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Marja-liisa Hänninen - One of the best experts on this subject based on the ideXlab platform.

  • Sialylation of Helicobacter Bizzozeronii lipopolysaccharides modulates Toll-like receptor (TLR) 2 mediated response
    Veterinary Research, 2015
    Co-Authors: Pradeep Kumar Kondadi, Marja-liisa Hänninen, Joana Revez, Mirko Rossi
    Abstract:

    Sialic acid in lipopolysaccharides (LPS) of mucosal pathogens is known to be an important virulence factor. Few strains of Helicobacter pylori express sialyl-Lewis-X and we have reported that human and canine Helicobacter Bizzozeronii strains express sialyl-lactoseamine in their LPS. However, the role of sialyation of Helicobacter LPS in the interaction with the host cells is still unknown. In this study H. Bizzozeronii LPS is shown to activate the TLR2 in a dose and strain dependent manner in the in vitro HEK-293 cells model expressing TLR2, but not the cells expressing TLR4. These results indicate that TLR2 is the specific receptor for H. bizzozzeronii LPS, as previously described for H. pylori. To further explore the role of sialylation of H. Bizzozeronii LPS on TLR2 response, H. Bizzozeronii Δhbs2 mutant strains deficient in sialyltransferase activity were constructed by homologous recombination. LPS from H. Bizzozeronii Δhbs2 strains enhanced the NF-ĸB induction via TLR2 compared to the respective wild types, leading to the conclusion that the sialylation of H. Bizzozeronii LPS in wild-type strains may modulate host immune response.

  • Sialylation of Helicobacter Bizzozeronii lipopolysaccharides modulates Toll-like receptor (TLR) 2 mediated response
    Veterinary Research, 2015
    Co-Authors: Pradeep Kumar Kondadi, Marja-liisa Hänninen, Joana Revez, Mirko Rossi
    Abstract:

    Sialic acid in lipopolysaccharides (LPS) of mucosal pathogens is known to be an important virulence factor. Few strains of Helicobacter pylori express sialyl-Lewis-X and we have reported that human and canine Helicobacter Bizzozeronii strains express sialyl-lactoseamine in their LPS. However, the role of sialyation of Helicobacter LPS in the interaction with the host cells is still unknown. In this study H. Bizzozeronii LPS is shown to activate the TLR2 in a dose and strain dependent manner in the in vitro HEK-293 cells model expressing TLR2, but not the cells expressing TLR4. These results indicate that TLR2 is the specific receptor for H. bizzozzeronii LPS, as previously described for H. pylori. To further explore the role of sialylation of H. Bizzozeronii LPS on TLR2 response, H. Bizzozeronii Δhbs2 mutant strains deficient in sialyltransferase activity were constructed by homologous recombination. LPS from H. Bizzozeronii Δhbs2 strains enhanced the NF-ĸB induction via TLR2 compared to the respective wild types, leading to the conclusion that the sialylation of H. Bizzozeronii LPS in wild-type strains may modulate host immune response.

  • Contingency nature of Helicobacter Bizzozeronii oxygen-insensitive NAD(P)H-nitroreductase (HBZC1_00960) and its role in metronidazole resistance
    Veterinary Research, 2013
    Co-Authors: Pradeep Kumar Kondadi, Marja-liisa Hänninen, Joana Revez, Claudia Pacini, Mirko Rossi
    Abstract:

    Genomic analysis of a metronidazole resistant H. Bizzozeronii strain revealed a frame length extension of the oxygen-insensitive NAD(P)H-nitroreductase HBZC1_00960 (RdxA), associated with the disruption of the C-terminal cysteine-containing conserved region (IACLXALGK). This was the result of the extension (from C_8 to C_9) of a simple sequence cytosine repeat (SSCR) located in the 3’ of the gene. A 3' SSCR is also present in the rdxA homolog of H. heilmannii sensu stricto, but not in H. pylori . We showed that in the majority of in vitro spontaneous H. Bizzozeronii metronidazole resistant mutants, the extension of the 3′ SSCR of rdxA was the only mutation observed. In addition, we observed that H. Bizzozeronii Δ rdxA mutant strain showed the same MIC value of metronidazole observed in the spontaneous mutants. These data indicate that loss of function mutations in rdxA and in particular the disruption of the conserved region IACLXALGK is associated with reduced susceptibility to metronidazole in H. Bizzozeronii . Slipped-strand mispairing of the SSCR located in the 3′ of the H. Bizzozeronii rdxA appears to be the main mechanism. We also observed that H. Bizzozeronii acquires resistance to metronidazole at high mutation rate, and that serial passages in vitro without selection induced an increased level of susceptibility. In conclusion, contrary to what was previously described in H. pylori , the H. Bizzozeronii rdxA appears to be a contingency gene which undergoes phase variation. The contingency nature of rdxA should be carefully considered when metronidazole is used in the treatment of H. heilmannii -associated gastritis.

  • Microevolution of a zoonotic Helicobacter population colonizing the stomach of a human host before and after failed treatment.
    Genome biology and evolution, 2012
    Co-Authors: Thomas Schott, Marja-liisa Hänninen, Pradeep Kumar Kondadi, Mirko Rossi
    Abstract:

    To investigate the microevolution of Helicobacter Bizzozeronii in the human stomach, comparative genomics of antrum-derived populations, obtained 3 months before (T0) and 6 months after (T1) an unsuccessful eradication treatment, was performed. For each time point, the DNA of bacterial mass, representing the population diversity in three biopsies, was mixed in equal amounts and sequenced using Illumina technology. Polymorphic sites (PSs) were detected by mapping the reads against an isogenic reference genome, derived from a corpus isolate obtained at T0. The total numbers of PSs detected in the H. Bizzozeronii population at T0 and T1 were 128 and 223, affecting 81 and 134 coding sequences, respectively. At T0 in 91.4% of the PSs the mutation appeared at a frequency of 50% or less. On the contrary, in the majority of the PSs observed in T1 (71.3%) the mutation had a frequency >75%. Although only a minority of mutations were fixed in the antrum-derived population at T0, a certain level of allelic variability, compared with the corpus-derived reference genome, was present and most likely arose as consequence of the long-term colonization of the patient. The treatment probably induced a sudden decrease of population size, selecting a subpopulation, which acted as founder for the new population at T1 characterized by a higher number of fixed mutations. These data demonstrate that genome plasticity is an important common prerequisite among gastric Helicobacter species for adaptation to the stomach environment allowing the bacterium to evolve rapidly once a selective pressure is applied.

  • Helicobacter spp. other than H. pylori.
    Helicobacter, 2012
    Co-Authors: Mirko Rossi, Marja-liisa Hänninen
    Abstract:

    Significant advances have been made over the last 12 months in the understanding of the biology of non-H. pylori Helicobacter species (NHPH). Several studies have investigated the association between NHPH and human disease, including Crohn's disease, lithiasis, liver disease, coronary disease, gastritis, and pyoderma gangrenosum-like ulcers. Novel Helicobacter taxa were identified in new vertebrate hosts, and new methodologies in the fields of identification of Helicobacter spp. and evaluation of antibiotic resistance were described. The genome of the first human-derived gastric NHPH strain (Helicobacter Bizzozeronii CIII-1) was sequenced, and several studies elucidated functions of different genes in NHPH. A number of important investigations regarding pathogenesis and immunopathobiology of NHPH infections have been published including the description of a new urease in Helicobacter mustelae. Finally, the effects of the gut microbiota and probiotics on NHPH infections were investigated.

Freddy Haesebrouck - One of the best experts on this subject based on the ideXlab platform.

  • Gastric and enterohepatic non-Helicobacter pylori Helicobacters.
    Helicobacter, 2013
    Co-Authors: Bram Flahou, Hideo Yonezawa, Annemieke Smet, Takako Osaki, Freddy Haesebrouck, Shigeru Kamiya
    Abstract:

    A substantial number of reports published in the last year have contributed to a better understanding of both human and animal infection with non-Helicobacter pylori Helicobacter species (NHPH). Gastric infection of humans with Helicobacter suis and Helicobacter felis as well as unidentified NHPH has been described to cause a chronic gastritis and a variety of clinical symptoms, whereas enterohepatic NHPH, including Helicobacter cinaedi, Helicobacter bilis, and Helicobacter canis, have been reported to be associated with human diseases such as bacteremia, cellulitis, cutaneous diseases, and fever of unknown origin in immunocompromised hosts. In various animal species, including dogs and laboratory mice, high rates of infection with NHPH were described. For gastric NHPH, mainly H. suis and H. felis infection was studied, revealing that differences in the immune response evoked in the host do exist when compared to Helicobacter pylori. Pathogenic mechanisms of infection with Helicobacter pullorum, H. bilis, and Helicobacter hepaticus were investigated, as well as immune responses involved in H. bilis-, Helicobacter typhlonius-, and H. hepaticus-induced intestinal inflammation. Complete genome sequences of Helicobacter heilmannii strain ASB1 and a H. cinaedi strain isolated in a case of human bacteremia were published, as well as comparative genomics of a human-derived Helicobacter Bizzozeronii strain and proteome or secretome analyses for H. hepaticus and Helicobacter trogontum, respectively. Molecular analysis has revealed a function for type VI secretion systems of H. hepaticus and H. pullorum, the Helicobacter mustelae iron urease, and several other functional components of NHPH. In each section of this chapter, new findings on gastric NHPH will first be discussed, followed by those on enterohepatic Helicobacter species.

  • Helicobacter heilmannii sp nov isolated from feline gastric mucosa
    International Journal of Systematic and Evolutionary Microbiology, 2012
    Co-Authors: Annemieke Smet, Richard Ducatelle, Katharina Dherde, Bram Flahou, Ilse Cleenwerck, Peter Vandamme, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Three Gram-negative, microaerophilic bacteria, strains ASB1T, ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1T, ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter Bizzozeronii, ‘Candidatus Helicobacter heilmannii’, Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1T, ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1T, ASB2 and ASB3 showed approximately 91 % similarity to those of ‘Candidatus Helicobacter heilmannii’. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1T, ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to ‘Candidatus Helicobacter heilmannii’, which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1T ( = DSM 23983T = LMG 26292T).

  • Helicobacter heilmannii sp. nov., isolated from feline gastric mucosa.
    International journal of systematic and evolutionary microbiology, 2011
    Co-Authors: Annemieke Smet, Richard Ducatelle, Bram Flahou, Ilse Cleenwerck, Peter Vandamme, Katharina D'herde, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Three gram-negative, microaerophilic bacteria, strains ASB1(T), ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1(T), ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter Bizzozeronii, 'Candidatus Helicobacter heilmannii', Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1(T), ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1(T), ASB2 and ASB3 showed approximately 91 % similarity to those of 'Candidatus Helicobacter heilmannii'. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1(T), ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to 'Candidatus Helicobacter heilmannii', which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1(T) (=DSM 24751 (T) =LMG 26292(T)) [corrected].

  • Non-Helicobacter pylori Helicobacters detected in the stomach of humans comprise several naturally occurring Helicobacter species in animals.
    Fems Immunology and Medical Microbiology, 2009
    Co-Authors: Margo Baele, Koen Chiers, Richard Ducatelle, Bram Flahou, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Besides the well-known gastric pathogen Helicobacter pylori, other Helicobacter species with a spiral morphology have been detected in a minority of human patients who have undergone gastroscopy. The very fastidious nature of these non-Helicobacter pylori Helicobacters (NHPH) makes their in vitro isolation difficult. These organisms have been designated 'Helicobacter heilmannii'. However, sequencing of several genes detected in NHPH-infected tissues has shown that the 'H. heilmannii' group comprises at least five different Helicobacter species, all of them known to colonize the stomach of animals. Recent investigations have indicated that Helicobacter suis is the most prevalent NHPH species in human. This species has only recently been isolated in vitro from porcine stomach mucosa. Other NHPH that colonize the human stomach are Helicobacter felis, Helicobacter Bizzozeronii, Helicobacter salomonis and 'Candidatus Helicobacter heilmannii'. In numerous case reports of human gastric NHPH infections, no substantial information is available about the species status of the infecting strain, making it difficult to link the species with certain pathologies. This review aims to clarify the complex nomenclature of NHPH species associated with human gastric disease and their possible animal origin. It is proposed to use the term 'gastric NHPH' to designate gastric spirals that are morphologically different from H. pylori when no identification is available at the species level. Species designations should be reserved for those situations in which the species is defined.

  • Isolation and characterization of Helicobacter suis sp. nov. from pig stomachs.
    International Journal of Systematic and Evolutionary Microbiology, 2008
    Co-Authors: Margo Baele, Ann Hellemans, Liesbeth Ceelen, J Mast, Koen Chiers, Annemie Decostere, Richard Ducatelle, Peter Vandamme, Freddy Haesebrouck
    Abstract:

    A new cultivation method was successfully applied for the in vitro isolation of a hitherto uncultured spiral Helicobacter species associated with ulceration of the non-glandular stomach and gastritis in pigs and formerly described as 'Candidatus Helicobacter suis'. Three isolates, HS1(T), HS2 and HS3, were subcultured from the stomach mucosa of three pigs after slaughter and were analysed using a polyphasic taxonomic approach. The novel isolates grew on biphasic culture plates or very moist agar bases in microaerobic conditions and exhibited urease, oxidase and catalase activities. Sequencing of the 16S rRNA gene, the 23S rRNA gene, the partial hsp60 gene and partial ureAB genes confirmed that the strains present in the gastric mucosa of pigs constituted a separate taxon, corresponding to 'Helicobacter heilmannii' type 1 strains as detected in the gastric mucosa of humans and other primates. For all genes sequenced, the highest sequence similarities were obtained with Helicobacter felis, Helicobacter Bizzozeronii and Helicobacter salomonis, Helicobacter species isolated from the gastric mucosa of dogs and cats, which have also been detected in the human gastric mucosa and which are commonly referred to as 'Helicobacter heilmannii' type 2. SDS-PAGE of whole-cell proteins of strains HS1(T), HS2 and HS3 differentiated them from other Helicobacter species of gastric origin. The results of the polyphasic taxonomic analysis confirmed that the novel isolates constitute a novel taxon corresponding to 'Helicobacter heilmannii' type 1 strains from humans and to 'Candidatus H. suis' from pigs. The name Helicobacter suis sp. nov. is proposed for the novel isolates with the type strain HS1(T) (=LMG 23995(T) =DSM 19735(T)).

Mirko Rossi - One of the best experts on this subject based on the ideXlab platform.

  • ML: Genome sequence of Helicobacter Bizzozeronii strain CIII-1, an isolate from human gastric mucosa
    2016
    Co-Authors: Thomas Schott, Mirko Rossi
    Abstract:

    The canine-adapted Helicobacter Bizzozeronii is the only nonpylori Helicobacter species isolated from human gastric biopsy tissue. Here we present the genome sequence of strain CIII-1, isolated from a 45-year-old female patient with severe gastric symptoms. This is the first genome sequence of nonpylori gastric Helicobacter isolated from human gastritis. Helicobacter pylori has been established as the primary cause of gastritis and peptic ulceration in humans and has been recognized as a major risk factor for mucosa-associated lym-phoid-tissue lymphoma and adenocarcinoma (3). However, in gastric biopsy tissues of a minority of patients (0.17 to 2.3%) with upper gastrointestinal symptoms, long, tightly coiled spiral bacteria, ascribed to nonpylori Helicobacter spp., can be ob-served (2). Among the five nonpylori gastric Helicobacter spe-cies reported to be associated with human infections (5), only Helicobacter Bizzozeronii has been successfully cultivated from gastric biopsy tissues of human patients (7, 8). Humans poten-tially acquire the infections as a consequence of direct contact with dogs and cats (10), which are normally colonized by H. Bizzozeronii (6). However, although virtually all cats and dogs carry this Helicobacter species, its pathogenic significance in these animals remains unknown (5). Here we present the ge-nome sequence of the Finnish human H. Bizzozeronii strain CIII-1, isolated in March 2008 from corpus biopsy tissue of a 45-year-old female patient with severe gastric symptoms (8). To our knowledge, this is the first genome sequence of non-pylori gastric Helicobacter isolated from humans. The draft genome sequence of H. Bizzozeronii CIII-1 was determined using a combination of 454 Titanium (43 ge-nome coverage, 8-kb mate pair library; performed by LG

  • Chondroitinase AC: A host-associated genetic feature of Helicobacter Bizzozeronii
    Veterinary microbiology, 2016
    Co-Authors: Ramesh Babu Namburi, Olivier Berteau, Dorothe Spillmann, Mirko Rossi
    Abstract:

    Investigating mechanisms involved in host adaptation is crucial to understand pathogen evolution. Helicobacter species appear to have a host species-specific tropism, coevolving with their natural hosts, and to develop several strategies allowing the colonization of the stomach throughout lifetime of their hosts. However, little is known about genetic features associated with the adaptation to a specific animal host. In this study we discovered a polysaccharide lyase that is expressed by the canine-associated species H. Bizzozeronii and acts as chondroitinase AC-type lyase of broad specificity. Except for its low pH-optimum between pH 4.0 and pH 5.5, the properties of the H. Bizzozeronii chondroitin lyase AC resemble the ones from Arthrobacter aurescens. However, homologues of this gene have been detected only in Helicobacter species colonizing the canine and feline gastric mucosa. Since a unique feature of the canine stomach is the secretion of chondroitin-4-sulphate in the gastric juice of the fundus mucosa by chief cells, the expression of chondroitinase AC by H. Bizzozeronii is likely the consequence of adaptation of this bacterium to its host and a potential link to gastric disorders in dogs.

  • Sialylation of Helicobacter Bizzozeronii lipopolysaccharides modulates Toll-like receptor (TLR) 2 mediated response
    Veterinary Research, 2015
    Co-Authors: Pradeep Kumar Kondadi, Marja-liisa Hänninen, Joana Revez, Mirko Rossi
    Abstract:

    Sialic acid in lipopolysaccharides (LPS) of mucosal pathogens is known to be an important virulence factor. Few strains of Helicobacter pylori express sialyl-Lewis-X and we have reported that human and canine Helicobacter Bizzozeronii strains express sialyl-lactoseamine in their LPS. However, the role of sialyation of Helicobacter LPS in the interaction with the host cells is still unknown. In this study H. Bizzozeronii LPS is shown to activate the TLR2 in a dose and strain dependent manner in the in vitro HEK-293 cells model expressing TLR2, but not the cells expressing TLR4. These results indicate that TLR2 is the specific receptor for H. bizzozzeronii LPS, as previously described for H. pylori. To further explore the role of sialylation of H. Bizzozeronii LPS on TLR2 response, H. Bizzozeronii Δhbs2 mutant strains deficient in sialyltransferase activity were constructed by homologous recombination. LPS from H. Bizzozeronii Δhbs2 strains enhanced the NF-ĸB induction via TLR2 compared to the respective wild types, leading to the conclusion that the sialylation of H. Bizzozeronii LPS in wild-type strains may modulate host immune response.

  • Sialylation of Helicobacter Bizzozeronii lipopolysaccharides modulates Toll-like receptor (TLR) 2 mediated response
    Veterinary Research, 2015
    Co-Authors: Pradeep Kumar Kondadi, Marja-liisa Hänninen, Joana Revez, Mirko Rossi
    Abstract:

    Sialic acid in lipopolysaccharides (LPS) of mucosal pathogens is known to be an important virulence factor. Few strains of Helicobacter pylori express sialyl-Lewis-X and we have reported that human and canine Helicobacter Bizzozeronii strains express sialyl-lactoseamine in their LPS. However, the role of sialyation of Helicobacter LPS in the interaction with the host cells is still unknown. In this study H. Bizzozeronii LPS is shown to activate the TLR2 in a dose and strain dependent manner in the in vitro HEK-293 cells model expressing TLR2, but not the cells expressing TLR4. These results indicate that TLR2 is the specific receptor for H. bizzozzeronii LPS, as previously described for H. pylori. To further explore the role of sialylation of H. Bizzozeronii LPS on TLR2 response, H. Bizzozeronii Δhbs2 mutant strains deficient in sialyltransferase activity were constructed by homologous recombination. LPS from H. Bizzozeronii Δhbs2 strains enhanced the NF-ĸB induction via TLR2 compared to the respective wild types, leading to the conclusion that the sialylation of H. Bizzozeronii LPS in wild-type strains may modulate host immune response.

  • Contingency nature of Helicobacter Bizzozeronii oxygen-insensitive NAD(P)H-nitroreductase (HBZC1_00960) and its role in metronidazole resistance
    Veterinary Research, 2013
    Co-Authors: Pradeep Kumar Kondadi, Marja-liisa Hänninen, Joana Revez, Claudia Pacini, Mirko Rossi
    Abstract:

    Genomic analysis of a metronidazole resistant H. Bizzozeronii strain revealed a frame length extension of the oxygen-insensitive NAD(P)H-nitroreductase HBZC1_00960 (RdxA), associated with the disruption of the C-terminal cysteine-containing conserved region (IACLXALGK). This was the result of the extension (from C_8 to C_9) of a simple sequence cytosine repeat (SSCR) located in the 3’ of the gene. A 3' SSCR is also present in the rdxA homolog of H. heilmannii sensu stricto, but not in H. pylori . We showed that in the majority of in vitro spontaneous H. Bizzozeronii metronidazole resistant mutants, the extension of the 3′ SSCR of rdxA was the only mutation observed. In addition, we observed that H. Bizzozeronii Δ rdxA mutant strain showed the same MIC value of metronidazole observed in the spontaneous mutants. These data indicate that loss of function mutations in rdxA and in particular the disruption of the conserved region IACLXALGK is associated with reduced susceptibility to metronidazole in H. Bizzozeronii . Slipped-strand mispairing of the SSCR located in the 3′ of the H. Bizzozeronii rdxA appears to be the main mechanism. We also observed that H. Bizzozeronii acquires resistance to metronidazole at high mutation rate, and that serial passages in vitro without selection induced an increased level of susceptibility. In conclusion, contrary to what was previously described in H. pylori , the H. Bizzozeronii rdxA appears to be a contingency gene which undergoes phase variation. The contingency nature of rdxA should be carefully considered when metronidazole is used in the treatment of H. heilmannii -associated gastritis.

Richard Ducatelle - One of the best experts on this subject based on the ideXlab platform.

  • Helicobacter heilmannii sp nov isolated from feline gastric mucosa
    International Journal of Systematic and Evolutionary Microbiology, 2012
    Co-Authors: Annemieke Smet, Richard Ducatelle, Katharina Dherde, Bram Flahou, Ilse Cleenwerck, Peter Vandamme, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Three Gram-negative, microaerophilic bacteria, strains ASB1T, ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1T, ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter Bizzozeronii, ‘Candidatus Helicobacter heilmannii’, Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1T, ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1T, ASB2 and ASB3 showed approximately 91 % similarity to those of ‘Candidatus Helicobacter heilmannii’. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1T, ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to ‘Candidatus Helicobacter heilmannii’, which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1T ( = DSM 23983T = LMG 26292T).

  • Helicobacter heilmannii sp. nov., isolated from feline gastric mucosa.
    International journal of systematic and evolutionary microbiology, 2011
    Co-Authors: Annemieke Smet, Richard Ducatelle, Bram Flahou, Ilse Cleenwerck, Peter Vandamme, Katharina D'herde, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Three gram-negative, microaerophilic bacteria, strains ASB1(T), ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1(T), ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter Bizzozeronii, 'Candidatus Helicobacter heilmannii', Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1(T), ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1(T), ASB2 and ASB3 showed approximately 91 % similarity to those of 'Candidatus Helicobacter heilmannii'. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1(T), ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to 'Candidatus Helicobacter heilmannii', which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1(T) (=DSM 24751 (T) =LMG 26292(T)) [corrected].

  • Non-Helicobacter pylori Helicobacters detected in the stomach of humans comprise several naturally occurring Helicobacter species in animals.
    Fems Immunology and Medical Microbiology, 2009
    Co-Authors: Margo Baele, Koen Chiers, Richard Ducatelle, Bram Flahou, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Besides the well-known gastric pathogen Helicobacter pylori, other Helicobacter species with a spiral morphology have been detected in a minority of human patients who have undergone gastroscopy. The very fastidious nature of these non-Helicobacter pylori Helicobacters (NHPH) makes their in vitro isolation difficult. These organisms have been designated 'Helicobacter heilmannii'. However, sequencing of several genes detected in NHPH-infected tissues has shown that the 'H. heilmannii' group comprises at least five different Helicobacter species, all of them known to colonize the stomach of animals. Recent investigations have indicated that Helicobacter suis is the most prevalent NHPH species in human. This species has only recently been isolated in vitro from porcine stomach mucosa. Other NHPH that colonize the human stomach are Helicobacter felis, Helicobacter Bizzozeronii, Helicobacter salomonis and 'Candidatus Helicobacter heilmannii'. In numerous case reports of human gastric NHPH infections, no substantial information is available about the species status of the infecting strain, making it difficult to link the species with certain pathologies. This review aims to clarify the complex nomenclature of NHPH species associated with human gastric disease and their possible animal origin. It is proposed to use the term 'gastric NHPH' to designate gastric spirals that are morphologically different from H. pylori when no identification is available at the species level. Species designations should be reserved for those situations in which the species is defined.

  • Isolation and characterization of Helicobacter suis sp. nov. from pig stomachs.
    International Journal of Systematic and Evolutionary Microbiology, 2008
    Co-Authors: Margo Baele, Ann Hellemans, Liesbeth Ceelen, J Mast, Koen Chiers, Annemie Decostere, Richard Ducatelle, Peter Vandamme, Freddy Haesebrouck
    Abstract:

    A new cultivation method was successfully applied for the in vitro isolation of a hitherto uncultured spiral Helicobacter species associated with ulceration of the non-glandular stomach and gastritis in pigs and formerly described as 'Candidatus Helicobacter suis'. Three isolates, HS1(T), HS2 and HS3, were subcultured from the stomach mucosa of three pigs after slaughter and were analysed using a polyphasic taxonomic approach. The novel isolates grew on biphasic culture plates or very moist agar bases in microaerobic conditions and exhibited urease, oxidase and catalase activities. Sequencing of the 16S rRNA gene, the 23S rRNA gene, the partial hsp60 gene and partial ureAB genes confirmed that the strains present in the gastric mucosa of pigs constituted a separate taxon, corresponding to 'Helicobacter heilmannii' type 1 strains as detected in the gastric mucosa of humans and other primates. For all genes sequenced, the highest sequence similarities were obtained with Helicobacter felis, Helicobacter Bizzozeronii and Helicobacter salomonis, Helicobacter species isolated from the gastric mucosa of dogs and cats, which have also been detected in the human gastric mucosa and which are commonly referred to as 'Helicobacter heilmannii' type 2. SDS-PAGE of whole-cell proteins of strains HS1(T), HS2 and HS3 differentiated them from other Helicobacter species of gastric origin. The results of the polyphasic taxonomic analysis confirmed that the novel isolates constitute a novel taxon corresponding to 'Helicobacter heilmannii' type 1 strains from humans and to 'Candidatus H. suis' from pigs. The name Helicobacter suis sp. nov. is proposed for the novel isolates with the type strain HS1(T) (=LMG 23995(T) =DSM 19735(T)).

  • Helicobacter baculiformis sp. nov., isolated from feline stomach mucosa
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY, 2008
    Co-Authors: Margo Baele, J Mast, Annemie Decostere, Richard Ducatelle, Peter Vandamme, K. Van Den Bulck, Igor Gruntar, J. Mehle, Freddy Haesebrouck
    Abstract:

    A Gram-negative, microaerophilic slender rod, measuring approximately 10 μm long and approximately 1 μm wide, isolated from the gastric mucosa of a cat and designated strain M50T, was subjected to a polyphasic taxonomic study. Despite its apparent lack of helical coils, the organism showed a corkscrew-like motion by means of multiple sheathed flagella located at both ends of the cell and by a periplasmic fibril coiled around the body. Strain M50T grew preferably on biphasic culture plates or on very moist agar. Coccoid forms predominated in cultures older than 4 days as well as in growth obtained on dry agar plates. The strain grew at 37 °C, but not at 25 or 42 °C and exhibited urease, oxidase and catalase activities. On the basis of 16S rRNA gene sequence analysis, the novel isolate was identified as a member of the genus Helicobacter and showed about 98 to 99 % sequence similarity to Helicobacter felis, Helicobacter Bizzozeronii, Helicobacter salomonis, Helicobacter cynogastricus and ‘Candidatus Helicobacter heilmannii’, five highly related species previously detected in the feline or canine gastric mucosa. Protein profiling of strain M50T using SDS-PAGE revealed a pattern different from those of other Helicobacter species of mammalian gastric origin. Additionally, the urease and HSP60 gene sequences of strain M50T were different from those of H. felis, H. Bizzozeronii, H. salomonis, H. cynogastricus and ‘Ca. H. heilmannii’. It is thus proposed that strain M50T (=LMG 23839T=CCUG 53816T) represents a novel species within this genus, for which the name Helicobacter baculiformis sp. nov. is proposed.

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  • Helicobacter heilmannii sp nov isolated from feline gastric mucosa
    International Journal of Systematic and Evolutionary Microbiology, 2012
    Co-Authors: Annemieke Smet, Richard Ducatelle, Katharina Dherde, Bram Flahou, Ilse Cleenwerck, Peter Vandamme, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Three Gram-negative, microaerophilic bacteria, strains ASB1T, ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1T, ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter Bizzozeronii, ‘Candidatus Helicobacter heilmannii’, Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1T, ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1T, ASB2 and ASB3 showed approximately 91 % similarity to those of ‘Candidatus Helicobacter heilmannii’. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1T, ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to ‘Candidatus Helicobacter heilmannii’, which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1T ( = DSM 23983T = LMG 26292T).

  • Helicobacter heilmannii sp. nov., isolated from feline gastric mucosa.
    International journal of systematic and evolutionary microbiology, 2011
    Co-Authors: Annemieke Smet, Richard Ducatelle, Bram Flahou, Ilse Cleenwerck, Peter Vandamme, Katharina D'herde, Frank Pasmans, Freddy Haesebrouck
    Abstract:

    Three gram-negative, microaerophilic bacteria, strains ASB1(T), ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1(T), ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter Bizzozeronii, 'Candidatus Helicobacter heilmannii', Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1(T), ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1(T), ASB2 and ASB3 showed approximately 91 % similarity to those of 'Candidatus Helicobacter heilmannii'. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1(T), ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to 'Candidatus Helicobacter heilmannii', which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1(T) (=DSM 24751 (T) =LMG 26292(T)) [corrected].

  • Isolation and characterization of Helicobacter suis sp. nov. from pig stomachs.
    International Journal of Systematic and Evolutionary Microbiology, 2008
    Co-Authors: Margo Baele, Ann Hellemans, Liesbeth Ceelen, J Mast, Koen Chiers, Annemie Decostere, Richard Ducatelle, Peter Vandamme, Freddy Haesebrouck
    Abstract:

    A new cultivation method was successfully applied for the in vitro isolation of a hitherto uncultured spiral Helicobacter species associated with ulceration of the non-glandular stomach and gastritis in pigs and formerly described as 'Candidatus Helicobacter suis'. Three isolates, HS1(T), HS2 and HS3, were subcultured from the stomach mucosa of three pigs after slaughter and were analysed using a polyphasic taxonomic approach. The novel isolates grew on biphasic culture plates or very moist agar bases in microaerobic conditions and exhibited urease, oxidase and catalase activities. Sequencing of the 16S rRNA gene, the 23S rRNA gene, the partial hsp60 gene and partial ureAB genes confirmed that the strains present in the gastric mucosa of pigs constituted a separate taxon, corresponding to 'Helicobacter heilmannii' type 1 strains as detected in the gastric mucosa of humans and other primates. For all genes sequenced, the highest sequence similarities were obtained with Helicobacter felis, Helicobacter Bizzozeronii and Helicobacter salomonis, Helicobacter species isolated from the gastric mucosa of dogs and cats, which have also been detected in the human gastric mucosa and which are commonly referred to as 'Helicobacter heilmannii' type 2. SDS-PAGE of whole-cell proteins of strains HS1(T), HS2 and HS3 differentiated them from other Helicobacter species of gastric origin. The results of the polyphasic taxonomic analysis confirmed that the novel isolates constitute a novel taxon corresponding to 'Helicobacter heilmannii' type 1 strains from humans and to 'Candidatus H. suis' from pigs. The name Helicobacter suis sp. nov. is proposed for the novel isolates with the type strain HS1(T) (=LMG 23995(T) =DSM 19735(T)).

  • Helicobacter baculiformis sp. nov., isolated from feline stomach mucosa
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY, 2008
    Co-Authors: Margo Baele, J Mast, Annemie Decostere, Richard Ducatelle, Peter Vandamme, K. Van Den Bulck, Igor Gruntar, J. Mehle, Freddy Haesebrouck
    Abstract:

    A Gram-negative, microaerophilic slender rod, measuring approximately 10 μm long and approximately 1 μm wide, isolated from the gastric mucosa of a cat and designated strain M50T, was subjected to a polyphasic taxonomic study. Despite its apparent lack of helical coils, the organism showed a corkscrew-like motion by means of multiple sheathed flagella located at both ends of the cell and by a periplasmic fibril coiled around the body. Strain M50T grew preferably on biphasic culture plates or on very moist agar. Coccoid forms predominated in cultures older than 4 days as well as in growth obtained on dry agar plates. The strain grew at 37 °C, but not at 25 or 42 °C and exhibited urease, oxidase and catalase activities. On the basis of 16S rRNA gene sequence analysis, the novel isolate was identified as a member of the genus Helicobacter and showed about 98 to 99 % sequence similarity to Helicobacter felis, Helicobacter Bizzozeronii, Helicobacter salomonis, Helicobacter cynogastricus and ‘Candidatus Helicobacter heilmannii’, five highly related species previously detected in the feline or canine gastric mucosa. Protein profiling of strain M50T using SDS-PAGE revealed a pattern different from those of other Helicobacter species of mammalian gastric origin. Additionally, the urease and HSP60 gene sequences of strain M50T were different from those of H. felis, H. Bizzozeronii, H. salomonis, H. cynogastricus and ‘Ca. H. heilmannii’. It is thus proposed that strain M50T (=LMG 23839T=CCUG 53816T) represents a novel species within this genus, for which the name Helicobacter baculiformis sp. nov. is proposed.

  • Helicobacter cynogastricus sp. nov., isolated from the canine gastric mucosa
    International Journal of Systematic and Evolutionary Microbiology, 2006
    Co-Authors: K. Van Den Bulck, J Mast, Margo Baele, Annemie Decostere, Richard Ducatelle, Peter Vandamme, Freddy Haesebrouck
    Abstract:

    A Gram-negative, microaerophilic helical rod, isolated from the gastric mucosa of a dog and designated strain JKM4T, was subjected to a polyphasic taxonomic study. The tightly coiled organism, measuring 10–18 μm long and up to 1 μm wide, was motile by means of multiple sheathed flagella located at both ends of the cell and by a periplasmic fibril running along the external side of the helix. Strain JKM4T grew preferably on biphasic culture plates or on very moist agar. Coccoid forms predominated in cultures older than 4 days as well as in growth obtained on dry agar plates. The strain grew at 30 and 37 °C, but not at 25 or 42 °C and exhibited urease, oxidase and catalase activities. On the basis of 16S rRNA gene sequence analysis, the novel isolate was identified as a member of the genus Helicobacter and showed > 97 % similarity to Helicobacter felis, Helicobacter Bizzozeronii and Helicobacter salomonis, three species previously isolated from the canine gastric mucosa. Protein profiling of strain JKM4T using SDS-PAGE revealed a pattern different from those of other Helicobacter species of mammalian gastric origin and from Helicobacter canis. Additionally, the urease gene sequence of strain JKM4T was different from those of urease genes of H. felis, H. Bizzozeronii, H. salomonis and ‘Candidatus Helicobacter heilmannii’. It is thus proposed that strain JKM4T (=LMG 23188T) represents a novel species within this genus, Helicobacter cynogastricus sp. nov.