Biomedical subjects

R A Hutson

Publications and source records attributed to R A Hutson.

At least 37 records · Page 2Linked to original sources

PubMed1998

Corynebacterium camporealensis sp. nov., associated with subclinical mastitis in sheep.

Four strains of a hitherto-unknown catalase-positive, facultatively anaerobic Corynebacterium species were isolated from the milk of sheep affected by subclinical mastitis. The most characteristic phenotypic reactions of the four strains were their weak fermentative acid production from glucose, their failure to produce acid from mannitol, xylose, sucrose and maltose, and a strong CAMP reaction with Staphylococcus aureus. Chemotaxonomic investigations revealed the presence of a cell wall based on meso-diaminopimelic acid and short-chain mycolic acids, which is consistent with the genus Corynebacterium. A comparative 16S rRNA gene sequence analysis confirmed that the organisms from sheep were members of the genus Corynebacterium, where they formed a distinct subline, exhibiting > 4% sequence divergence with other known Corynebacterium species. Based on both phenotypic and phylogenetic findings, a new species, Corynebacterium camporealensis, is proposed. The type strain of Corynebacterium camporealensis is CECT 4897 (= CRS-51T).

Animals↗

PubMed1998

Actinobacillus scotiae sp. nov., a new member of the family Pasteurellaceae Pohl (1979) 1981 isolated from porpoises (Phocoena phocoena).

Phenotypic and phylogenetic studies were performed on a Gram-negative, rod-shaped bacterium isolated from three porpoises. Biochemical and physiological studies indicated that the bacterium was related to the family Pasteurellaceae. Comparative 16S rRNA gene sequencing studies confirmed these findings and demonstrated that the bacterium represents a hitherto unknown subline. The nearest phylogenetic relative of the unknown bacterium was Actinobacillus delphinicola, an organism also originating from sea mammals, although a sequence divergence of 3% demonstrated that the newly isolated bacterium is a distinct species. On the basis of the results of the phylogenetic analysis and phenotypic criteria, it is proposed that the bacterium should be classified as a new species, Actinobacillus scotiae sp. nov. The type strain of Actinobacillus scotiae sp. nov. is NCTC 12922T (= M2000/95/1T).

Actinobacillus↗

PubMed1998

Description of Gemella sanguinis sp. nov., isolated from human clinical specimens.

Six strains of a hitherto undescribed gram-positive, catalase-negative, facultatively anaerobic coccus isolated from human sources were characterized by phenotypic and molecular taxonomic methods. Comparative 16S rRNA gene sequencing studies demonstrated that the unknown strains were genealogically identical and constitute a new subline within the genus Gemella. The unknown bacterium was readily distinguished from Gemella haemolysans, Gemella bergeriae, and Gemella morbillorum by biochemical tests and electrophoretic analysis of whole-cell proteins. Based on phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium be classified as Gemella sanguinis sp. nov. The type strain is CCUG 37820(T).

DNA, Bacterial↗

PubMed1998

Gemella bergeriae sp. nov., isolated from human clinical specimens.

Six strains of a hitherto-undescribed gram-positive, catalase-negative, facultatively anaerobic coccus from human sources were characterized by phenotypic and molecular taxonomic methods. Comparative 16S rRNA gene sequencing studies demonstrated that the unknown strains are genealogically homogeneous and constitute a new subline within the genus Gemella. The unknown bacterium was readily distinguished from Gemella haemolysans, the type species of the genus Gemella, and from Gemella morbillorum by biochemical tests and electrophoretic analysis of whole-cell proteins. On the basis of phylogenetic and phenotypic evidence, it is proposed that the unknown bacterium from clinical specimens be classified as Gemella bergeriae sp. nov. The type strain of G. bergeriae is CCUG 37817 (= strain 617-93).

DNA, Bacterial↗

PubMed1997

Corynebacterium lipophiloflavum sp. nov. isolated from a patient with bacterial vaginosis.

A unique coryneform bacterium was isolated from a patient with bacterial vaginosis. Chemotaxonomical investigations demonstrated that the unknown bacterium belonged to the genus Corynebacterium. The yellow-pigmented, slightly lipophilic, oxidative, urea-hydrolyzing bacterium could be phenotypically readily differentiated from the other members of the genus Corynebacterium. Comparative 16S rRNA gene analysis revealed that the bacterium represented a new subline within the genus Corynebacterium for which the name Corynebacterium lipophiloflavum sp. nov. is proposed. The type strain is CCUG 37336 (DSM 44291).

Adult↗

PubMed1997

Determination of immunological homology between cellulosome subunits and cloned endoglucanases and xylanase of Clostridium thermocellum.

Immuno-cross reactivity between the subunits of Clostridium thermocellum cellulosome and cloned endogucanases and xylanase from the same bacterium was studied using the polyclonal antibodies raised against cloned enzymes. Dot blot analysis showed that the cellulosome, S8 and S11 subunits cross-reacted strongly with the antibodies of all cloned enzymes tested except that raised against CelC. Western blot analysis revealed that S8 and S11 subunits cross-reacted with the antibodies of CelA, CelB, CelD, CelG, CelH and XynZ, but the antibodies of CelB and CelG were highly specific for S8 and S11 subunits, respectively. Similar analysis using dissociated cellulosome showed that the antibodies of all cloned enzymes tested cross-reacted with more than one subunit of the cellulosome. Antibodies of CelC showed a very low cross-reactivity against all subunits of the cellulosome. The results indicate that immunological cross-reactivity studies could be useful, not only for demonstrating the similarities between native and cloned enzymes, but also for identifying native enzymes using antibodies of cloned enzymes.

Journal Article↗

PubMed1997

Staphylococcus lutrae sp. nov., a new coagulase-positive species isolated from otters.

Phenotypic and phylogenetic studies were performed with three strains of a catalase-positive, gram-positive, coccus-shaped bacterium isolated from otters. The results of a 16S rRNA gene sequence analysis demonstrated that these strains represent a hitherto unknown subline within the genus Staphylococcus. Based on the results of the phylogenetic analysis and phenotypic criteria, we propose that these bacteria should be classified as members of a new species, Staphylococcus lutrae. The type strain of S. lutrae is DSM 10244.

Animals↗

PubMed1997

Corynebacterium mastitidis sp. nov., isolated from milk of sheep with subclinical mastitis.

Fourteen strains of a hitherto unknown catalase-positive, aerobic, gram-positive coryneformlike organism were isolated from the milk of sheep with subclinical mastitis from different regions of Spain. The strains phenotypically closely resembled one another and biochemically were similar to Corynebacterium urealyticum and Corynebacterium afermentans subsp. lipophilum. The results of chemotaxonomic investigations were consistent with membership in the genus Corynebacterium, and comparative 16S rRNA gene sequencing studies showed that the unknown bacterium from sheep was indeed a member of the genus Corynebacterium. Within the genus Corynebacterium the new bacterium formed a distinct subline that exhibited > 4% sequence divergence with other species. Based on both phenotypic and phylogenetic findings, a new species, Corynebacterium mastitidis, is proposed for the organisms from mastitic sheep. The type strain of C. mastitidis is CECT 4843 (= S-8).

Animals↗

PubMed1997

Corynebacterium imitans sp. nov. isolated from patients with suspected diphtheria.

A 5-month-old boy of a Romanian family traveling via Ukraine to Poland developed a respiratory disease that resembled and that was initially diagnosed as pharyngeal diphtheria. The child recovered after treatment with antidiphtheria antitoxin. A coryneform bacterium had been isolated from a nasopharyngeal specimen from the child and was initially identified as an atypical Corynebacterium diphtheriae strain. Seven adults who had contact with either the child or an adult contact person also developed symptoms of pharyngeal diphtheria, were also treated with antitoxin, and recovered uneventfully. Coryneform bacteria similar to that originating from the index patient were also isolated from the throat swabs of three adults. Detailed biochemical and chemotaxonomic investigations revealed that the coryneform bacteria belonged to the genus Corynebacterium and could be differentiated from all other defined species of this genus. Ribotyping and pulsed-field gel electrophoresis demonstrated that all four patients' isolates were of clonal origin. The diphtheria toxin gene and its product were not detected either by PCR assays or by the Elek test, making a possible disease association of the Corynebacterium more unlikely. Comparative 16S rRNA gene sequence analysis revealed that the coryneform bacterium represented a new subline within the genus Corynebacterium, for which the name Corynebacterium imitans sp. nov. is proposed. The type strain is NCTC 13015 (DSM 44264; CCUG 36877).

Corynebacterium↗

PubMed1996

Genetic characterization of Clostridium botulinum type A containing silent type B neurotoxin gene sequences.

A recent study detected genes encoding type B botulinum neurotoxin in some type A strains of Clostridium botulinum that exhibit no type B toxin activity. In this study, we investigated the presence, structure, linkage, and organization of genes encoding botulinum neurotoxin (BoNT) and other components of the progenitor complex. Sequence analysis showed that the silent BoNT/B gene is highly related to that from authentic proteolytic type B C. botulinum. However, a stop signal and deletions were found within the sequence. A non-toxin nonhemagglutinin gene (NTNH) was mapped immediately upstream of both the BoNT/A and silent BoNT/B genes. Significantly the NTNH gene adjacent to the defective BoNT/B gene was "chimeric, " the 5'- and 3'-regions of the gene had high homology with corresponding regions of the type B NTNH gene, while the 471-amino acid sequence in the central region was identical to NTNH of type A. Hemagglutinin genes HA-33 and HA-II were not found adjacent to the NTNH/A gene, but instead there was an unidentified open reading frame previously reported in strains of C. botulinum types E and F. By contrast HA-II, HA-33, and NTNH genes were located immediately upstream of the silent BoNT/B gene. Pulsed-field gel electrophoretic analysis of chromosomal DNA digests indicated the distance between type A and B gene clusters to be less than 40 kilobases.

Amino Acid Sequence↗

PubMed1996

Isolation of Arthrobacter spp. from clinical specimens and description of Arthrobacter cumminsii sp. nov. and Arthrobacter woluwensis sp. nov.

Arthrobacter spp. are very widely distributed in the environment (e.g., soil) but have not been described as causing disease in humans. Over a 6-year period, two reference laboratories isolated or received 11 strains which were eventually identified as belonging to the genus Arthrobacter. These strains had been initially identified as Centers for Disease Control and Prevention coryneform group B-1 and B-3 bacteria (whitishgrayish colonies of 2 mm or greater in diameter after 24 h of incubation, respiratory metabolism, absent or weak acid production from sugars, and hydrolysis of gelatin). However, chemotaxonomic investigations revealed lysine as the diamino acid of the cell wall and the presence of branched cellular fatty acids (with anteiso-pentadecanoic acid predominating) which was compatible with an assignment of the 11 isolates to the genus Arthrobacter only. Peptidoglycan and 16S rRNA gene sequence analyses demonstrated that three of the strains studied were representatives of a new Arthrobacter species for which the name Arthrobacter cumminsii sp. nov. is proposed and that one other strain represented a second new Arthrobacter species for which the name Arthrobacter woluwensis sp. nov. is proposed. This report is the first on the isolation of Arthrobacter spp. from clinical specimens.

Arthrobacter↗

PubMed1995

Bacillus oleronius sp.nov., a member of the hindgut flora of the termite Reticulitermes santonensis (Feytaud).

A new rod-shaped endospore-forming bacterium is described, which was isolated from the hindgut of the termite Reticulitermes santonensis (Feytaud). The isolate stains Gram negative and its DNA has a guanine-plus-cytosine content of 35 mol%. Despite the Gram-staining reaction, both biochemical and physiological features place the isolate in the genus Bacillus and indicate a phenotypic resemblance to the Bacillus firmus-lentus group of species. On the basis of comparative 16S rRNA analysis and some phenotypic features the isolate clearly represents a new species for which the name Bacillus oleronius is proposed. The type strain is Bacillus oleronius Rt 10 (DSM 9356).

Animals↗

PubMed1994

Nucleotide sequence of the gene coding for non-proteolytic Clostridium botulinum type B neurotoxin: comparison with other clostridial neurotoxins.

The neurotoxin gene of non-proteolytic Clostridium botulinum type B (strain Eklund 17B) was cloned as a series of overlapping polymerase chain reaction (PCR) fragments generated with primers designed to conserved regions of published botulinal toxin (BoNT) sequences. The 3' end of the gene was obtained by using primers designed to the determined sequence of non-proteolytic BoNT/B and a published downstream region of BoNT/B gene from a proteolytic strain. Translation of the nucleotide sequence derived from cloned PCR fragments demonstrated the toxin gene encodes a protein of 1291 amino acid residues. Comparative alignment of the derived BoNT/B sequence with those of other published botulinal neurotoxins revealed highest sequence relatedness with BoNT/B of proteolytic C. botulinum. The sequence identity between non-proteolytic and proteolytic BoNT/B was 97.7% for the light chain (corresponding to 10 amino acid changes) and 90.2% for the heavy chain (corresponding to 81 amino acid changes), with most differences occurring at the C-terminal end. A genealogical tree constructed from all known botulinal neurotoxin sequences revealed marked topological differences with a phylogenetic tree of C. botulinum types based upon small-subunit (16S) ribosomal RNA sequences.

Amino Acid Sequence↗

PubMed1993

Towards a phylogeny of the clostridia based on 16S rRNA sequences.

The 16S rRNA sequences of 17 species of the genus Clostridium were determined by direct sequencing of their PCR amplified genes. The sequences were aligned with those from other known clostridial species and representative low G + C Gram-positive relatives, and a phylogenetic tree was constructed. It was evident from the comparative sequence analysis that the genus Clostridium as presently constituted is phylogenetically extremely heterogeneous. This study corroborates and extends earlier findings in showing that many non-sporeforming bacteria are phylogenetically closely intermixed with Clostridium species. The taxonomic implications of the phylogenetic findings are discussed.

Clostridium↗

PubMed1993

Nucleotide sequence of the gene coding for Clostridium barati type F neurotoxin: comparison with other clostridial neurotoxins.

The neurotoxin gene from Clostridium barati ATCC43756 was cloned as a series of overlapping polymerase chain reaction (PCR) generated fragments using primers designed to conserve toxin sequences previously published. The toxin gene has an open reading frame (ORF) of 1268 amino acids giving a calculated molecular mass of 141,049 Da. The sequence identity between the C. barati ATCC43756 and non-proteolytic C. botulinum 202F neurotoxins is 64.2% for the light chain and 73.6% for the heavy chain. This is much lower than reported identities for the type E neurotoxins from C. botulinum and C. butyricum (96% identity between light chains and 98.8% between the heavy chains). Previously identified conserved regions in other botulinal neurotoxins were also conserved in that of C. barati. An ORF upstream of the toxin coding region was revealed. This shows strong homology to the 3' end of the gene coding for the nontoxic-nonhemagglutinin (NTNH) component of the progenitor toxin from C. botulinum type C neurotoxin.

Amino Acid Sequence↗

PubMed1993

Genetic interrelationships of saccharolytic Clostridium botulinum types B, E and F and related clostridia as revealed by small-subunit rRNA gene sequences.

The phylogenetic interrelationships of saccharolytic C. botulinum types B, E and F together with eleven other saccharolytic clostridia were examined by 16S rRNA gene sequencing. Comparative analysis of the sequence data revealed that the saccharolytic C. botulinum types B, E and F were highly related and represent a single genetic group. Strains of C. barati and C. butyricum that produce botulinal neurotoxin revealed almost 100% 16S rRNA sequence identity with their respective non-toxigenic counterparts and were phylogenetically distinct from saccharolytic C. botulinum (types B, E and F). Proteolytic C. botulinum type F was shown to be phylogenetically remote from the saccharolytic C. botulinum group. The implications of the sequence data for the taxonomy of the C. botulinum complex are discussed.

Base Sequence↗

PubMed1993

The development and assessment of DNA and oligonucleotide probes for the specific detection of Bacillus anthracis.

Two DNA probes and a number of oligonucleotide probes were designed from the virulence factor genes of Bacillus anthracis. These probes were tested for specificity against 52 B. anthracis strains and 233 Bacillus strains encompassing 23 other species. A rapid slot blotting technique was used for screening the large numbers of isolates involved. All probes tested appeared to be specific for B. anthracis under high stringency conditions. These probes could differentiate between virulent and avirulent strains. The probes were also applied to the detection of B. anthracis in routine environmental and clinical samples. A non-radioactive hybridization and detection system based on digoxigenin-11-dUTP was developed.

Bacillus anthracis↗

PubMed1992

Bacillus anthracis but not always anthrax.

Gram-positive bacilli isolated during epidemiological investigations which, on the basis of conventional tests, resemble Bacillus anthracis but which fail to produce the capsule or to induce anthrax in test animals have long been dismissed in clinical and veterinary laboratories as B. cereus or simply as unidentified Bacillus spp. and thereupon discarded as inconsequential. In this study, the application of newly available DNA probe, polymerase chain reaction and specific toxin antigen detection technology has revealed that a proportion of such strains are B. anthracis which lack the plasmid carrying the capsule gene (pXO2). While these techniques cannot, of course, be used to confirm the identities of strains resembling B. anthracis but which also lack the plasmid carrying the toxin genes (pXO1), the likelihood that these also are bona fide B. anthracis becomes more acceptable. (As yet no naturally occurring pXO1-/2+ strains have been found.) At this point, the significance of the presence of such avirulent forms of B. anthracis in specimens can only be a subject for speculation, but the possibility that they may be indicators of virulent parents somewhere in the system being examined must be considered.

Animals↗