Biomedical subjects

K Kersters

Publications and source records attributed to K Kersters.

At least 73 records · Page 4Linked to original sources

PubMed1994

Classification of Pseudomonas diminuta Leifson and Hugh 1954 and Pseudomonas vesicularis Büsing, Döll, and Freytag 1953 in Brevundimonas gen. nov. as Brevundimonas diminuta comb. nov. and Brevundimonas vesicularis comb. nov., respectively.

The taxonomic positions of strains previously assigned to Pseudomonas diminuta and Pseudomonas vesicularis were investigated by a polyphasic approach. The results of DNA-rRNA hybridization studies indicated that these two species belong to a separate genus in the alpha subclass (rRNA superfamily IV) of the Proteobacteria, for which the name Brevundimonas is proposed. Genus delineation and species delineation were determined by comparing the results of numerical analyses of whole-cell protein patterns, fatty acid compositions, and phenotypic characteristics and by measuring DNA base ratios and degrees of DNA relatedness. Taxonomic characteristics of Brevundimonas diminuta and Brevundimonas vesicularis strains were compared with characteristics of reference strains belonging to the following phylogenetically related taxa: a group of organisms gathered in Enevold Falsen group 21, the genera Sphingomonas and Rhizomonas, and the generically misclassified organisms [Pseudomonas] echinoides and "[Pseudomonas] riboflavina."

Animals↗

PubMed1994

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↗

PubMed1994

Flavobacterium meningosepticum, a pathogen in birds.

Five bacterial isolates were recovered from various diseased birds (chickens, a pigeon, and a zebra finch) and were identified as Flavobacterium meningosepticum. Four of them were isolated in pure or nearly pure culture of samples from internal organs, and one strain was isolated in mixed culture of a tarsal joint fluid sample. Except for the last case, there was no evidence of other disease agents. By using phenotypic, chemotaxonomic, and genomic methods, the strains were taxonomically characterized and could not be differentiated from the human clinical reference strains of the species. Two avian strains were different in their phenotypic behaviors and constituted another genotypic subgroup. In general, all F. meningosepticum strains constituted a single species which was easily differentiated from biochemically similar species and phylogenetically closely related taxa.

Animals↗

PubMed1994

Bacteremia caused by a novel Bordetella species, "B. hinzii".

Bordetella spp. cause respiratory tract diseases in warm-blooded animals. Only Bordetella bronchiseptica has been reported to cause bacteremia in humans, and this rare infection usually occurs with pneumonia in immunocompromised patients. We describe "Bordetella hinzii" bacteremia in an AIDS patient without a respiratory illness. Combining biochemical phenotyping with fatty acid analysis permitted preliminary identification of this previously undescribed pathogen; identity was confirmed by DNA-DNA hybridization. This report extends the spectrum of human infections caused by the bordetellae.

Adult↗

PubMed1993

Balneatrix alpica gen. nov., sp. nov., a bacterium associated with pneumonia and meningitis in a spa therapy center.

In 1987, an outbreak of pneumonia and meningitis caused by an unknown bacterium occurred in a spa therapy centre. Nine isolates of this pathogen constituted a tight DNA hybridization group. rRNA-DNA hybridization and 16S rRNA sequencing showed that the studied bacteria represented a new branch in superfamily II (= gamma subclass) of the Proteobacteria, close to the genus Oceanospirillum. The new bacterium was highly polymorphic and, in young cultures, had curved Gram-negative cells, motile by polar single flagella. The new bacterium differed from the genus Oceanospirillum by its lacking the NaCl requirement and by reducing nitrate into nitrite, producing indole from tryptophan and producing acid from carbohydrates. The name Balneatrix alpica gen. nov., sp. nov. is proposed for the studied organism. The type strain is strain 4-87 (= CIP 103589).

Balneology↗

PubMed1993

Moraxella lincolnii sp. nov., isolated from the human respiratory tract, and reevaluation of the taxonomic position of Moraxella osloensis.

A polyphasic taxonomic study was performed to determine the relationships of 10 Moraxella-like strains isolated mainly from the human respiratory tract in Sweden. Two of the strains formed a separate subgroup on the basis of both their protein contents and their fatty acid contents. However, the overall protein and fatty acid profiles revealed that all 10 strains were highly related. Representative strains of the two subgroups exhibited high DNA binding values (98%) with each other and had an identical DNA base ratio (44 mol% G+C). DNA-rRNA hybridizations revealed that this taxon can be included in the genus Moraxella, which is only distantly related to phenotypically similar genera, such as the genera Neisseria and Kingella. The results of an extensive phenotypic analysis indicated that the general biochemical profile of the 10 strains conforms with the description of the genus Moraxella given in Bergey's Manual of Systematic Bacteriology. We therefore consider these organisms members of a new Moraxella species, for which the name Moraxella lincolnii is proposed. Furthermore, we also conclude that Moraxella osloensis belongs, genotypically as well as phenotypically, to the genus Moraxella.

Adult↗

PubMed1993

Neisseria weaveri sp. nov. (formerly CDC group M-5), from dog bite wounds of humans.

The taxonomic relationships of strains belonging to Centers for Disease Control group M-5 were examined. Previous studies of rRNA cistron similarities placed this organism on the Neisseriaceae rRNA branch of rRNA superfamily III; the closest neighbors included the genus Neisseria and groups EF-4a and EF-4b. The group M-5 strains were characterized by a range of phenotypic tests, and their G + C contents and DNA-DNA relatedness levels were determined. In addition, a numerical taxonomic analysis of the whole-cell protein patterns (obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) of group M-5 and related taxa was performed. The strains studied included 45 group M-5 strains, the type strains of six Neisseria species or subspecies, three group EF-4a reference strains, and three group EF-4b reference strains plus the type strain of the phenotypically similar organism Oligella urethralis. Our results showed that the group M-5 strains were members of a homogeneous taxon distinct from phylogenetically closely related taxa. The genomic divergence as revealed by levels of rRNA cistron similarity and phenotypic characteristics indicate that group M-5 can be considered a new species of the genus Neisseria. We therefore propose the new species Neisseria weaveri, with NCTC 12742 (= CCUG 4007 = ISL775/91 = LMG 5135) as the type strain. N. weaveri strains are strictly aerobic, gram-negative, nonmotile, rod-shaped organisms which are catalase and oxidase positive, nonsaccharolytic, and able to grow on MacConkey agar and do not reduce nitrate but generally reduce nitrite.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Riemerella anatipestifer gen. nov., comb. nov., the causative agent of septicemia anserum exsudativa, and its phylogenetic affiliation within the Flavobacterium-Cytophaga rRNA homology group.

The phylogenetic position of the causative agent of septicemia anserum exsudativa, now most often referred to as [Moraxella] anatipestifer (brackets indicate a generically misnamed taxon) or "[Pasteurella] anatipestifer," was established by performing rRNA cistron similarity studies. [Moraxella] anatipestifer belongs to rRNA superfamily V, together with the genera Flavobacterium, Cytophaga, Flexibacter, Weeksella, Capnocytophaga, and Sphingobacterium. The detailed structure of rRNA superfamily V, which now contains five major rRNA homology groups, is described. An analysis of various phenotypic parameters, including new data (cellular proteins and fatty acids) and previously published data (respiratory quinones, enzyme activities, and classical phenotypic features), revealed that [Moraxella] anatipestifer differs in many aspects from its closest relatives, Flavobacterium indologenes, Flavobacterium gleum, Flavobacterium indoltheticum, Flavobacterium balustinum, Flavobacterium meningosepticum, and Weeksella zoohelcum. The combined genotypic and phenotypic data indicate that this organism should be placed in a separate genus; the name Riemerella anatipestifer gen. nov., comb. nov. is proposed for this bacterium. The specific epithet anatipestifer is kept in order to avoid nomenclatural confusion. However, it should be emphasized that the illness caused by this organism is a septicemic disease which is not restricted to ducks.

Animals↗

PubMed1993

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↗

PubMed1993

Detection of the outer membrane lipoprotein I and its gene in fluorescent and non-fluorescent pseudomonads: implications for taxonomy and diagnosis.

The open reading frame of the OprI lipoprotein gene from Pseudomonas aeruginosa was amplified by polymerase chain reaction (PCR) starting from purified DNA or colony lysates. A fragment of the expected size (249 bp) was detected in all P. aeruginosa strains from various clinical and geographical origins. The gene could only be amplified in pseudomonads of rRNA group I which are considered to be the authentic genus Pseudomonas. Digestions with HaeIII, PvuII and SphI of the amplified fragments demonstrated a sequence variation in the oprI gene. Colony, dot and Western blots with two monoclonal antibodies (mAbs) against the lipoprotein I confirmed our PCR results. These findings open interesting perspectives for the molecular taxonomy of the genus Pseudomonas and the development of diagnostic tools.

Antibodies, Monoclonal↗

PubMed1993

Discrimination of epidemic and sporadic isolates of Arcobacter butzleri by polymerase chain reaction-mediated DNA fingerprinting.

DNA polymorphisms of Arcobacter butzleri outbreak-related strains and Arcobacter reference strains were determined by use of the polymerase chain reaction with primers aimed at repetitive sequences. The epidemiological relationship among 14 outbreak-related strains was substantiated, as they showed virtually no genomic variations. Their DNA amplification patterns were, however, clearly different from those of all Arcobacter reference strains studied; each reference strain was characterized by a unique DNA fingerprint.

Animals↗

PubMed1992

Rapid identification of bacteria of the Comamonadaceae with amplified ribosomal DNA-restriction analysis (ARDRA).

Ribosomal rRNA gene fragments (rDNA) encompassing the 16S rDNA, the 16S-23S rDNA spacer region and part of the 23S rDNA of 95 strains belonging to 13 well-described taxa of the eubacterial family Comamonadaceae (beta subclass of the Proteobacteria or rRNA superfamily III) were enzymatically amplified using conserved primers. The fragments of approximately 2400 base pairs were subjected to restriction analysis. Restriction fragment length patterns obtained with HinfI enabled us to distinguish 9 of the 13 taxa studied. Restriction with CfoI was necessary to differentiate Acidovorax delafieldii from A. temperans and Hydrogenophaga flava from H. pseudoflava. The results indicate that amplified rDNA restriction analysis is a simple and reliable tool for the identification of bacterial species.

Base Sequence↗

PubMed1992

The application of whole-cell protein electrophoresis for the classification and identification of basidiomycetous yeast species.

The relationships among 65 basidiomycetous yeast strains were determined by one-dimensional electrophoresis of SDS-solubilized whole-cell proteins. Protein profiles were compared by the Pearson product moment correlation coefficient (r). The strains investigated represented species from the genera Cystofilobasidium, Filobasidium, Filobasidiella, Kondoa, Leucosporidium, Mrakia and Rhodosporidium. Except for the genus Mrakia, all species constituted separate protein electrophoretic clusters. The species of the genus Mrakia (M. frigida, M. gelida, M. nivalis and M. stokesii) show highly similar protein patterns, suggesting that these four species may be synonymous. Strains of two varieties of Filobasidiella neoformans, F. neoformans var. neoformans and F. neoformans var. bacillispora, could not be differentiated by protein electrophoresis. For the delineation of the protein electrophoretic clusters of the yeasts studied, literature data relying on other criteria, such as DNA base composition, carbon source utilization patterns, enzymatic protein electrophoregrams, ubiquinone systems, DNA-DNA homology and rRNA sequence data were used. It was demonstrated that a database of SDS-protein patterns provides a valuable tool for the identification of yeasts.

Bacterial Proteins↗

PubMed1992

DNA probes for Bordetella species and a colorimetric reverse hybridization assay for the detection of Bordetella pertussis.

Three oligonucleotide probe sequences were inferred from the 16S ribosomal ribonucleic acid (rRNA) and the 16S-23S rRNA spacer sequences of Bordetella pertussis ATCC 10380. These probes were used in hybridization tests with deoxyribonucleic acid from Bordetella species and other relevant bacterial taxa. A probe from the spacer region hybridized exclusively to the B. pertussis strains tested and not to strains from other species. Using a combination of three probes, B. pertussis, B. parapertussis/B. bronchiseptica and B. avium could be specifically identified and differentiated from other taxa. Differentiation between B. parapertussis and B. bronchiseptica was not possible with the probes used. Using the spacer probe, a colorimetric hybridization assay specific for B. pertussis was developed based on enzymatic amplification of the 16S-23S rRNA spacer and reverse hybridization in microtitre wells. As compared with results using agarose gel electrophoresis, and Southern and dot-spot hybridization with a 32P-labelled probe, this assay proved to be faster and easier to perform and was found to be at least as sensitive and specific.

Base Sequence↗

PubMed1992

Transfer of several phytopathogenic Pseudomonas species to Acidovorax as Acidovorax avenae subsp. avenae subsp. nov., comb. nov., Acidovorax avenae subsp. citrulli, Acidovorax avenae subsp. cattleyae, and Acidovorax konjaci.

DNA-rRNA hybridizations, DNA-DNA hybridizations, polyacrylamide gel electrophoresis of whole-cell proteins, and a numerical analysis of carbon assimilation tests were carried out to determine the relationships among the phylogenetically misnamed phytopathogenic taxa Pseudomonas avenae, Pseudomonas rubrilineans, "Pseudomonas setariae," Pseudomonas cattleyae, Pseudomonas pseudoalcaligenes subsp. citrulli, and Pseudomonas pseudoalcaligenes subsp. konjaci. These organisms are all members of the family Comamonadaceae, within which they constitute a separate rRNA branch. Only P. pseudoalcaligenes subsp. konjaci is situated on the lower part of this rRNA branch; all of the other taxa cluster very closely around the type strain of P. avenae. When they are compared phenotypically, all of the members of this rRNA branch can be differentiated from each other, and they are, as a group, most closely related to the genus Acidovorax. DNA-DNA hybridization experiments showed that these organisms constitute two genotypic groups. We propose that the generically misnamed phytopathogenic Pseudomonas species should be transferred to the genus Acidovorax as Acidovorax avenae and Acidovorax konjaci. Within Acidovorax avenae we distinguished the following three subspecies: Acidovorax avenae subsp. avenae, Acidovorax avenae subsp. cattleyae, and Acidovorax avenae subsp. citrulli. Emended descriptions of the new taxa are presented.

DNA, Bacterial↗

PubMed1992

Biodegradation of polyhydroxyalkanoates.

Degradation of poly(3-hydroxybutyrate) and copolymers with 3-hydroxyvaleric acid was investigated in natural environments, and the microorganisms involved were isolated and identified. The influence of abiotic and biotic factors on the degradation is discussed.

Bacteria↗

PubMed1992

Outbreak of recurrent abdominal cramps associated with Arcobacter butzleri in an Italian school.

In the autumn of 1983, an outbreak of recurrent abdominal cramps occurred in a nursery and primary school in the Rovigo area in Italy. None of the 10 affected children had diarrhea. An atypical Campylobacter-like organism was isolated from feces in all cases. Conventional enteropathogens were searched for but not detected. The Campylobacter-like organism was identified as Arcobacter butzleri by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins and cellular fatty acid analysis. Its identity was confirmed by DNA-DNA hybridizations versus Arcobacter reference strains. All of the preserved outbreak strains have identical protein profiles and phenotypic characteristics and belong to serogroup 1 of the Lior serotyping scheme on the basis of slide agglutination of crude and absorbed antisera of A. butzleri reference strains versus heat-labile antigens of live bacteria. These data point to an epidemiological relationship. The successive timing of the cases suggests person-to-person transmission.

Campylobacter↗

PubMed1991

Rahnella aquatilis, a potential contaminant in lager beer breweries.

The species Rahnella aquatilis has been isolated mostly from water, soil, and, in a few cases, from human clinical specimens; little is known about its ecological role. The application of polyacrylamide gel electrophoresis of soluble proteins, DNA-DNA hybridizations and API 20 E systems has shown that Rahnella aquatilis might also be encountered as a contaminant in lager beer breweries.

Bacterial Proteins↗