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Peter Vandamme - One of the best experts on this subject based on the ideXlab platform.

  • identification and epidemiological typing of Campylobacter Hyointestinalis subspecies by phenotypic and genotypic methods and description of novel subgroups
    Systematic and Applied Microbiology, 1997
    Co-Authors: Peter Vandamme
    Abstract:

    Summary Twenty-eight type, reference, and field strains classified as, or closely resembling Campylobacter Hyointestinalis , were characterised by phenotypic tests, whole-cell protein-, and macrorestriction profiling. The phenotypic, and protein data, were objectively evaluated by numerical analyses. Each of the methods employed were able to differentiate isolates classified as C. Hyointestinalis subsp. Hyointestinalis and C. Hyointestinalis subsp. lawsonii . However, two strains of the latter proved to be phenotypically atypical. These strains appeared to be closely related and may represent an atypical lineage of this taxon. Two novel, distinct groups of C. Hyointestinalis -like bacteria, originally isolated from the cloacae of Canada geese and human diarrhoeic stools, were also identified by each of the methods used. This appears to be the first report confirming the presence of C. Hyointestinalis -like strains from birds and may be significant since the carriage of Campylobacters in other avian species is a known risk factor in the dissemination of enteric disease. This study shows that strains resembling C. Hyointestinalis should be characterised more extensively in order to accurately establish their identity and thus provide important information regarding the prevalence, importance, and epidemiology of the defined subspecies, and the novel groups described here. Simultaneous identification and subtyping of each taxon can be effected by protein- and/or macrorestriction profiling.

  • Campylobacter Hyointestinalis subsp lawsonii subsp nov isolated from the porcine stomach and an emended description of Campylobacter Hyointestinalis
    International Journal of Systematic and Evolutionary Microbiology, 1995
    Co-Authors: Buchardt Bloch, Bart Hoste, Barry Holmes, Peter Vandamme
    Abstract:

    The taxonomic relationships of seven isolates obtained from porcine stomachs (the “CHY” group), which resembled (but were distinct from) the type strain and other reference strains of Campylobacter Hyointestinalis, were examined by using phenotypic and genomic methods. The phenotypic characteristics and ultrastructure of the new organisms were characteristic of Campylobacter species, although they could be distinguished from all previously described taxa. A numerical analysis of 38 phenotypic characters revealed that the new isolates formed a distinct group at a similarity level of 90.1% and could be clearly distinguished from reference strains representing 20 related taxa, principally species and subspecies belonging to the genera Campylobacter, Arcobacter, and Helicobacter. DNA-DNA hybridization studies revealed that the porcine stomach strains were genomically homogeneous (levels of relatedness, 84 to 90%), although the levels of DNA homology with type and reference strains of C. Hyointestinalis were relatively high (56 to 71%). Differences in the DNA base compositions of the CHY group and C. Hyointestinalis strains were also observed. Our data indicate that the new porcine isolates should be considered members of a subspecies of C. Hyointestinalis. for which we propose the name Campylobacter Hyointestinalis subsp. lawsonii subsp. nov. The type strain is strain CHY 5 (= LMG 14432 = NCTC 12901 = CCUG 34538). The description of C. Hyointestinalis is emended accordingly, and a description of Campylobacter Hyointestinalis subsp. Hyointestinalis subsp. nov. is given.

  • revision of Campylobacter helicobacter and wolinella taxonomy emendation of generic descriptions and proposal of arcobacter gen nov
    International Journal of Systematic and Evolutionary Microbiology, 1991
    Co-Authors: Peter Vandamme, Rudi Rossau, Bart Hoste, Enevold Falsen, Patrick Segers, R Tytgat
    Abstract:

    Hybridization experiments were carried out between DNAs from more than 70 strains of Campylobacter spp. and related taxa and either 3H-labeled 23S rRNAs from reference strains belonging to Campylobacter fetus, Campylobacter concisus, Campylobacter sputorum, Campylobacter coli, and Campylobacter nitrofigilis, an unnamed Campylobacter sp. strain, and a Wolinella succinogenes strain or 3H- or 14C-labeled 23S rRNAs from 13 gram-negative reference strains. An immunotyping analysis of 130 antigens versus 34 antisera of Campylobacters and related taxa was also performed. We found that all of the named Campylobacters and related taxa belong to the same phylogenetic group, which we name rRNA superfamily VI and which is far removed from the gram-negative bacteria allocated to the five rRNA superfamilies sensu De Ley. There is a high degree of heterogeneity within this rRNA superfamily. Organisms belonging to rRNA superfamily VI should be reclassified in several genera. We propose that the emended genus Campylobacter should be limited to Campylobacter fetus, Campylobacter Hyointestinalis, Campylobacter concisus, Campylobacter mucosalis, Campylobacter sputorum, Campylobacter jejuni, Campylobacter coli, Campylobacter Iari, and “Campylobacter upsaliensis.” Wolinella curva and Wolinella recta are transferred to the genus Campylobacter as Campylobacter curvus comb. nov. and Campylobacter rectus comb. nov., respectively. Bacteroides gracilis and Bacteroides ureolyticus are generically misnamed and are closely related to the genus Campylobacter. Campylobacter nitrofigilis, Campylobacter cryaerophila, and an unnamed Campylobacter sp. strain constitute a new genus, for which the name Arcobacter is proposed; this genus contains two species, Arcobacter nitrofigilis comb. nov. (type species) and Arcobacter cryaerophilus comb. nov. Wolinella succinogenes so far is the only species of the genus Wolinella. The genus Helicobacter is also emended; Campylobacter cinaedi and Campylobacter fennelliae are included in this genus as Helicobacter cinaedi comb. nov. and Helicobacter fennelliae comb. nov., respectively. The genus “Flexispira,” with “Flexispira rappini” as the only species, is closely related to the genus Helicobacter. The free-living, sulfur-reducing Campylobacters do not belong to any of these genera; they probably constitute a distinct genus within rRNA superfamily VI.

Gregorio Iraola - One of the best experts on this subject based on the ideXlab platform.

  • pangenome analysis reveals genetic isolation in Campylobacter Hyointestinalis subspecies adapted to different mammalian hosts
    Scientific Reports, 2021
    Co-Authors: Daniela Costa, Simon Levesque, Nitin Kumar, Pablo Fresia, Ignacio Ferres, Trevor D Lawley, Gregorio Iraola
    Abstract:

    Campylobacter Hyointestinalis is an emerging pathogen currently divided in two subspecies: C. Hyointestinalis subsp. lawsonii which is predominantly recovered from pigs, and C. Hyointestinalis subsp. Hyointestinalis which can be found in a much wider range of mammalian hosts. Despite C. Hyointestinalis being reported as an emerging pathogen, its evolutionary and host-associated diversification patterns are still vastly unexplored. For this reason, we generated whole-genome sequences of 13 C. Hyointestinalis subsp. Hyointestinalis strains and performed a comprehensive comparative analysis including publicly available C. Hyointestinalis subsp. Hyointestinalis and C. Hyointestinalis subsp. lawsonii genomes, to gain insight into the genomic variation of these differentially-adapted subspecies. Both subspecies are distinct phylogenetic lineages which present an apparent barrier to homologous recombination, suggesting genetic isolation. This is further supported by accessory gene patterns that recapitulate the core genome phylogeny. Additionally, C. Hyointestinalis subsp. Hyointestinalis presents a bigger and more diverse accessory genome, which probably reflects its capacity to colonize different mammalian hosts unlike C. Hyointestinalis subsp. lawsonii that is presumably host-restricted. This greater plasticity in the accessory genome of C. Hyointestinalis subsp. Hyointestinalis correlates to a higher incidence of genome-wide recombination events, that may be the underlying mechanism driving its diversification. Concordantly, both subspecies present distinct patterns of gene families involved in genome plasticity and DNA repair like CRISPR-associated proteins and restriction-modification systems. Together, our results provide an overview of the genetic mechanisms shaping the genomes of C. Hyointestinalis subspecies, contributing to understand the biology of Campylobacter species that are increasingly recognized as emerging pathogens.

  • pangenome analysis reveals genetic isolation in Campylobacter Hyointestinalis subspecies adapted to different mammalian hosts
    bioRxiv, 2019
    Co-Authors: Daniela Costa, Simon Levesque, Nitin Kumar, Pablo Fresia, Ignacio Ferres, Trevor D Lawley, Gregorio Iraola
    Abstract:

    Campylobacter Hyointestinalis is an emerging pathogen currently divided in two subspecies: C. Hyointestinalis subsp. lawsonii which is restricted to pigs, and C. Hyointestinalis subsp. Hyointestinalis which can be found in a much wider range of mammalian hosts. Despite C. Hyointestinalis has been reported as an emerging pathogen, its evolutionary and host-associated diversification patterns are still vastly unexplored. For this reason, we whole-genome sequenced 13 C. Hyointestinalis subsp. Hyointestinalis strains and performed a comprehensive comparative analysis including publicly available genomes of C. Hyointestinalis subsp. Hyointestinalis and C. Hyointestinalis subsp. lawsonii to gain insight into the genomic variation of these differentially-adapted subspecies. Both subspecies are distinct phylogenetic lineages which present a barrier to homologous recombination, suggesting genetic isolation. This is further supported by accessory gene patterns that recapitulate the core genome phylogeny. Additionally, C. Hyointestinalis subsp. Hyointestinalis presents a bigger and more diverse accessory genome, which probably reflects its capacity to colonize different mammalian hosts unlike C. Hyointestinalis subsp. lawsonii that is host-restricted. This greater plasticity in the accessory genome of C. Hyointestinalis subsp. Hyointestinalis correlates to a higher incidence of genome-wide recombination events, that may be the underlying mechanism driving its diversification. Concordantly, both subspecies present distinct patterns of gene families involved in genome plasticity and DNA repair like CRISPR-associated proteins and restriction-modification systems. Together, our results provide an overview of the genetic mechanisms shaping the genomes of C. Hyointestinalis subspecies, contributing to understand the biology of Campylobacter species that are increasingly found as emerging pathogens.

N P French - One of the best experts on this subject based on the ideXlab platform.

  • updating the genomic taxonomy and epidemiology of Campylobacter Hyointestinalis
    Scientific Reports, 2018
    Co-Authors: David A Wilkinson, Andrew J Odonnell, Rukhshana N Akhter, Ahmed Fayaz, Hamish J Mack, Lynn Rogers, Patrick J Biggs, N P French, Anne C Midwinter
    Abstract:

    Campylobacter Hyointestinalis is a member of an emerging group of zoonotic Campylobacter spp. that are increasingly identified in both gastric and non-gastric disease in humans. Here, we discovered C. Hyointestinalis in three separate classes of New Zealand ruminant livestock; cattle, sheep and deer. To investigate the relevance of these findings we performed a systematic literature review on global C. Hyointestinalis epidemiology and used comparative genomics to better understand and classify members of the species. We found that C. Hyointestinalis subspecies Hyointestinalis has an open pangenome, with accessory gene contents involved in many essential processes such as metabolism, virulence and defence. We observed that horizontal gene transfer is likely to have played an overwhelming role in species diversification, favouring a public-goods-like mechanism of gene 'acquisition and resampling' over a tree-of-life-like vertical inheritance model of evolution. As a result, simplistic gene-based inferences of taxonomy by similarity are likely to be misleading. Such genomic plasticity will also mean that local evolutionary histories likely influence key species characteristics, such as host-association and virulence. This may help explain geographical differences in reported C. Hyointestinalis epidemiology and limits what characteristics may be generalised, requiring further genomic studies of C. Hyointestinalis in areas where it causes disease.

  • 2005) Prevalence and genetic diversity of Campylobacter spp. in environmental water samples from a 100-square-kilometer predominantly dairy farming
    2008
    Co-Authors: R. Kemp, J. Turner, E. J. Wright, N P French
    Abstract:

    Water samples were taken systematically from a 100-km 2 area of mainly dairy farmland in northwestern England and examined for Campylobacter spp. Pulsed-field gel electrophoresis–restriction fragment length polymorphism (PFGE-RFLP) and flaA strain typing of Campylobacter jejuni and Campylobacter coli isolates were done. Data on the water source and the adjacent environment were recorded and examined as explanatory variables. Campylobacter spp. were isolated from 40.5 % (n � 119) of the water samples tested. C. jejuni was isolated from 14.3%, C. coli was isolated from 18.5%, and Campylobacter lari was isolated from 4.2 % of the samples. Campylobacter Hyointestinalis was not isolated from any water source. The difference in prevalence between water types (trough, running, and standing) was significant (P � 0.001). C. jejuni was the species most commonly isolated from trough-water and running-water sources, while C. coli was the most frequently isolated from standing water (P < 0.001). No association was found between the presence of Escherichia coli and that of Campylobacter spp. The final multivariable logistic regression model for Campylobacter spp. included the following variables: water source, soil type, aspect, and amount of cattle fecal material in the environment (fecal pat count). Strain typing demonstrated a diverse population of C. jejuni and the presence of a common C. coli flaA type that was widely distributed throughout the area. Most of the isolates within the common flaA type were discriminated by PFGE-RFLP. These findings suggest a possible role for environmental water in th

  • prevalence and genetic diversity of Campylobacter spp in environmental water samples from a 100 square kilometer predominantly dairy farming area
    Applied and Environmental Microbiology, 2005
    Co-Authors: R. Kemp, J. Turner, E. J. Wright, A J H Leatherbarrow, Nicola J Williams, C A Hart, Helen E Clough, N P French
    Abstract:

    Water samples were taken systematically from a 100-km2 area of mainly dairy farmland in northwestern England and examined for Campylobacter spp. Pulsed-field gel electrophoresis-restriction fragment length polymorphism (PFGE-RFLP) and flaA strain typing of Campylobacter jejuni and Campylobacter coli isolates were done. Data on the water source and the adjacent environment were recorded and examined as explanatory variables. Campylobacter spp. were isolated from 40.5% (n = 119) of the water samples tested. C. jejuni was isolated from 14.3%, C. coli was isolated from 18.5%, and Campylobacter lari was isolated from 4.2% of the samples. Campylobacter Hyointestinalis was not isolated from any water source. The difference in prevalence between water types (trough, running, and standing) was significant (P = 0.001). C. jejuni was the species most commonly isolated from trough-water and running-water sources, while C. coli was the most frequently isolated from standing water (P < 0.001). No association was found between the presence of Escherichia coli and that of Campylobacter spp. The final multivariable logistic regression model for Campylobacter spp. included the following variables: water source, soil type, aspect, and amount of cattle fecal material in the environment (fecal pat count). Strain typing demonstrated a diverse population of C. jejuni and the presence of a common C. coli flaA type that was widely distributed throughout the area. Most of the isolates within the common flaA type were discriminated by PFGE-RFLP. These findings suggest a possible role for environmental water in the epidemiology of Campylobacter spp. in a farming environment.

Bruce J. Paster - One of the best experts on this subject based on the ideXlab platform.

  • Campylobacter hyoilei sp nov associated with porcine proliferative enteritis
    International Journal of Systematic and Evolutionary Microbiology, 1995
    Co-Authors: Malcolm R Alderton, Floyd E. Dewhirst, Victoria Korolik, Peter J Coloe, Bruce J. Paster
    Abstract:

    Campylobacter hyoilei sp. nov. is the name proposed for an organism formerly described as strain RMIT 32AT (T = type strain) and a group of similar bacteria isolated from intestinal lesions of pigs with proliferative enteritis. The phenotypic characteristics of these organisms indicated that they are closely related to each other and are not strains of other Campylobacter spp. commonly isolated from pigs. The results of probing of Cla I-, Eco RV-, or Bg/II-cleaved genomic DNAs from C. hyoilei strains with a radiolabeled DNA probe that distinguishes between Campylobacter jejuni and Campylobacter coli indicated that C. hyoilei and C. coli are closely related. However, the 16S rRNA sequence of the reference strain of C. hyoilei, RMIT 32AT, was four bases different from the 16S rRNA sequence of C. jejuni CCUG 11284T and five bases different from the 16S rRNA sequence of C. jejuni subsp. doylei CCUG 24567T, suggesting that C. hyoilei is more closely related to C. jejuni than to C. coli. Hybridization between DNA from C. hyoilei type strain RMIT 32A and DNAs from selected type and reference strains of other Campylobacter species and subspecies, including C. jejuni, C. jejuni subsp. doylei, C. coli, Campylobacter mucosalis, and Campylobacter Hyointestinalis, as well as the other C. hyoilei strains (the RMIT 32AT-like isolates), revealed that high levels of DNA hybridization (>70%) occurred only between the reference strain and other strains of C. hyoilei.

  • Helicobacter acinonyx sp. nov., isolated from cheetahs with gastritis.
    International journal of systematic bacteriology, 1993
    Co-Authors: Kathryn A. Eaton, Floyd E. Dewhirst, M. J. Radin, James G. Fox, Bruce J. Paster, Steven Krakowka, Douglas R. Morgan
    Abstract:

    Four strains of a novel Helicobacter species were isolated from the stomachs of cheetahs (Acinonyx jubilatus) with gastritis. These isolates were phenotypically similar to Helicobacter pylori. The isolates were gram-negative, spiral bacteria which grew under microaerophilic conditions at 37°C, but not at 25 or 42°C, and produced urease, catalase, oxidase, alkaline phosphatase, and gamma-glutamyl transpeptidase. The isolates did not ferment glucose, mannitol, inositol, sorbitol, rhamnose, sucrose, melibiose, amygdalin, or arabinose; hydrolyze hippurate or indoxyl acetate; or reduce nitrate. They did not produce H2S from triple sugar iron agar, and they did not grow in the presence of 1.0% glycine or 1.5% NaCI. They were resistant to nalidixic acid and sensitive to cephalothin and metronidazole. Cells were typically 0.3 by 2.0 μm and possessed tufts of two to five sheathed, monopolar flagella. The G+C content of strain 90-119 was 30 mol%. Cluster analysis of densitometry scans of polyacrylamide protein gels revealed more than 70% similarity of the cheetah isolates to H. pylori, less than 60% similarity to Helicobacter felis, and less than 50% similarity to Helicobacter mustelae. Complete 16S rRNA sequences were determined for two of the cheetah isolates. Phylogenetic analysis was performed by comparing the cheetah sequences to those of 19 reference strains, including H. pylori, H. felis (two strains), H. mustelae, Helicobacter muridarum, “Flexispira rappini,” Wolinella succinogenes, Campylobacter coli, Campylobacter concisus, Campylobacter curvus, Campylobacter fetus, Campylobacter Hyointestinalis, Campylobacter jejuni, Campylobacter lari, Campylobacter rectus, Campylobacter sputorum subsp. bubulus, a Campylobacter sp. (pigisolate), [Bacteroides] gracilis, and [Bacteroides] ureolyticus. The 16S rRNA sequences for 13 of the 19 reference species have not previously been reported. Phylogenetic analysis demonstrated that the cheetah isolates were most closely related to H. pylori (97.4% similarity), H. felis (96.1% similarity), and H. mustelae (93.4% similarity). On the basis of these findings, we propose that these isolates represents a novel species of Helicobacter, which we designate Helicobacter acinonyx. The type strain is 90-119 (CCUG 29263, ATCC 51101).

  • oligodeoxynucleotide probes for Campylobacter fetus and Campylobacter Hyointestinalis based on 16s rrna sequences
    Journal of Clinical Microbiology, 1991
    Co-Authors: Irene V Wesley, Floyd E. Dewhirst, R D Wesley, M Cardella, Bruce J. Paster
    Abstract:

    Deoxyoligonucleotide probes were constructed for the identification of Campylobacter fetus and Campylobacter Hyointestinalis based on 16S rRNA sequence data. Probes were targeted to hypervariable regions of 16S rRNA. Specificity of oligonucleotide probes was tested in a colony blot assay with type strains of 15 Campylobacter and Arcobacter species as well as in a slot blot format using genomic DNA extracted from field strains of C. fetus and C. Hyointestinalis. Two oligonucleotides were constructed for C. fetus that hybridized with equal specificity with each of 57 biochemically confirmed isolates of C. fetus but not with any other Campylobacter species. The C. Hyointestinalis probe reacted with 47 of 48 biochemically confirmed field isolates of C. Hyointestinalis. In Southern blot hybridization of BglII digests of genomic DNA, the respective probes reacted within three restriction fragments of either C. Hyointestinalis (7.2, 8.2, and 10.1 kb) or C. fetus (7.0, 7.7, and 9.0 kb). This suggests multiple copies of genes encoding 16S rRNA. Images

Floyd E. Dewhirst - One of the best experts on this subject based on the ideXlab platform.

  • evidence that the Campylobacter fetus sap locus is an ancient genomic constituent with origins before mammals and reptiles diverged
    Infection and Immunity, 2001
    Co-Authors: Floyd E. Dewhirst, Martin J Blaser
    Abstract:

    Campylobacter fetus bacteria, isolated from both mammals and reptiles, may be either subsp. fetus or subsp. venerealis and either serotype A or serotype B. Surface layer proteins, expressed and secreted by genes in the sap locus, play an important role in C. fetus virulence. To assess whether the sap locus represents a pathogenicity island and to gain further insights into C. fetus evolution, we examined several C. fetus genes in 18 isolates. All of the isolates had 5 to 9 sapA or sapB homologs. One strain (85-387) possessed both sapA and sapB homologs, suggesting a recombinational event in the sap locus between sapA and sapB strains. When we amplified and analyzed nucleotide sequences from portions of housekeeping gene recA (501 bp) and sapD (450 bp), a part of the 6-kb sap invertible element, the phylogenies of the genes were highly parallel. Among the 15 isolates from mammals, serotype A and serotype B strains generally had consistent positions. The fact that the serotype A C. fetus subsp. fetus and subsp. venerealis strains were on the same branch suggests that their differentiation occurred after the type A-type B split. Isolates from mammals and reptiles formed two distinct tight phylogenetic clusters that were well separated. Sequence analysis of 16S rRNA showed that the reptile strains form a distinct phylotype between mammalian C. fetus and Campylobacter Hyointestinalis. The phylogenies and sequence results showing that sapD and recA have similar G + C contents and substitution rates suggest that the sap locus is not a pathogenicity island but rather is an ancient constituent of the C. fetus genome, integral to its biology.

  • Campylobacter hyoilei sp nov associated with porcine proliferative enteritis
    International Journal of Systematic and Evolutionary Microbiology, 1995
    Co-Authors: Malcolm R Alderton, Floyd E. Dewhirst, Victoria Korolik, Peter J Coloe, Bruce J. Paster
    Abstract:

    Campylobacter hyoilei sp. nov. is the name proposed for an organism formerly described as strain RMIT 32AT (T = type strain) and a group of similar bacteria isolated from intestinal lesions of pigs with proliferative enteritis. The phenotypic characteristics of these organisms indicated that they are closely related to each other and are not strains of other Campylobacter spp. commonly isolated from pigs. The results of probing of Cla I-, Eco RV-, or Bg/II-cleaved genomic DNAs from C. hyoilei strains with a radiolabeled DNA probe that distinguishes between Campylobacter jejuni and Campylobacter coli indicated that C. hyoilei and C. coli are closely related. However, the 16S rRNA sequence of the reference strain of C. hyoilei, RMIT 32AT, was four bases different from the 16S rRNA sequence of C. jejuni CCUG 11284T and five bases different from the 16S rRNA sequence of C. jejuni subsp. doylei CCUG 24567T, suggesting that C. hyoilei is more closely related to C. jejuni than to C. coli. Hybridization between DNA from C. hyoilei type strain RMIT 32A and DNAs from selected type and reference strains of other Campylobacter species and subspecies, including C. jejuni, C. jejuni subsp. doylei, C. coli, Campylobacter mucosalis, and Campylobacter Hyointestinalis, as well as the other C. hyoilei strains (the RMIT 32AT-like isolates), revealed that high levels of DNA hybridization (>70%) occurred only between the reference strain and other strains of C. hyoilei.

  • Helicobacter acinonyx sp. nov., isolated from cheetahs with gastritis.
    International journal of systematic bacteriology, 1993
    Co-Authors: Kathryn A. Eaton, Floyd E. Dewhirst, M. J. Radin, James G. Fox, Bruce J. Paster, Steven Krakowka, Douglas R. Morgan
    Abstract:

    Four strains of a novel Helicobacter species were isolated from the stomachs of cheetahs (Acinonyx jubilatus) with gastritis. These isolates were phenotypically similar to Helicobacter pylori. The isolates were gram-negative, spiral bacteria which grew under microaerophilic conditions at 37°C, but not at 25 or 42°C, and produced urease, catalase, oxidase, alkaline phosphatase, and gamma-glutamyl transpeptidase. The isolates did not ferment glucose, mannitol, inositol, sorbitol, rhamnose, sucrose, melibiose, amygdalin, or arabinose; hydrolyze hippurate or indoxyl acetate; or reduce nitrate. They did not produce H2S from triple sugar iron agar, and they did not grow in the presence of 1.0% glycine or 1.5% NaCI. They were resistant to nalidixic acid and sensitive to cephalothin and metronidazole. Cells were typically 0.3 by 2.0 μm and possessed tufts of two to five sheathed, monopolar flagella. The G+C content of strain 90-119 was 30 mol%. Cluster analysis of densitometry scans of polyacrylamide protein gels revealed more than 70% similarity of the cheetah isolates to H. pylori, less than 60% similarity to Helicobacter felis, and less than 50% similarity to Helicobacter mustelae. Complete 16S rRNA sequences were determined for two of the cheetah isolates. Phylogenetic analysis was performed by comparing the cheetah sequences to those of 19 reference strains, including H. pylori, H. felis (two strains), H. mustelae, Helicobacter muridarum, “Flexispira rappini,” Wolinella succinogenes, Campylobacter coli, Campylobacter concisus, Campylobacter curvus, Campylobacter fetus, Campylobacter Hyointestinalis, Campylobacter jejuni, Campylobacter lari, Campylobacter rectus, Campylobacter sputorum subsp. bubulus, a Campylobacter sp. (pigisolate), [Bacteroides] gracilis, and [Bacteroides] ureolyticus. The 16S rRNA sequences for 13 of the 19 reference species have not previously been reported. Phylogenetic analysis demonstrated that the cheetah isolates were most closely related to H. pylori (97.4% similarity), H. felis (96.1% similarity), and H. mustelae (93.4% similarity). On the basis of these findings, we propose that these isolates represents a novel species of Helicobacter, which we designate Helicobacter acinonyx. The type strain is 90-119 (CCUG 29263, ATCC 51101).

  • oligodeoxynucleotide probes for Campylobacter fetus and Campylobacter Hyointestinalis based on 16s rrna sequences
    Journal of Clinical Microbiology, 1991
    Co-Authors: Irene V Wesley, Floyd E. Dewhirst, R D Wesley, M Cardella, Bruce J. Paster
    Abstract:

    Deoxyoligonucleotide probes were constructed for the identification of Campylobacter fetus and Campylobacter Hyointestinalis based on 16S rRNA sequence data. Probes were targeted to hypervariable regions of 16S rRNA. Specificity of oligonucleotide probes was tested in a colony blot assay with type strains of 15 Campylobacter and Arcobacter species as well as in a slot blot format using genomic DNA extracted from field strains of C. fetus and C. Hyointestinalis. Two oligonucleotides were constructed for C. fetus that hybridized with equal specificity with each of 57 biochemically confirmed isolates of C. fetus but not with any other Campylobacter species. The C. Hyointestinalis probe reacted with 47 of 48 biochemically confirmed field isolates of C. Hyointestinalis. In Southern blot hybridization of BglII digests of genomic DNA, the respective probes reacted within three restriction fragments of either C. Hyointestinalis (7.2, 8.2, and 10.1 kb) or C. fetus (7.0, 7.7, and 9.0 kb). This suggests multiple copies of genes encoding 16S rRNA. Images