters conferring different antibiotic resistance profiles have been identified in several S. enterica serovars and were classified as SGI1-A to -G. We identified a new variant SGI1 antibiotic resistance gene cluster in two multidrug-resistant S. enterica serovar Newport strains isolated from humans in France. In these strains, the Sm/Sp resistance gene cassette aadA2 inserted at the first attI1 site was replaced by two other aminoglycoside resistance gene cassettes. The first one contains a new resistance gene encoding an AAC(3)-I aminoglycoside 3-N-acetyltransferase that confers resistance to gentamicin (Gm) and sisomicin (Sc). This gene has been named aac(3)-Id. The second one harbors the Sm/Sp resistance gene aadA7. This gene cassette replacement in the SGI1 complex integron of serovar Newport strains constitutes a new variant SGI1 antibiotic resistance gene cluster named SGI1-H. The occurrence of SGI1 in different S. enterica serovars, now including serovar Newport, strengthens the hypothesis of horizontal transfer of SGI1.

  • salmonella Genomic Island 1 multidrug resistance gene clusters in salmonella enterica serovar agona isolated in belgium in 1992 to 2002
    Antimicrobial Agents and Chemotherapy, 2004
    Co-Authors: Benoit Doublet, H Imberechts, Elisabeth Chaslusdancla, Patrick Butaye, David A Boyd, Michael R Mulvey, Axel Cloeckaert
    Abstract:

    Salmonella Genomic Island 1 (SGI1) harbors a multidrug resistance (MDR) gene cluster which is a complex class 1 integron. Variant SGI1 MDR gene clusters conferring different MDR profiles have also been identified in several Salmonella enterica serovars and classified as SGI1-A to -F. A retrospective study was undertaken to characterize MDR regions from serovar Agona strains harboring SGI1 isolated from poultry in Belgium between 1992 and 2002. A total of 171 serovar Agona strains, displaying resistance to at least one antibiotic, were studied for the presence of SGI1. SGI1 was detected in 94 serovar Agona strains. The most prevalent variant was SGI1-A (85%), which harbors within the SGI1 complex class 1 integron a common region (CR1) containing orf513, a putative transposase gene, adjacent to the dfrA10 trimethoprim resistance gene. A new variant SGI1 named SGI1-G was identified in two strains. It consisted of the pse-1 gene cassette, as in SGI1-B, but with additional insertion of the orf513/dfrA10 region structure. Seven strains displaying the typical SGI1 MDR profile (Ap Cm Ff Sm Sp Su Tc) showed genetic variation at the 3 end of SGI1. These strains harbored the insertion of the CR1 containing orf513 as in SGI1-A, -D, and -G. However, downstream the right end of CR1, they presented different 7.4- to 8.5-kb deletions of the SGI1 3 end that extended to the chromosomal genes yieE and yieF. These results suggest a possible role of CR1 in deletion formation, as has been reported for some insertion sequences. Pulsed-field gel electrophoresis analysis showed that all the serovar Agona SGI1-carrying strains belonged to a single clone. Thus, SGI1 is largely encountered in serovar Agona strains isolated from poultry in Belgium, the most prevalent variant being SGI1-A. SGI1 MDR region undergoes recombinational events resulting in a diversity of MDR gene clusters.

  • salmonella Genomic Island 1 multidrug resistance gene clusters in salmonella enterica serovar agona isolated in belgium in 1992 to 2002
    Antimicrobial Agents and Chemotherapy, 2004
    Co-Authors: Benoit Doublet, H Imberechts, Elisabeth Chaslusdancla, Patrick Butaye, David A Boyd, Michael R Mulvey, Axel Cloeckaert
    Abstract:

    Salmonella Genomic Island 1 (SGI1) harbors a multidrug resistance (MDR) gene cluster which is a complex class 1 integron. Variant SGI1 MDR gene clusters conferring different MDR profiles have also been identified in several Salmonella enterica serovars and classified as SGI1-A to -F. A retrospective study was undertaken to characterize MDR regions from serovar Agona strains harboring SGI1 isolated from poultry in Belgium between 1992 and 2002. A total of 171 serovar Agona strains, displaying resistance to at least one antibiotic, were studied for the presence of SGI1. SGI1 was detected in 94 serovar Agona strains. The most prevalent variant was SGI1-A (85%), which harbors within the SGI1 complex class 1 integron a common region (CR1) containing orf513, a putative transposase gene, adjacent to the dfrA10 trimethoprim resistance gene. A new variant SGI1 named SGI1-G was identified in two strains. It consisted of the pse-1 gene cassette, as in SGI1-B, but with additional insertion of the orf513/dfrA10 region structure. Seven strains displaying the typical SGI1 MDR profile (Ap Cm Ff Sm Sp Su Tc) showed genetic variation at the 3 end of SGI1. These strains harbored the insertion of the CR1 containing orf513 as in SGI1-A, -D, and -G. However, downstream the right end of CR1, they presented different 7.4- to 8.5-kb deletions of the SGI1 3 end that extended to the chromosomal genes yieE and yieF. These results suggest a possible role of CR1 in deletion formation, as has been reported for some insertion sequences. Pulsed-field gel electrophoresis analysis showed that all the serovar Agona SGI1-carrying strains belonged to a single clone. Thus, SGI1 is largely encountered in serovar Agona strains isolated from poultry in Belgium, the most prevalent variant being SGI1-A. SGI1 MDR region undergoes recombinational events resulting in a diversity of MDR gene clusters.

  • salmonella agona harboring Genomic Island 1 a
    Emerging Infectious Diseases, 2004
    Co-Authors: Benoit Doublet, H Imberechts, Jeanmarc Collard, Elisabeth Chaslusdancla, Patrick Butaye, Axel Cloeckaert
    Abstract:

    To the Editor: Multidrug-resistant Salmonella enterica serovar Typhimurium definitive phage type 104 has emerged during the 1980s and 1990s as a world health problem because of its implications in animal and human disease (1–3). Epidemic serovar Typhimurium definitive phage type 104 isolates are commonly resistant to ampicillin (Ap), chloramphenicol (Cm)/florfenicol (Ff), streptomycin (Sm)/spectinomycin (Sp), sulfonamides (Su), and tetracyclines (Tc) (1,3). This multidrug-resistance phenotype is conferred by an antibiotic resistance gene cluster included in a 43kb Genomic Island named Salmonella Genomic Island 1 (4). Salmonella Genomic Island 1 has been recently characterized and located between the thdF and int2 genes of the chromosome. The int2 gene is part of a retron sequence found only in serovar Typhimurium. Downstream of the retron sequence is the yidY gene, which is also found in the chromosome of other S. enterica serovars. The antibiotic resistance gene cluster of approximately 13 kb is located at the 3’ end of Salmonella Genomic Island 1 (4). All resistance genes are clustered and are bracketed by two integron structures (5,6). The first integron carries the aadA2 gene, which confers resistance to Sm and Sp. The second integron contains the β-lactamase gene pse-1, conferring resistance to Ap. Flanked by these two integron structures are the floR gene, which confers cross-resistance to Cm and Ff, and the tetracyclines-resistance genes tetR and tet(G) (5,6). Recently, Salmonella Genomic Island 1 has also been identified in other serovars of S. enterica namely Agona (4,7), Paratyphi B (8), and Albany (9), indicating the horizontal transfer potential of Salmonella Genomic Island 1. In these serovars, Salmonella Genomic Island 1 has the same chromosomal location as in serovar Typhimurium definitive phage type 104, except that they lack the retron sequence found downstream of Salmonella Genomic Island 1 (4,8,9). Moreover, six variant Salmonella Genomic Island 1 antibiotic resistance gene clusters (Salmonella Genomic Island 1-A to -F) have recently been reported for serovars Typhimurium DT104, Agona, and Albany to confer different multidrug resistance phenotypes (9,10). These clusters of genes were probably generated after chromosomal recombinational events or by antibiotic resistance gene cassette replacement in the integron structures. In particular, the dfrA10 gene coding for trimethoprim (Tm) resistance was found downstream of the pse-1 integron in a third unusual integron structure involving orf513 in the variant antibiotic resistance gene cluster called Salmonella Genomic Island 1-A (ApCmFfSmSpSuTcTm) (10). Multidrug-resistant serovar Typhimurium definitive phage type 104 was disseminated globally with several outbreaks in humans and animals. At present, in contrast to the world health problem of multidrug-resistant serovar Typhimurium definitive phage type 104, human cases of infections with other S. enterica serovars harboring Salmonella Genomic Island 1 have not yet been reported. Salmonella Genomic Island 1-multidrug-resistant serovars Agona, Paratyphi B, and Albany were isolated from different animal species and countries (7–9). In this study, we analysed the first Salmonella Genomic Island 1 positive serovar Agona strain (02/01177) isolated from a human case in Belgium. A Belgian patient, who had been infected by a multidrug-resistant serovar Agona strain was travelling to Turkey; subsequent to the multidrug-resistant serovar Agona strain, gastroenteritis developed. While in Turkey the patient sought medical care and was treated unsuccessfully with antimicrobial agents. Upon his return to Belgium, this serovar Agona strain was isolated from his stools, and he recovered after treatment with ciprofloxacin. The serovar Agona strain 02/01177 displayed the multidrug resistance profile ApCmFfSmSpSuTcTm, which suggested the possible occurrence of Salmonella Genomic Island 1-A (10). Moreover, the strain showed the same level of resistance to Ff as Salmonella Genomic Island 1 harboring S. enterica serovars (MIC of 64 µg/mL) (7–9). To assess the presence of Salmonella Genomic Island 1 and its location in the chromosome, polymerase chain reactions (PCRs) were performed using primers corresponding to the left and the right (with or without retron) Salmonella Genomic Island 1 junctions to the chromosome as described previously (4,8–10). PCR results were positive for the left junction between the thdF gene of the chromosome and the int gene of Salmonella Genomic Island 1 (4). For the right junction, PCR results were positive between open reading frame (ORF) S044 of Salmonella Genomic Island 1 and yidY gene of the chromosome. Thus, these data indicate that this serovar Agona human isolate contains Salmonella Genomic Island 1 at the same chromosomal location as in other Salmonella Genomic Island 1 positive serovars but lacks the retron sequence found to date only in serovar Typhimurium strains (4,8,9). PCR mapping of the typical antibiotic resistance genes and integrons associated with Salmonella Genomic Island 1 was realized as described previouly (4,8–10). PCR amplifications on Genomic DNA extracted from serovar Agona strain 02/01177 yielded all specific fragments of the sizes expected from DNA of serovar Agona control strain 1169SA97 harboring Salmonella Genomic Island 1-A (data not shown) (10). These PCR mapping results indicated the presence of the typical Salmonella Genomic Island 1 resistance gene cluster with the insertion of the third unusual orf513 integron structure carrying dfrA10 (8–10). These data are in accordance with the multidrug resistance phenotype of serovar Agona strain 02/01177 and indicate the presence of the variant antibiotic resistance gene cluster Salmonella Genomic Island 1-A (10). Macrorestriction analysis by pulsed-field gel electrophoresis of DNA from serovar Agona strain 02/01177 cut by XbaI or BlnI, showed that this human isolate is indistinguishable by its XbaI or BlnI macrorestriction patterns from the other multidrug-resistant Salmonella Genomic Island 1-carrying serovar Agona strains isolated from poultry in Belgium (data not shown) (7). Thus, the human serovar Agona isolate appears clonally related to those from poultry. To our knowledge, this is the first report describing a human infected by a serovar Agona strain harboring Salmonella Genomic Island 1-A. Moreover, it shows the first case where another S. enterica serovar harboring Salmonella Genomic Island 1 than the epidemic serovar Typhimurium definitive phage type 104 clone is implicated in human infection. The patient could probably have been infected before his travel to Turkey by a Salmonella Genomic Island 1-A carrying serovar Agona strain in Belgium where this type of strain is frequently isolated from poultry (Doublet et al., personal communication). This hypothesis is also supported by macrorestriction analysis, which showed that the strains from poultry and the human case-patient had identical XbaI and BlnI pulsed-field gel electrophoresis patterns and thus indicate that they are clonally related. Moreover, the patient was not in contact with poultry during his stay in Turkey and, to date, very little is known about the epidemiology of multidrug-resistant serovar Agona strains in this country. Further investigations on the epidemiology of multidrug-resistant serovar Agona strains harboring Salmonella Genomic Island 1 are warranted to avoid such strains becoming a worldwide epidemic, as was the case for multidrug-resistant serovar Typhimurium definitive phage type 104.

  • variant salmonella Genomic Island 1 antibiotic resistance gene cluster in salmonella enterica serovar albany
    Emerging Infectious Diseases, 2003
    Co-Authors: Benoit Doublet, Elisabeth Chaslusdancla, David A Boyd, Michael R Mulvey, Daniele Meunier, Renaud Lailler, Anne Brisabois, Axel Cloeckaert
    Abstract:

    Salmonella Genomic Island 1 (SGI1) contains an antibiotic resistance gene cluster and has been previously identified in multidrug-resistant Salmonella enterica serovars Typhimurium DT104, Agona, and Paratyphi B. We identified a variant SGI1 antibiotic-resistance gene cluster in a multidrug-resistant strain of S. enterica serovar Albany isolated from food fish from Thailand and imported to France. In this strain, the streptomycin resistance aadA2 gene cassette in one of the SGI1 integrons was replaced by a dfrA1 gene cassette, conferring resistance to trimethoprim and an open reading frame of unknown function. Thus, this serovar Albany strain represents the fourth S. enterica serovar in which SGI1 has been identified and the first SGI1 example where gene cassette replacement took place in one of its integron structures. The antibiotic resistance gene cluster of serovar Albany strain 7205.00 constitutes a new SGI1 variant; we propose a name of SGI1-F.