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Peter Schumann

Publications and source records attributed to Peter Schumann.

107 records · Page 6Linked to original sources

Knoellia sinensis gen. nov., sp. nov. and Knoellia subterranea sp. nov., two novel actinobacteria isolated from a cave.

Two novel strains of the class Actinobacteria were isolated from a cave in China. Cells of both strains were gram-positive, non-motile, non-spore-forming and not acid-fast and exhibited a rod/coccus growth cycle. Both isolates grew well on complex organic media under aerobic conditions. Their cell wall peptidoglycan contained meso-diaminopimelic acid as diagnostic diamino acid. The acyl type of the glycan chain of peptidoglycan was acetyl. The major respiratory quinone was MK-8(H4). The cellular fatty acid profile was characterized by the predominance of 13-methyltetradecanoic (i-C15:0), 15-methylhexadecanoic (i-C17:0), 14-methylpentadecanoic (i-C16:0) and 14-methylhexadecanoic (ai-C17:0) acids. The major polar lipids were phosphatidylethanolamine, phosphatidylinositol and diphosphatidylglycerol. Mycolic acids were absent. The DNA G+C composition was 68-69 mol%. 16S rDNA-based phylogenetic analysis revealed an intermediate phylogenetic position of the cave isolates between the genera Janibacter and Tetrasphaera, which did not permit their unambiguous affiliation to either genus. Differences in morphological, physiological and chemotaxonomic properties between the two isolates and their closest phylogenetic neighbours support the proposal of a new genus and two novel species, Knoellia sinensis gen. nov., sp. nov. and Knoellia subterranea sp. nov. The type and only strains of the species are respectively HKI 0119T (= DSM 12331T = CIP 106775T) and HKI 0120T (= DSM 12332T = CIP 106776T).

Actinobacteria↗

Emended descriptions of the genus Micrococcus, Micrococcus luteus (Cohn 1872) and Micrococcus lylae (Kloos et al. 1974).

Nine yellow-pigmented, spherical bacterial strains isolated from a medieval wall painting (strain D7), from indoor air (strains 3, 6, 7, 13C2, 38, 83 and 118) and from an activated-sludge plant (strain Ballarat) were classified by a polyphasic approach. Analyses of the 16S rRNA gene sequences of three representatives (strains D7, 118 and Ballarat) indicated that they all belong to the genus Micrococcus. The three isolates shared the highest sequence similarities with Micrococcus luteus DSM 20030T (97.9-98%), Micrococcus antarcticus AS 1.2372T (97.9-98.3%) and Micrococcus lylae DSM 20315T (97.5-97.9%). DNA-DNA reassociation studies clearly demonstrated that all nine isolates belong to the species M. luteus. However, neither their chemotaxonomic features nor their physiological and biochemical properties were consistent with those of M. luteus DSM 20030T. In contrast to M. luteus DSM 20030T, all isolates investigated possessed MK-8(H2) as the major respiratory quinone, and strain Ballarat had an A4alpha peptidoglycan type. On the basis of analyses of their Fourier transform-infrared spectroscopy spectra, isolates D7, 3, 6, 7, 13C2, 38, 83 and 118 could be grouped into a single cluster separate from M. luteus DSM 20030T, strain Ballarat and M. lylae DSM 20315T. In addition, all these isolates could be distinguished from M. luteus DSM 20030T by their ability to assimilate D-maltose, D-trehalose, DL-3-hydroxybutyrate, DL-lactate, pyruvate and L-histidine and to hydrolyse casein. Strains D7, 3, 6, 7, 13C2, 38, 83 and 118 differed from both M. luteus DSM 20030T and strain Ballarat by their ability to assimilate acetate, L-phenylalanine, L-serine and phenylacetate. Furthermore, REP-PCR fingerprinting yielded one common band for these strains, whereas this band was not observed for M. luteus DSM 20030T, strain Ballarat or M. lylae DSM 20315T. On the basis of these data, the species M. luteus can be divided into three biovars that are distinguished by several chemotaxonomic and biochemical traits: biovar I, represented by M. luteus DSM 20030T; biovar II, represented by strains D7 (= DSM 14234 = CCM 4959), 3, 6, 7, 13C2, 38, 83 and 118; and biovar III, represented by strain Ballarat (= DSM 14235 = CCM 4960). On the basis of the results generated in this study, emended descriptions of the genus Micrococcus and the species M. luteus and M. lylae are given.

Air Microbiology↗

Leuconostoc ficulneum sp. nov., a novel lactic acid bacterium isolated from a ripe fig, and reclassification of Lactobacillus fructosus as Leuconostoc fructosum comb. nov.

An isolate, designated strain FS-1T, was recovered from a ripe fig. Phylogenetic analysis of the 16S rRNA genes and DNA-DNA reassociation values showed that the organism represented a novel species of the genus Leuconostoc closely related to Lactobacillus fructosus. The novel isolate could be distinguished from the type strain of Lactobacillus fructosus by the fatty acid composition and several phenotypic and growth characteristics. In strain FS-1T, 18:1 delta9 (18:1omega9c) was present in relatively large amounts whilst, in Lactobacillus fructosus, this fatty acid was a minor component. Strain FS-1T and Lactobacillus fructosus produced acid in API 50CHL microtubes from glucose, fructose and mannitol within 48 h, whereas only strain FS-1T also fermented trehalose, gluconate, turanose and sucrose after 48 h. Other differences in acid production from carbohydrates also distinguished strain FS-1T from Lactobacillus fructosus. Both organisms were heterofermentative with fructose as a substrate and fermented glucose only in the presence of fructose, as determined by nuclear magnetic resonance studies. Strain FS-1T was catalase-positive. On the basis of the phylogenetic analysis, DNA-DNA reassociation values, physiological and biochemical characteristics and fatty acid composition, the name Leuconostoc ficulneum is proposed for the novel species represented by strain FS-1T, and it is proposed that Lactobacillus fructosus be reclassified in the genus Leuconostoc as Leuconostoc fructosum comb. nov.

Carbohydrate Metabolism↗

Georgenia muralis gen. nov., sp. nov., a novel actinobacterium isolated from a medieval wall painting.

Two bacterial strains, designated 1A-C(T) and 3A-1, were studied and, using these results and previously published data, taxonomically classified. Cells of the strains exhibited a rod-coccus cycle. The peptidoglycan determined for 1A-C(T) was of type A4alpha with lysine as the diagnostic cell-wall diamino acid and an interpeptide bridge of L-Lys <-- L-Glu. The menaquinone systems of the two strains contained MK-8(H4) (82-94%) and MK-7(H4) (3-11%). The polar lipid profiles consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol mannoside, two unidentified phospholipids and an unidentified glycolipid. The fatty acid profiles contained predominantly ai-C15:0 and significant amounts of i-C14:0 and i-C15:1 fatty acids. Genomic fingerprints clearly distinguished strains 1A-C(T) and 3A-1 from each other. DNA-DNA relatedness between the two strains (92%) demonstrated that they are members of a single species. Analyses of the 16S rDNA sequences of strains IA-C(T) and 3A-1, which were almost identical (99.6% sequence similarity), and comparison with corresponding sequences demonstrated that they represent a novel lineage within the suborder Micrococcineae, most closely related to species of the genera Beutenbergia, Bogoriella and Cellulomonas (94.7-95.7% sequence similarity). The results demonstrate that the two strains are members of a single new genus and a single novel species. Thus, the name Georgenia muralis gen. nov., sp. nov. is proposed. The type strain is strain 1A-C(T) (= DSM 14418T = CCM 4963T). Another strain of the species is strain 3A-1 (= DSM 14419 = CCM 4964).

Actinomycetales↗

Re-evaluation of the status of the genus Oerskovia, reclassification of Promicromonospora enterophila (Jáger et al. 1983) as Oerskovia enterophila comb. nov. and description of Oerskovia jenensis sp. nov. and Oerskovia paurometabola sp. nov.

Phylogenetic analysis of Promicromonospora enterophila indicates that this taxon clusters with Cellulomonas species, adjacent to Cellulomonas turbata (basonym Oerskovia turbata). 16S rDNA analysis, DNA-DNA reassociation, riboprinting, peptidoglycan analysis and determination of phenotypic properties of various strains of P. enterophila and C turbata reveal that they form a cluster that can be distinguished unambiguously from other Cellulomonas species by morphology, amino acid composition of the cell wall and 16S rDNA signatures. As a result of thispolyphasic study, it appears taxonomically reasonable to re-establish the genus Oerskovia for C turbata and to reclassify P. enterophila as Oerskovia enterophila comb. nov.; two novel species, Oerskovia jenensis sp. nov. (type strain DSM 46000T = CIP 100330T) and Oerskovia paurometabola sp. nov. (type strain DSM 14281T = LMG 20385T), are also proposed.

Actinomycetales↗

Emended description of the genus Trichococcus, description of Trichococcus collinsii sp. nov., and reclassification of Lactosphaera pasteurii as Trichococcus pasteurii comb. nov. and of Ruminococcus palustris as Trichococcus palustris comb. nov. in the low-G+C gram-positive bacteria.

Analyses of 165 rRNA gene sequences, restriction endonuclease digestion fingerprints of 16S-23S intergenic regions, DNA base compositions, fatty-acid profiles, cell-wall chemistry, cell physiology and fermentation end-product composition, along with other biochemical and phenotypic properties, supported the view that Trichococcus flocculiformis EchtT (DSM 2094T), Lactosphaera pasteurii KoTa2T (DSM 2381T), Ruminococcus palustris Z-7189T (DSM 9172T) and an isolate named 'Carnococcus allantoicus' NDP were all very similar and should be merged into a single genus. Detailed characterization of strains Ben 77, Ben 200 and Ben 201 described previously as 'Nostocoida limicola' I, a filamentous bacterium which causes bulking in activated sludge systems, revealed that these strains also belonged to the same genus as T. flocculiformis EchtT, L. pasteurii KoTa2T, R. palustris Z-7189T and 'C allantoicus' NDP. In fact, their shared properties suggested that these strains all belonged to a single species. However, DNA-DNA hybridization data indicated that T. flocculiformis EchtT, all of the 'N. limicola' I isolates and 'C allantoicus' NDP belonged to the same species, whereas L. pasteurii KoTa2T, R. palustris Z-7189T and two new isolates, 37AN3*T and 45AN2, represented three distinct species within the same genus. The priority of the genus name Trichococcus is established and since its validation predates the description of the genus Lactosphaera this name should take precedence. Under certain culture conditions, all of the strains mentioned above could produce chains of cocci. Furthermore, the morphology of T. flocculiformis EchtT could change to a non-filamentous form on certain media. This study proposes that the above strains be reclassified as members of the genus Trichococcus as four species, namely Trichococcus flocculiformis emend. (type strain EchtT = DSM 2094T), Trichococcus pasteurii comb. nov. (type strain KoTa2T = DSM 2381T = ATCC 35945T), Trichococcus collinsii sp. nov. (type strain 37AN3*T = DSM 14526T = ATCC BAA-296T, and Trichococcus palustris comb. nov. (type strain Z-7189T = DSM 9172T).

Bacteria↗

Exiguobacterium undae sp. nov. and Exiguobacterium antarcticum sp. nov.

Four orange-pigmented strains from pond water (L1-L4) have been subjected to polyphasic taxonomic analyses. On the basis of ribotype analysis and Fourier-transform infrared spectroscopy, these strains form a genomically highly related group. 16S rDNA sequence analysis revealed 98.8% similarity between the 16S rDNA sequences of strains L2T and H2T, isolated previously from a microbial mat from Lake Fryxell, Antarctica. DNA-DNA reassociation values indicated the presence of two genomic clusters. While the DNA of strains L2T and L3 showed 100% DNA relatedness, strains L2T and H2T shared only 51% DNA relatedness. These two clusters differed in some phenotypic properties, e.g. utilization of melibiose, D-mannitol, adenosine 5'-monophosphate and uridine 5'-monophosphate, and in their fatty acid compositions. Based on the composition of isoprenoid quinones, peptidoglycan, polar lipids and fatty acids, these organisms are members of the genus Exiguobacterium. This is supported by 16S rDNA analyses, which revealed 97-98% similarity to Exiguobacterium acetylicum DSM 20416T and 93.2-93.8% similarity to Exiguobacterium aurantiacum DSM 6208T. E. acetylicum DSM 20416T, the closest phylogenetic neighbour, shows only 39% DNA similarity to strain L2T and 40% DNA similarity to strain H2T. Based on genomic distinctiveness and the clear differences in chemotaxonomy and physiology, two novel species are proposed, Exiguobacterium undae sp. nov. and Exiguobacterium antarcticum sp. nov.

Bacillaceae↗

Agrococcus baldri sp. nov., isolated from the air in the 'Virgilkapelle' in Vienna.

Five coccoid, Gram-positive strains were isolated from the air of the 'Virgilkapelle' in Vienna. A representative of these five strains, V-108T, shared 99.0 and 98.4% 16S rDNA sequence similarity, respectively, with Agrococcus jenensis DSM 9580 and Agrococcus citreus DSM 12453T. Colonies of the five strains were white when grown in the dark and turned yellow in the light. The strains displayed highly similar biochemical and physiological characteristics and showed only small differences in their protein patterns obtained after SDS-PAGE. Based on Fourier-transform infra-red (FT-IR) spectra, the five strains were grouped together and separated from the other members of the genus, A. jenensis and A. citreus. Chemotaxonomic characteristics analysed from selected members of the five isolates, including polar lipids, quinone systems, polyamine patterns, cell wall composition and fatty acid profiles, were in good agreement with those of the two species of the genus Agrococcus described to date. The G+C content of the genomic DNA was determined to be within the narrow range of 73.8-74.9 mol%. The results of DNA-DNA hybridization with A. citreus DSM 12453T and A. jenensis DSM 9580T, as well as differences in biochemical/physiological characteristics, peptidoglycan composition, fatty acids, polar lipid profiles and FT-IR spectra, demonstrated that the five isolates represent a novel species of the genus Agrococcus. The name Agrococcus baldri sp. nov. is proposed for the novel species, of which strain V-108T (= DSM 14215T = CCM 4953T) is the type strain.

Actinomycetales↗

Microbacterium aerolatum sp. nov., isolated from the air in the 'Virgilkapelle' in Vienna.

Three rod-shaped, Gram-positive strains were isolated from the air of the chapel 'Virgilkapelle' in Vienna. A representative of these three strains, strain V-73T, shared the highest 16S rDNA sequence similarities with members of the genus Microbacterium, in particular Microbacterium foliorum, Microbacterium testaceum, Microbacterium esteraromaticum, Microbacterium keratanolyticum and Microbacterium arabinogalactanolyticum. The strains displayed almost identical biochemical and physiological characteristics and showed no differences in their protein patterns obtained after SDS-PAGE. On the basis of Fourier-transform infra-red (FT-IR) spectra and genomic fingerprints, the three strains were grouped together and separated from the other relevant members of the genus Microbacterium. The chemotaxonomic characteristics analysed, including polar lipids, quinone systems, cell wall composition and fatty acid profiles, were in good agreement with the characteristics described for the genus Microbacterium. The G+C content of the DNAs was determined to be in the narrow range 69.3-69.7 mol %. The results of DNA-DNA hybridization, biochemical/physiological characterization, ERIC-PCR-generated genomic fingerprints and FT-IR spectra demonstrated that the three isolates represent a novel species of the genus Microbacterium. The name Microbacterium aerolatum sp. nov. is proposed for the novel species, of which strain V-73T (= DSM 14217T = CCM 4955T) is the type strain.

Actinomycetales↗

Psychrobacter submarinus sp. nov. and Psychrobacter marincola sp. nov., psychrophilic halophiles from marine environments.

Two novel psychrophilic, halophilic, Psychrobacter-like bacteria, strains KMM 225T and KMM 277T, were isolated from sea water and the internal tissues of an ascidian Polysyncraton sp. specimen, respectively, and characterized using a polyphasic approach, which included phenotypic, genotypic, chemotaxonomic and phylogenetic analyses. The novel marine isolates were Gram-negative, aerobic, coccoid, oxidase- and catalase-positive, non-pigmented, non-motile, psychrophilic and halophilic and they utilized a restricted spectrum of carbon sources. Strains KMM 225T and KMM 277T required sea water or sodium ions for growth and were tolerant of up to 12-15% (w/v) NaCl. Growth of strains KMM 225T and KMM 277T was observed at 4-35 and 7-35 degrees C, respectively. The DNA G+C contents of KMM 225T and KMM 277T were respectively 46-8 and 50.7 mol %. Comparison of almost complete 16S rDNA sequences of strains KMM 225T and KMM 277T revealed that both strains were phylogenetically most closely related to each other (99.9% sequence similarity) and slightly less related to Psychrobacter glacincola, with 97.2 and 97.8% similarity, respectively. DNA-DNA reassociation between KMM 225T and KMM 277T revealed 15% similarity, whereas similarity to other Psychrobacter species was 14-25%. Strains KMM 225T and KMM 277T differed from one another in their growth temperature, organic substrate utilization, antibiotic sensitivity and DNA G+C content. Both strains examined could be distinguished from all previously described Psychrobacter species by their physiological, genotypic and phylogenetic characteristics. On the basis of the physiological and molecular properties of the novel isolates, the names Psychrobacter submarinus sp. nov. (type strain KMM 225T = DSM 14161T) and Psychrobacter marincola sp. nov. (type strain KMM 277T = DSM 14160T) are proposed.

Animals↗

Diversity of grass-associated Microbacteriaceae isolated from the phyllosphere and litter layer after mulching the sward; polyphasic characterization of Subtercola pratensis sp. nov., Curtobacterium herbarum sp. nov. and Plantibacter flavus gen. nov., sp. nov.

A representative selection of coryneform bacteria, isolated from the phyllosphere of grasses and the litter layer after mulching the sward, was characterized by a polyphasic approach to clarify their taxonomic position in the family Microbacteriaceae, with particular reference to potentially plant-pathogenic bacteria. On the basis of 16S rDNA analysis, the isolates can be classified into six genotypes representing the genera Curtobacterium, Clavibacter, Subtercola and a subgroup, which was not affiliated to a known genus. One genotype, belonging to the genus Curtobacterium, had an identical 16S rDNA sequence to reference strains of the Curtobacterium flaccumfaciens pathovars. Another genotype, closely related to the potentially pathogenic Curtobacterium flaccumfaciens, could be distinguished from known species of the genus on the basis of phylogenetic and phenotypic characterization and is consequently proposed as a novel species, Curtobacterium herbarum sp. nov. (type strain P 420/07T DSM 14013T = LMG 19917T). Two genotypes assigned to Clavibacter showed a close relationship to Clavibacter michiganensis subsp. tessellarius, a pathogenic bacterium causing foliar lesions on wheat. A further genotype, which clustered clearly in the genus Subtercola by comparison of 16S rDNA sequences, showed a hitherto undescribed B-type of peptidoglycan containing the diagnostic diamino acids ornithine and 2,4-diaminobutyric acid, in the cell wall; this genotype is proposed as Subtercola pratensis sp. nov. (type strain P 229/10T = DSM 14246T = LMG 21000T). For one genotype, which formed a phylogenetically separate branch in the family of Microbacteriaceae showing chemotaxonomic similarities to the genus Rathayibacter, a novel genus, Plantibacter gen. nov., is proposed; the type species is Plantibacter flavus sp. nov. (type strain P 297/02T = DSM 14012T = LMG 19919T).

Actinomycetales↗

Kytococcus schroeteri sp. nov., a novel Gram-positive actinobacterium isolated from a human clinical source.

A strain of a gram-positive, coccoid, yellow-pigmented bacterium was isolated from human blood. The bacterium was aerobic, non-encapsulated and non-motile. Phenotypically, the bacterium closely resembled Kytococcus sedentarius, but could be distinguished from this species by physiological tests and chemotaxonomic investigations. The peptidoglycan type is L-Lys-Glu2, variation A4alpha. The predominant menaquinones are MK-8 and MK-7. The major cellular fatty acids are iso-C17:1, iso-C17:0, iso-C15:0 and anteiso-C17:0. The strain contains catalase and does not produce acid from carbohydrates. The ability to hydrolyse Tween 80 and the lack of alpha-glucosidase activity are the most characteristic features. The results of comparative 16S rDNA analysis revealed that the strain represents a novel species within the genus Kytococcus, for which the name Kytococcus schroeteri sp. nov. is proposed. The type strain is strain Muenster 2000T (= DSM 13884T = CCM 4918T).

Actinomycetales↗

Brachybacterium fresconis sp. nov. and Brachybacterium sacelli sp. nov., isolated from deteriorated parts of a medieval wall painting of the chapel of Castle Herberstein (Austria).

From two samples of microbial biofilms, damaging the mural paintings at the Saint-Catherine chapel of Castle Herberstein (Austria), four and nine coryneform bacteria were isolated, respectively. A polyphasic taxonomic study of these isolates, including morphological, biochemical and chemotaxonomic characterization, REP-PCR fingerprinting, 16S rDNA sequence analysis, DNA base ratio and DNA-DNA hybridizations, allocated them to the genus Brachybacterium. The isolates of the two samples both represent new species, for which the names Brachybacterium fresconis sp. nov. and Brachybacterium sacelli sp. nov. are proposed. The respective type strains are LMG 20336T (= DSM 14564T) and LMG 20345T (= DSM 14566T).

Actinomycetales↗

Propionimicrobium gen. nov., a new genus to accommodate Propionibacterium lymphophilum (Torrey 1916) Johnson and Cummins 1972, 1057AL as Propionimicrobium lymphophilum comb. nov.

Based upon significant differences in chemotaxonomic properties, i.e., amino acid composition of peptidoglycan, fatty acids and base composition of DNA, and supported by the phylogenetic position of the 165 rDNA sequence the species Propionibacterium lymphophilum was reclassified as Propionimicrobium lymphophilum comb. nov.

Amino Acids↗

Citricoccus muralis gen. nov., sp. nov., a novel actinobacterium isolated from a medieval wall painting.

A Gram-positive, aerobic, spherical actinobacterium, designated strain 4-0(T), was isolated from a medieval wall painting and characterized to determine its taxonomic position. The peptidoglycan of strain 4-0(T) was of type A4alpha, with lysine as the diagnostic cell wall diamino acid and an interpeptide bridge of Lys-Gly-Glu. Its quinone system contained predominantly MK-9(H2) (64%) and its polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, four unknown glycolipids, two unknown phospholipids and an unknown lipid. The fatty acid profile of strain 4-0(T) was represented by significant amounts of ai-C15:0 and moderate amounts of ai-C17:0, i-C16:0 and i-C15:0 fatty acids. Spermidine was predominant in the polyamine pattern. The G+C content of the genomic DNA was 68 mol%. Comparative 16S rDNA sequence studies revealed the highest similarity values (95.4-96.1%) between strain 4-0(T) and species of the genus Micrococcus and certain species of the genus Arthrobacter, including Arthrobacter pascens DSM 20545(T), Arthrobacter ramosus DSM 20546(T), Arthrobacterprotophormiae DSM 20168(T), Arthrobacternicotianae DSM 20123(T) and Arthrobacter globiformis DSM 20124(T). Phylogenetic analyses demonstrated that strain 4-0(T) branches deeply on the Micrococcus lineage. Because it is almost equidistant phylogenetically from the genera Micrococcus and Arthrobacter and possesses significant differences in chemotaxonomic characteristics from members of these genera, it is suggested that strain 4-0(T) be classified as a novel species in a new genus; the name Citricoccus muralis gen. nov., sp. nov. is proposed. The type strain is strain 4-0(T) (= DSM 11442(T) CCM 4981(T)).

Austria↗

Nocardiopsis metallicus sp. nov., a metal-leaching actinomycete isolated from an alkaline slag dump.

A taxonomic study was carried out on a metal-mobilizing, alkaliphilic bacterium from an alkaline slag dump, strain KBS6(T). The strain produced substrate and aerial mycelia. Growth occurred in the pH range 7.0-10.5, with an optimum at pH 8.5. A salt concentration of up to 10% was tolerated, and various organic substrates were used for growth. The results of a 16S rDNA sequence comparison revealed that strain KBS6(T) belongs to the genus Nocardiopsis. DNA-DNA hybridization with the two closest relatives, Nocardiopsis exhalans and Nocardiopsis prasina, gave similarity values of 18.2 and 44.1%, respectively, which indicated that strain KBS6(T) represents a novel species of the genus Nocardiopsis. This is consistent with the morphological, physiological and chemotaxonomic data. Because of the ability of this micro-organism to solubilize metals, the name Nocardiopsis metallicus sp. nov. is proposed for strain KBS6(T) (= DSM 44598(T) = NRRL B-24159(T)), this being the type strain.

Actinomycetales↗

Enzymes of dimethylsulfone metabolism and the phylogenetic characterization of the facultative methylotrophs Arthrobacter sulfonivorans sp. nov., Arthrobacter methylotrophus sp. nov., and Hyphomicrobium sulfonivorans sp. nov.

Novel methylotrophic Arthrobacter and Hyphomicrobium species are described. Constitutive membrane-associated dimethylsulfone- and dimethylsulfoxide-reductases were found in Arthrobacter methylotrophus strain TGA and Hyphomicrobium sulfonivorans strain S1. Enzyme activities increased during growth with dimethylsulfone or dimethylsulfoxide, respectively, and different ratios of activity with different growth substrates indicated that they are separate enzymes. SDS-PAGE showed some membrane-associated polypeptides to be enhanced during growth with dimethylsulfone (54 kDa in H. sulfonivorans, 21-24 kDa, 54 kDa and 80 kDa in A. methylotrophus). Western blotting with anti-dimethylsulfoxide-reductase antibody showed cross-reaction with 54- and 21-kDa polypeptides in A. methylotrophus. All strains contained rhodanese and sulfur oxygenase after growth with dimethylsulfone. Sulfite was oxidized in the Arthrobacter species by APS reductase and sulfite dehydrogenase. H. sulfonivorans oxidized sulfite with APS reductase, which is unusual for an alpha-proteobacterium. The Arthrobacter species were distinguished from each other and from other Arthrobacter and Micrococcus species by 16S rRNA gene sequence analysis. The menaquinone and fatty acid profiles of the Arthrobacter species were similar. Their peptidoglycan structures were L-Lys- L-Ser- L-Thr- L-Ala for A. sulfonivorans and L-Lys- L-Ala(2-4) for A. methylotrophus. H. sulfonivorans exhibited gross morphology typical for Hyphomicrobium, but possessed helically twisted prosthecae. 16S rRNA gene sequence analysis showed it to be distinct from all the other Hyphomicrobium, Filomicrobium and Pedomicrobium species sequenced to date. Formal descriptions of the new species are given.

Arthrobacter↗