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Pulmonary problems associated with the use of polytetrafluoroethylene.

The experience of a group of nine men employed in a manufacturing plant, who developed attacks of illness during the course of working with polytetrafluoroethylene (PTFE), is reported. The cause was presumed to be the inhalation of fumes from PTFE-contaminated cigarettes. Eight of the nine employees reported chest pain, shortness of breath, and cough. One had documented pulmonary edema. In view of the potential seriousness of the respiratory complications reported by use and by others we raise the question whether "polymerfume fever" is an adequate or appropriate term to apply to the human inhalation reaction to pyrolysis products of PTFE. Under some conditions of PTFE use, special precautions need to be taken, in addition to those usually recommended, to prevent exposure of to this substance.

Hot Temperature↗

The organic preservation of fossil arthropods: an experimental study.

Modern arthropod cuticles consist of chitin fibres in a protein matrix, but those of fossil arthropods with an organic exoskeleton, particularly older than Tertiary, contain a dominant aliphatic component. This apparent contradiction was examined by subjecting modern cockroach, scorpion and shrimp cuticle to artificial maturation (350 degrees C/700 bars/24 h) following various chemical treatments, and analysing the products with pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Analysis of artificially matured untreated cuticle yielded moieties related to phenols and alkylated substituents, pyridines, pyrroles and possibly indenes (derived from chitin). n-Alkyl amides, C16 and C18 fatty acids and alkane/alk-1-ene homologues ranging from C9 to C19 were also generated, the last indicating the presence of an n-alkyl component, similar in composition to that encountered in fossil arthropods. Similar pyrolysates were obtained from matured pure C16 and C18 fatty acids. Py-GC/MS of cuticles matured after lipid extraction and hydrolysis did not yield any aliphatic polymer. This provides direct experimental evidence that lipids incorporated from the cuticle were the source of aliphatic polymer. This process of in situ polymerization appears to account for most of the fossil record of terrestrial arthropods as well as marine arthropods that lacked a biomineralized exoskeleton.

Animals↗

Proposed minimal standards for the genus Mycobacterium and for description of new slowly growing Mycobacterium species.

In accordance with Recommendation 30b of the International Code of Nomenclature of Bacteria, which calls for the development of recommended minimal standards for describing new species, we propose minimal standards for describing the genus Mycobacterium and new slowly growing species of this genus. The minimal standards for assignment of a strain to the genus Mycobacterium include acid-alcohol fastness, a DNA G+C content in the range from 61 to 71 mol%, and mycolic acid detection with characterization of C22 to C26 pyrolysis esters. The recommended minimal standards for describing a new slowly growing Mycobacterium species are based on the results of phenotypic and genomic studies and include the results of the following conventional tests: growth at 25, 30, 33, 37, 42, and 45 degrees C; pigmentation; resistance to isoniazid, thiophene-2-carboxylic acid hydrazide, hydroxylamine, p-nitrobenzoic acid, sodium chloride, thiacetazone, picrate, and oleate; catalase activity; Tween hydrolysis; urease activity; niacin detection; and nitrate reductase, acid phosphatase, arylsulfatase, pyrazinamidase, and alpha-esterase activities. In addition, a mycolic acid profile should be determined, and DNA-DNA hybridization experiments in which the difference between the denaturation temperature of the homologous reaction and the denaturation temperature of the heterologous reaction is determined should be performed. This proposal has been endorsed by the members of the Subcommittee for Taxonomy of the Mycobacteria of the International Committee on Systematic Bacteriology.

Base Composition↗

Mycobacterium hiberniae sp. nov.

Strains of a new type of slowly growing scotochromogenic, rose-pink-pigmented mycobacterium were isolated repeatedly from sphagnum vegetation, true moss, and soil in Ireland. These strains grew at 22, 31, and 37 degrees C but not at 45 degrees C and possessed acid phosphatase and arylsulfatase activities. They reduced nitrate, tolerated 0.1% NaNO2, did not split amides, and were resistant to most of the antituberculous drugs tested, except ethambutol. They did not form acid from glucose and mannose. Their internal phenetic similarity was 97.08% +/- 2.07%. The whole mycolate pattern confirmed the homogeneity of the taxa sharing similar mycolate types with several other mycobacterial species. However, on the basis of the nature of the major pyrolysis esters, the taxon appeared unique. The phylogenetic analysis based on evolutionary distance values revealed that the strains belong to a new species of slowly growing mycobacteria. The DNA-DNA hybridization values confirmed that these strains differ significantly from Mycobacterium nonchromogenicum, M. terrae, M. triviale, and M. thermoresistibile. The strains produced a unique rose-pink pigment and were nonpathogenic for mice, guinea pigs, and rabbits, but they provoked a nonspecific hypersensitivity reaction to bovine tuberculin in guinea pigs and cattle. Hence, they are considered a member of a new species of nonpathogenic slowly growing mycobacteria, for which the name Mycobacterium hiberniae is proposed. Strain Hi 11 is the type strain, a culture of which has been deposited in the American Type Culture Collection as strain ATCC 49874.

Bacterial Typing Techniques↗

Paenibacillus (formerly Bacillus) gordonae (Pichinoty et al. 1986) Ash et al. 1994 is a later subjective synonym of Paenibacillus (formerly Bacillus) validus (Nakamura 1984) Ash et al. 1994: emended description of P. validus.

A polyphasic study in which we performed an amplified ribosomal DNA restriction analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins, a gas chromatographic analysis of methylated fatty acids, pyrolysis mass spectrometry, a random amplified polymorphic DNA analysis, a phenotypic analysis, and an analysis of the levels of DNA binding of Paenibacillus gordonae and Paenibacillus validus strains (including both type strains) showed that these organisms form a homogeneous group and that the names P. gordonae and P. validus are therefore synonyms. P. validus has nomenclatural priority, and an emended description of this species is given; the type strain is strain LMG 11161 (= ATCC 43897).

Bacillus↗

Reclassification of Paenibacillus (formerly Bacillus) pulvifaciens (Nakamura 1984) Ash et al. 1994, a later subjective synonym of Paenibacillus (formerly Bacillus) larvae (White 1906) Ash et al. 1994, as a subspecies of P. larvae, with emended descriptions of P. larvae as P. larvae subsp. larvae and P. larvae subsp. pulvifaciens.

A polyphasic taxonomic study of four strains of Paenibacillus larvae and four strains of Paenibacillus pulvifaciens (including duplicates of both type strains) supported the reclassification of both former Bacillus species into one species, P. larvae. Our conclusions were based on morphological and Analytab Products (API) tests, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of whole-cell proteins, gas chromatography of methylated fatty acids, pyrolysis mass spectrometry, DNA-DNA binding, and the following genomic fingerprinting methods: amplified ribosomal DNA restriction analysis, random amplified polymorphic DNA analysis, and AFLP analysis. The last method is a novel high-resolution DNA fingerprinting technique based on the selective amplification of restriction fragments. Despite more than 90% DNA relatedness between the strains studied, SDS-PAGE of whole-cell proteins, biochemical tests, and DNA fingerprinting (AFLP) distinguished between the P. larvae and P. pulvifaciens strains at the subspecies level. Taking this evidence along with differences in pathogenicity, we propose to reclassify the honeybee pathogens P. larvae and P. pulvifaciens as P. larvae subsp. larvae and P. larvae subsp. pulvifaciens. An emended description of the species and descriptions of the subspecies are given. The type strains are P. larvae subsp. larvae ATCC 9545 (LMG 9820) and P. larvae subsp. pulvifaciens NRRL B-3685 (LMG 6911 and ATCC 13537).

Bacillus↗

Bacillus sporothermodurans, a new species producing highly heat-resistant endospores.

Bacteria that differentiate into highly heat-resistant endospores (HHRS strains) may survive ultrahigh-temperature treatment of milk and germinate in the final product. They do not noticeably spoil the milk and are nonpathogenic. The complete (>96%) 16S rRNA genes from three HHRS strains were identical, and phylogenetic analysis placed them alongside Bacillus firmus in the B. megaterium group of the genus Bacillus. Moreover, the approximately 550 nucleotides between regions U2 and U5 were invariant for seven HHRS strains. However, three cloned 16S rRNA genes from one HHRS strain, M215, showed marked size and sequence variations within the V1 and V2 regions. DNA reassociation assays confirmed the distinction between a reference HHRS strain and closely related members of the B. megaterium group, notably, B. firmus (30%), B. benzoevorans (28%), and B. circulans (20%). Ribotyping and pyrolysis mass spectrometry both indicated that the HHRS strains belong to a homogeneous, species-ranked taxon, an exception being strain TP1248, which is slightly atypical. The HHRS strains are unusual in that they grow poorly, if at all, on nutrient agar; good growth is obtained on brain heart infusion agar. On subculture, most HHRS strains form long, filamentous rods which stain unevenly in the Gram reaction. They are strictly aerobic and do not produce acid from sugars. We propose the name Bacillus sporothermodurans for these bacteria, which are phenotypically and phylogenetically distinct from other Bacillus species. The type strain is M215 (= DSMZ 10599).

Animals↗

A polyphasic reassessment of the genus Paenibacillus, reclassification of Bacillus lautus (Nakamura 1984) as Paenibacillus lautus comb. nov. and of Bacillus peoriae (Montefusco et al. 1993) as Paenibacillus peoriae comb. nov., and emended descriptions of P. lautus and of P. peoriae.

Seventy-seven strains representing 10 species in the Paenibacillus polymyxa 16S rRNA group and 3 other species that exhibit phenetic relatedness to members of this group, Bacillus lautus, "Bacillus longisporus," and Bacillus peoriae, were characterized genotypically and phenotypically by performing an amplified ribosomal DNA restriction analysis, a randomly amplified polymorphic DNA analysis, a fatty acid methyl ester analysis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins, pyrolysis mass spectrometry, and API and other routine phenotypic tests. These analyses revealed distinct clusters representing Paenibacillus alvei, Paenibacillus amylolyticus, Paenibacillus azotofixans, Paenibacillus durum, Paenibacillus larvae subsp. larvae, Paenibacillus larvae subsp. pulvifaciens, B. lautus, Paenibacillus macerans, Paenibacillus macquariensis, B. peoriae, P. polymyxa, and Paenibacillus validus, which confirmed the distinctness of these species, but appreciable within-species heterogeneity was observed in P. alvei, B. lautus, P. macerans, P. polymyxa, and P. validus. The type strain of Paenibacillus pabuli did not cluster with other strains of this species, and in several analyses a relationship between strains of P. pabuli and "B. longisporus" was observed. As the analyses showed that B. lautus and B. peoriae are closely related to the genus Paenibacillus, these species are reclassified as members of this genus.

Bacillus↗

Characterization of smooth and rough morphotypes of Peptostreptococcus micros.

Isolation of the smooth (Sm) morphotype of Peptostreptococcus micros, a suspected oral pathogen, is sometimes accompanied by isolation of a rough (Rg) morphotype of P. micros. The Rg type readily changes to a Sm-like variant (RgSm) in broth culture. Sm and Rg isolates and RgSm variants were compared to determine whether these three types are the result of phase variation. The RgSm variants resembled the Sm morphotype in colony morphology; furthermore, the Sm type and the RgSm type did not have the fibrillar surface structures characteristic of the Rg type, and the Sm and RgSm types were more hydrophobic than the Rg type. However, when we compared the sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of whole-cell proteins, serotyping data, pyrolysis mass spectrometry data, 16S ribosomal DNA sequences, and hemolytic activities, the RgSm variants and the Rg isolates were very similar and were clearly distinct from the Sm isolates. These results suggest that the Rg and RgSm types form a cluster distinct from the Sm type and thus provide evidence that P. micros can be differentiated into two groups, one consisting of the Sm type and the other consisting of the Rg and RgSm types.

Base Sequence↗

Rapid identification of urinary tract infection bacteria using hyperspectral whole-organism fingerprinting and artificial neural networks.

Three rapid spectroscopic approaches for whole-organism fingerprinting-pyrolysis mass spectrometry (PyMS), Fourier transform infra-red spectroscopy (FT-IR) and dispersive Raman microscopy--were used to analyse a group of 59 clinical bacterial isolates associated with urinary tract infection. Direct visual analysis of these spectra was not possible, highlighting the need to use methods to reduce the dimensionality of these hyperspectral data. The unsupervised methods of discriminant function and hierarchical cluster analyses were employed to group these organisms based on their spectral fingerprints, but none produced wholly satisfactory groupings which were characteristic for each of the five bacterial types. In contrast, for PyMS and FT-IR, the artificial neural network (ANN) approaches exploiting multi-layer perceptrons or radial basis functions could be trained with representative spectra of the five bacterial groups so that isolates from clinical bacteriuria in an independent unseen test set could be correctly identified. Comparable ANNs trained with Raman spectra correctly identified some 80% of the same test set. PyMS and FT-IR have often been exploited within microbial systematics, but these are believed to be the first published data showing the ability of dispersive Raman microscopy to discriminate clinically significant intact bacterial species. These results demonstrate that modern analytical spectroscopies of high intrinsic dimensionality can provide rapid accurate microbial characterization techniques, but only when combined with appropriate chemometrics.

Bacterial Typing Techniques↗

Polycations increase the permeability of Mycobacterium vaccae cell envelopes to hydrophobic compounds.

Polycations [protamine, polymyxin B nonapeptide (PMBN) and polyethyleneimine (PEI)] have been shown to increase the cell wall permeability of Mycobacterium vaccae to highly hydrophobic compounds, as manifested in enhanced intracellular bioconversion of beta-sitosterol to 4-androsten-3,17-dione (AD) and 1,4-androstadien-3,17-dione (ADD), and cell sensitization to erythromycin and rifampicin. The quantity of AD(D) formed per biomass unit was twice as high in the presence of PMBN and PEI, and three times higher with protamine. The sensitization factor, i.e. the MIC(50) ratio of the control bacteria to those exposed to polycations, ranged from 4 to 16, depending on the polycation/antibiotic combination. Non-covalently bound free lipids were extracted from the control and polycation-treated cells and fractionated with the use of chloroform, acetone and methanol. Chloroform- and acetone-eluted fractions (mainly neutral lipids and glycolipids, respectively) showed significant polycation-induced alterations in their quantitative and qualitative composition. The fatty acid profile of neutral lipids was reduced in comparison to control, whereas acetone-derived lipids were characterized by a much higher level of octadecenoic acid (C(18:1)) and a considerably lower content of docosanoic acid (C(22:0)), the marker compound of mycolate-containing glycolipids. Methanol-eluted fractions remained unaltered. Cell-wall-linked mycolates obtained from delipidated cells were apparently unaffected by the action of polycations, as judged from the TLC pattern of mycolic acid subclasses, the mean weight of mycolate preparations and the C(22:0) acid content in the mycolates, determined by GC/MS and pyrolysis GC. The results suggest the involvement of the components of non-covalently bound lipids in the outer layer in the M. vaccae permeability barrier.

Anti-Bacterial Agents↗

Identification of novel sulfur-containing bacterial polyesters: biosynthesis of poly(3-hydroxy-S-propyl-omega-thioalkanoates) containing thioether linkages in the side chains.

This study describes the biosynthesis of novel sulfur-containing polyhydroxyalkanoates (PHAs), which consist exclusively of hydroxypropylthioalkanoic acid containing thioether groups in the side chains. In addition, the utilization of alkylthioalkanoic acids (=thia fatty acids) by various bacteria was investigated. Based on feedings with propylthiooctanoic acid (PTO) or propylthiohexanoic acid, the metabolically engineered PHA-negative mutant PHB(-)4 of Ralstonia eutropha, which harbours plasmid pBBR1::phaC1 expressing the PHA synthase of Pseudomonas mendocina, synthesized two novel poly(3-hydroxy-S-propyl-omega-thioalkanoic) acids [poly(3HPTA)s]. A terpolyester consisting of 3-hydroxypropylthiobutyric acid (3HPTB), 3-hydroxypropylthiohexanoic acid (3HPTHx) and 3-hydroxypropyl- thiooctanoic acid (3HPTO) was synthesized from PTO, whereas a co-polyester of 3HPTB and 3HPTHx was synthesized from propylthiohexanoic acid. Fed-batch fermentation of R. eutropha PHB(-)4(pBBR1::phaC1) on PTO was done on a 26-litre scale, providing a cell density of 7.3 g l(-1), from which 45 g of the novel poly(3HPTB-co-3HPTHx-co-3HPTO) were isolated. The chemical structures of the poly(3HPTA)s were identified by gas chromatography/mass spectrometry, elemental sulfur analysis, partial pyrolysis and detailed mass spectrometric analysis, exhibiting 3HPTB, 3HPTHx and 3HPTO as constituents. These novel, hitherto undescribed, constituents of PHAs were randomly distributed in the co-polyesters.

Acyltransferases↗

Location of functional groups in mycobacterial meromycolate chains; the recognition of new structural principles in mycolic acids.

Mycobacterial alpha-, methoxy- and keto-mycolic acid methyl esters were separated by argentation chromatography into mycolates with no double bond, with one trans double bond or with one cis double bond. Meromycolic acids were prepared from each methyl mycolate fraction by pyrolysis, followed by silver oxide oxidation, and analysed by high-energy collision-induced dissociation/fast atom bombardment MS to reveal the exact locations of the functional groups within the meromycolate chain. The locations of cis and trans double bonds, cis and trans cyclopropane rings, methoxy and keto groups, and methyl branches within the meromycolate chain were determined from their characteristic fragment ion profiles, and the structures of the meromycolic acids, including those with three functional groups extracted from Mycobacterium tuberculosis H37Ra, Mycobacterium bovis BCG and Mycobacterium microti, were established. Meromycolic acids with one cis double bond were structurally closely related to those with one cis cyclopropane ring, whereas the meromycolic acids with one trans cyclopropane ring were closely related to the corresponding meromycolic acids with one cis cyclopropane ring. A close relationship between methoxy- and keto-meromycolic acids was also implied. The relationship between the meromycolic acids with a trans double bond and the other meromycolic acids was not clearly revealed, and they did not appear to be immediate substrates for trans cyclopropanation.

Hydrogen↗

A comparison of Bacteroides ureolyticus isolates from different clinical sources.

Clinical isolates of corroding, gram-negative, anaerobic bacilli (provisionally identified as Bacteroides ureolyticus) from superficial ulcers and soft tissue infections (15), non-gonococcal, non-chlamydial urethritis (12) and adult periodontal disease (14) were compared with reference strains of B. ureolyticus, B. gracilis and Wolinella recta in a series of conventional tests of morphology, biochemical activity, tolerance of dyes and bile salts, and antibiotic sensitivity, gas-liquid chromatographic analysis of metabolic products, and in whole-cell analysis by pyrolysis-mass spectrometry (Py-MS). A numerical taxonomic approach was used with the results of conventional tests and the grouping obtained was compared with that obtained by Py-MS. All the ulcer and soft-tissue isolates and the urethritis isolates were oxidase- and urease-positive and formed a homogeneous set consistent with the reference strain of B. ureolyticus. The dental isolates differed from B. ureolyticus strains and were heterogeneous amongst themselves. None corresponded with the reference strains of B. gracilis or W. recta. The conventional and Py-MS approaches to characterisation produced similar groupings and each distinguished between a single cluster of ulcer-urethritis strains and several clusters of dental strains, although the dendrograms derived from the two approaches differed in the order of the clusters; in the Py-MS dendrogram one subcluster of four dental strains came within the main ulcer-urethritis cluster and a cluster of five ulcer strains was separated as a distinct group.

Bacteroides↗

Heterogeneity within apparently pure cultures of Escherichia coli freshly isolated from significant bacteriuria.

Pyrolysis mass spectrometry (PyMS), a highly discriminatory method for comparison of isolates, was used to assess the homogeneity of colonies taken from apparently pure cultures of Escherichia coli in 10 urine specimens. Ten randomly selected colonies were subcultured from each urine for comparison. For six urines, the set of 10 single-colony isolates proved indistinguishable by PyMS. However, for four urines there was clear heterogeneity. For two urines, one of the isolates was distinct, and the remaining nine indistinguishable. One urine yielded seven indistinguishable isolates, and three further individually distinct isolates. One urine yielded two clusters of indistinguishable isolates, one comprising seven and the other three isolates. Thus, significant heterogeneity (as measured by PyMS) occurs in apparently pure cultures of E. coli from urinary tract infection. The nature of this heterogeneity remains to be established, as does the significance, if any, of this phenomenon in urinary tract infection.

Bacteriuria↗

Phenotypic and genotypic diversity of fluorescent pseudomonads isolated from field-grown sugar beet.

A sample of 30 fluorescent pseudomonads isolated from the phyllosphere of sugar beet throughout a single growing season and shown to be closely related on the basis of fatty acid methyl ester (FAME) analysis was subjected to detailed phenotypic and genotypic characterization. Phenotypic traits were assessed on the basis of biochemical properties, assimilation of sole carbon sources, FAME analysis, organic pyrolysate content (MS-pyrolysis), and total cellular protein profiles. With the exception of total cellular protein profiles, numerical analysis of the data revealed two main clusters, each of which was divided into several subclusters. Numerical analysis of total cellular protein data failed to differentiate isolates into two main clusters, but nevertheless grouped isolates into six subclusters. On the basis of biochemical and carbon source assimilation profiles, 19 isolates were identified as Pseudomonas fluorescens biovar V, eight isolates as P. fluorescens biovar III and three isolates as P. syringae pathovar syringae. In general, all methods of phenotypic analysis grouped isolates according to time of sampling and leaf type. Genome analysis was undertaken by pulsed-field gel electrophoresis (PFGE) of PacI, SpeI, SwaI and XbaI macrorestriction fragments and revealed the presence of eight distinct genomic (clonal) groups. These groups correlated closely with the clusters generated by numerical analysis of phenotypic data, but there was no correlation between macrorestriction fragment profile and isolate identification; in fact the variation in macrorestriction fragment patterns within P. fluorescens biovars was as great as the variation detected between biovars, and between P. fluorescens and P. syringae. Statistical evaluation of macrorestriction fragment patterns revealed two examples of recent strain divergence: one was due to the presence of a 400 kbp plasmid within one isolate of a collection of nine otherwise genomically identical isolates, and the other was observed between two phenotypically similar isolates sampled 220 d apart. Genetic variation was expressed in terms of nucleotide diversity (pi) and pairwise comparisons yielded values ranging from 0.0029 to 0.1517. The mean intrapopulation genetic variation was high (0.0993), but limited genetic variation was detected among isolates sampled on each occasion. Taken together this suggests a population comprised of a variety of apparently distantly related clones (genomic groups), each adapted to local conditions. Genome sizes were estimated from the sum of SpeI restriction fragments and ranged from 4.2 to 5.5 Mbp. Examination of the distribution of XbaI, SpeI, SwaI and PacI restriction endonuclease sites showed that the distribution of SpeI sites differed significantly from the expected (random) distribution.

Bacterial Proteins↗

Williamsia deligens sp. nov., isolated from human blood.

The taxonomic status of two bacterial strains isolated from human blood was characterized using a polyphasic approach. Chemotaxonomic investigations revealed the presence of cell-wall chemotype IV, short-chain mycolic acids that co-migrated with those extracted from members of the genus Williamsia and that produce C(16 : 0) and C(18 : 0) fatty acids on pyrolysis GC, and dihydrogenated menaquinone with nine isoprene units as the predominant isoprenologue. The generic assignment was confirmed by 16S rRNA gene sequencing. Comparative analysis of the 16S rRNA gene sequence showed that these isolates constitute a distinct phyletic line within the genus Williamsia, displaying 96.2 and 97.2 % sequence similarities to Williamsia muralis and Williamsia maris, respectively. The two isolates could be distinguished from the type strains of the latter species on the basis of several phenotypic traits. The genotypic and phenotypic data show that the strains merit classification as a novel species of Williamsia, for which the name Williamsia deligens sp. nov. is proposed, with type strain IMMIB RIV-956T (= DSM 44902T = CCUG 50873T).

Actinomycetales↗

Gordonia defluvii sp. nov., an actinomycete isolated from activated sludge foam.

Three strains of non-motile, Gram-positive, filamentous actinomycetes, isolates J4(T), J5 and J59, initially recognized microscopically in activated sludge foam by their distinctive branching patterns, were isolated by micromanipulation. The taxonomic positions of the isolates were determined using a polyphasic approach. Almost-complete 16S rRNA gene sequences of the isolates were aligned with corresponding sequences of representatives of the suborder Corynebacterineae and phylogenetic trees were inferred using three tree-making algorithms. The organisms formed a distinct phyletic line in the Gordonia 16S rRNA gene tree. The three isolates showed 16S rRNA gene sequence similarities within the range 96.9-97.2 % with their nearest phylogenetic neighbours, namely Gordonia bronchialis DSM 43247(T) and Gordonia terrae DSM 43249(T). Strain J4(T) was shown to have a chemotaxonomic profile typical of the genus Gordonia and was readily distinguished from representatives of the genus on the basis of Curie-point pyrolysis mass spectrometric data. The isolates shared nearly identical phenotypic profiles that distinguished them from representatives of the most closely related Gordonia species. It is evident from the genotypic and phenotypic data that the three isolates belong to a novel Gordonia species. The name proposed for this taxon is Gordonia defluvii sp. nov.; the type strain is J4(T) (=DSM 44981(T)=NCIMB 14149(T)).

Bacterial Typing Techniques↗