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B Pot

Publications and source records attributed to B Pot.

46 records · Page 3Linked to original sources

Characterization and identification of Vagococcus fluvialis strains isolated from domestic animals.

Strains of Vagococcus fluvialis, a species of Gram-positive catalase-negative cocci, related to the genera Enterococcus and Carnobacterium, were isolated from various lesions of pigs, from lesions and tonsils of cattle and cats and from tonsils of a horse. Most lesion strains were isolated in mixed culture from animals with disease conditions unrelated to coccal infection. Certain differences with the species description of Vagococcus fluvialis were found: only a proportion of the strains was motile; many strains gave positive reactions to Voges-Proskauer, alkaline phosphatase and leucine arylamidase tests or produced acid from galactose and D-tagatose. SDS-PAGE of whole-cell protein patterns, however, confirmed the phenotypic identification. Guidelines for identification of Vagococcus fluvialis are given and an emended description of the species is proposed.

Animals↗

Identification and classification of Lactobacillus acidophilus, L. gasseri and L. johnsonii strains by SDS-PAGE and rRNA-targeted oligonucleotide probe hybridization.

Thirty-two strains originally identified as Lactobacillus acidophilus and L. gasseri were screened for their taxonomic homogeneity by SDS-PAGE of whole-cell proteins. After numerical comparison of the resulting protein electrophoretic fingerprints, two well-delineated clusters were detected. The majority of the strains grouped in one electrophoretic cluster, which contained the type strain of L. acidophilus and corresponds to DNA group A1 of Johnson, J. L., Phelps, C. F., Cummins, C. S., London, J. & Gasser, F. (1980; International Journal of Systematic Bacteriology 30, 53-68). Another cluster corresponded to DNA group B. It contained two subclusters, which agreed perfectly with DNA subgroups B1 (L. gasseri) and B2 (L. johnsonii), respectively. The 23S rRNA genes were partially sequenced and 23S-rRNA-targeted oligonucleotide probes were designed for identification of DNA groups A1, B1 and B2. Probe Lbg reacted with all strains of electrophoretic cluster B1 (L. gasseri), probe Lbj hybridized with strains of cluster B2 (L. johnsonii) and probe Lba with strains of cluster A1 (authentic L. acidophilus). The probes were successfully used for the identification of strains belonging to the respective species. The phylogenetic relationship of a representative of L. johnsonii was determined by comparative sequence analysis of the 16S rRNA genes. It is very closely related to L. gasseri.

Bacterial Proteins↗

Polyphasic taxonomic study of the emended genus Arcobacter with Arcobacter butzleri comb. nov. and Arcobacter skirrowii sp. nov., an aerotolerant bacterium isolated from veterinary specimens.

The relationships of 77 aerotolerant Arcobacter strains that were originally identified as Campylobacter cryaerophila (now Arcobacter cryaerophilus [P. Vandamme, E. Falsen, R. Rossau, B. Hoste, P. Segers, R. Tytgat, and J. De Ley, Int. J. Syst. Bacteriol. 41:88-103, 1991]) and 6 reference strains belonging to the taxa Arcobacter nitrofigilis, Arcobacter cryaerophilus, and "Campylobacter butzleri" were studied by using a polyphasic approach, in which we performed DNA-rRNA hybridizations, DNA-DNA hybridizations, a numerical analysis of whole-cell protein patterns after sodium dodecyl sulfate-polyacrylamide gel electrophoresis, an analysis of cellular fatty acid compositions, and a phenotypic analysis and determined DNA base ratios. Our results indicate that "C. butzleri" should be transferred to the genus Arcobacter as Arcobacter butzleri comb. nov., as was suggested by Kiehlbauch and coworkers (J. A. Kiehlbauch, D. J. Brenner, M. A. Nicholson, C. N. Baker, C. M. Patton, A. G. Steigerwalt, and I. K. Wachsmuth, J. Clin. Microbiol. 29:376-385, 1991). A rapid screening of all strains in which we used the sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique revealed five major groups, which were identified by using DNA-DNA hybridization data as A. cryaerophilus (two distinct electrophoretic subgroups), A. butzleri, A. nitrofigilis, and a new species, for which we propose the name Arcobacter skirrowii. The phylogenetic position within rRNA superfamily VI was established for each species. A. butzleri strains and strains belonging to one of the electrophoretic subgroups of A. cryaerophilus had similar fatty acid contents. An analysis of fatty acid compositions allowed clear-cut differentiation of all of the other groups. All of the species could be distinguished by using classical phenotypic tests, although erroneous identifications due to a shortage of clear-cut differentiating tests could occur.

Animals↗

Is "Campylobacter upsaliensis" an unrecognised cause of human diarrhoea?

For 3 years a filtration system for the isolation of "new" campylobacter was included in the culture protocol of 15,185 stool specimens. "C upsaliensis" was isolated in 99 patients, C jejuni subsp doylei in 4, and C hyointestinalis in 2. "C upsaliensis" was the only organism isolated in 83 patients. Clinical information was available for 77 out of these 83 patients. 92% of the patients had diarrhoea; vomiting and fever were rare (14% and 7%, respectively); the onset was mostly sudden; and the symptoms usually lasted for less than a week. Gross or occult blood was present in a quarter of cases and neutrophils were detected in faecal smears in about a fifth. "C upsaliensis" may be an unrecognised and frequent cause of diarrhoea in man, and selective isolation media should be combined with non-selective isolation systems.

Adult↗

Interlaboratory comparative study of the numerical analysis of one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoretic protein patterns of Campylobacter strains.

Twenty-nine bacterial strains of the genus Campylobacter were examined independently at two collaborating institutes, the National Collection of Type Cultures, London and the Laboratorium voor Microbiologie, Rijksuniversiteit Gent. The one-dimensional polyacrylamide gel electrophoretic protein patterns of the strains were analysed using computerised numerical methods which employed a correlation coefficient and a clustering algorithm. The electrophoretic methods used at the two institutes included both major differences such as gel composition and running conditions and minor differences in buffer composition. Although the algorithm on which similarity and clustering were computed were the same, the detailed treatment of scan patterns differed. The resulting protein patterns in the gels differed markedly in appearance but after numerical analysis the two systems were equally effective in their ability to speciate the strains. There were, however, differences in the relationships between the species defined at the two institutes and these were at least partly due to the different background subtraction methods employed. In conclusion, the portability and reproducibility of the two systems for identification was demonstrated but for definitive classification further standardization may be required.

Bacterial Proteins↗

Acidovorax, a new genus for Pseudomonas facilis, Pseudomonas delafieldii, E. Falsen (EF) group 13, EF group 16, and several clinical isolates, with the species Acidovorax facilis comb. nov., Acidovorax delafieldii comb. nov., and Acidovorax temperans sp. nov.

Pseudomonas facilis and Pseudomonas delafieldii are inappropriately assigned to the genus Pseudomonas. They belong to the acidovorans rRNA complex in rRNA superfamily III (i.e., the beta subclass of the Proteobacteria). The taxonomic relationships of both of these species, two groups of clinical isolates (E. Falsen [EF] group 13 and EF group 16), and several unidentified or presently misnamed strains were examined by using DNA:rRNA hybridization, numerical analyses of biochemical and auxanographic features and of fatty acid patterns, polyacrylamide gel electrophoresis of cellular proteins, and DNA:DNA hybridization. These organisms form a separate group within the acidovorans rRNA complex, and we propose to transfer them to a new genus, Acidovorax. We describe the following three species in this genus: the type species, Acidovorax facilis (formerly Pseudomonas facilis), with type strain LMG 2193 (= CCUG 2113 = ATCC 11228); Acidovorax delafieldii (for the former Pseudomonas delafieldii and most of the EF group 13 strains), with type strain LMG 5943 (= CCUG 1779 = ATCC 17505); and Acidovorax temperans (for several former Pseudomonas and Alcaligenes strains and most of the EF group 16 strains), with type strain CCUG 11779 (= LMG 7169).

Base Composition↗

Identification of Campylobacter cinaedi isolated from blood and feces of children and adult females.

Five Campylobacter-like organisms isolated from blood and feces were identified by numerical analysis of gel electrophoretic protein profiles and immunotyping as Campylobacter cinaedi. Two of these strains were isolated from adult females; the remaining three strains were isolated from children, two of whom were girls. C. cinaedi has hitherto been isolated only from rectal swabs and blood of homosexual and bisexual males with gastrointestinal symptoms. The results presented extend our knowledge of the features and the habitat of C. cinaedi.

Adult↗

Characterization and description of "Campylobacter upsaliensis" isolated from human feces.

During a 3-year period, "Campylobacter upsaliensis" was isolated from 99 patients. Phenotypic characterization and numerical analysis of protein electrophoregrams showed evidence that "C. upsaliensis" is a distinct Campylobacter species with unique characteristics. The MBCs of 13 antibiotics were determined. In general, these organisms were highly susceptible to drugs that were present in the selective isolation media, making none of the available selective media suitable for the isolation of "C. upsaliensis." Ten strains were found to be resistant to erythromycin (MBCs, greater than or equal to 12.50 mg/liter). Plasmid DNA was detectable in 89 of the 99 strains; 16 plasmid profiles could be identified. Plasmid pattern 16, containing four plasmids of 52, 32, 5.5, and 2.6 megadaltons, represented 60.7% of the plasmid-containing strains. None of the "C. upsaliensis" strains could be agglutinated with antisera against heat-labile antigens from C. jejuni, C. coli, or C. laridis. "C. upsaliensis" was found to be susceptible to serum killing and was readily phagocytized by human polymorphonuclear cells.

Bacterial Proteins↗

Identification of EF group 22 campylobacters from gastroenteritis cases as Campylobacter concisus.

EF (E. Falsen) group 22, a group of Campylobacter strains sorted out by routine immunotyping among unidentified or misidentified human nonoral clinical specimens, was characterized by numerical analysis of gel electrophoretic protein profiles and immunotyping. The protein electrophoretic and immunotyping analyses, DNA:DNA hybridizations, and the DNA base composition demonstrated unambiguously that all EF group 22 strains belong to Campylobacter concisus. EF group 22 strains have DNA binding values of at least 42% with the type strain of C. concisus, showing a considerable degree of genomic heterogeneity. The isolation from blood, esophagus, stomach, duodenum, and feces of humans in association with different gastrointestinal disorders considerably extends the clinical significance of this species. Our results indicate that sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunotyping are excellent tools for the identification of the fastidious C. concisus strains and relatives.

Adult↗