Based on published results and investigations done for this study, chemotaxonomic characteristics of all validly described species of the genus Sphingomonas, as well as unnamed strains of this genus and related genera such as Rhizomonas and Blastomonas, are presented. All representatives of this group, here designated as sphingomonads, contain ubiquinone (Q-10). The two different polyamine patterns characterized either by the predominant polyamine sym-homospermidine or spermidine separate the sphingomonads into two major groups. Complex polar lipid profiles were found in sphingomonads in addition to the characteristic compound sphingoglycolipid. Identical profiles were found only in a few phylogenetically highly related species. Common to all sphingomonads is a fatty acid composition with 2-hydroxy fatty acids (14:0 2OH in all currently recognized species) and the lack of 3-hydroxy acids, which distinguishes them from taxa outside this group. Qualitative and quantitative differences in the fatty acid compositions, in several cases, were also suitable for identification at the species level. Thus, the differences in the chemotaxonomic characteristics demonstrate that the analyses of these low molecular weight cell compounds are suitable for classification of sphingomonads.

A bacterium previously isolated from a diseased colony of the scleractinian coral Dichocoenia stokesi (common name elliptical star coral) was subjected to a detailed polyphasic taxonomic characterization. The isolate, designated WP1 T , was halophilic and strictly aerobic and formed golden-orange-pigmented colonies after prolonged incubation. Cells of WP1 T were Gram-negative, rod-shaped and showed a characteristic branching rod morphology. Chemotaxonomically, WP1 T was characterized by having Q-10 as the major respiratory lipoquinone and sym-homospermidine as the main component of the cellular polyamine content. The predominant constituent in the cellular fatty acid profile was C 18 : 1 v7c, along with C 19 : 0 cyclo v8c and C 16 : 0 . Other fatty acids present in smaller amounts were C 17 : 0 , C 18 : 0 , C 16 : 1 v7c, C 20 : 1 v7c and C 18 : 1 2-OH. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Minor amounts of diphosphatidylglycerol, phosphatidylmonomethylethanolamine and phosphatidyldimethylethanolamine were present. The G+C content of the genomic DNA was 66?3 mol%. Phylogenetic analysis of the 16S rRNA gene sequence showed that WP1 T represents a separate subline of descent within the order 'Rhizobiales' of the 'Alphaproteobacteria'. The new line of descent falls within the group of families that includes the Rhizobiaceae, Bartonellaceae, Brucellaceae and 'Phyllobacteriaceae', with no particular relative within this group. The 16S rRNA gene sequence similarity to all established taxa within this group was not higher than 92?0 % (to Mesorhizobium mediterraneum). To accommodate this emerging coral pathogen, the creation of a new genus and species is proposed, Aurantimonas coralicida gen. nov., sp. nov. (type strain WP1 T =CIP 107386 T =DSM 14790 T ). INTRODUCTIONIn 1995, Richardson and co-workers documented a dramatic coral epizootic that occurred on reefs of the northern Florida Keys, which spread rapidly to infect 17 of the 43 species of scleractinian corals present. Mortality rates of up to 38 % of the most susceptible coral species, Dichocoenia stokesi (the elliptical star coral), occurred within periods as short as 10 weeks (Richardson et al., 1998a). The disease was designated white plague type II The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of Aurantimonas coralicida strain WP1 T is AJ065627.Abbreviations: DPG, diphosphatidylglycerol; PC, phosphatidylcholine; PDE, phosphatidyldimethylethanolamine; PE, phosphatidylethanolamine; PG, phosphatidylglycerol; PME, phosphatidylmonomethylethanolamine. G 2003 IUMS Printed in Great Britain1115 , 1998a). Beyond it, a replication sequence comparison between the re-determined 16S rRNA gene sequence in the study presented here and the originally deposited sequence revealed that there was no significant degree of similarity (~82 %) between the two sequences.In order to exclude any strain confusion, we have followed the history and distribution of strain WP1 T among our different laborato...

, were subjected to a polyphasic characterization to determine their taxonomic position. High 16S rDNA sequences similarities (99?3-100?0 %) demonstrated that they were closely related to each other. Phylogenetic evaluation of their 16S rDNA sequences revealed that they are members of the genus Sphingomonas sensu stricto, encompassing a separate branch within this genus. They shared 94?4-96?6 % 16S rDNA sequence similarity with species of this genus. All Sphingomonas-specific signature nucleotides were also detected. The presence of the major ubiquinone Q-10, sym-homospermidine as the predominant polyamine, Sphingomonadaceae-specific sphingoglycolipid in the polar lipid patterns and a fatty acid profile containing C 14 : 0 2-OH and lacking 3-OH fatty acids were in agreement with identification of these strains as members of the genus Sphingomonas sensu stricto.

Several strains of moderately halophilic and mesophil ic bacteria were isolated a t the head of an oil-producing well on an offshore platform in southern Vietnam. Cells were Gram-negative, non-spore-forming, rod-shaped and motile by means of a polar f lagellum. Growth occurred a t NaCl concentrations between 0 and 20%; the optimum was 5% NaCl. One strain, which was designated VT8l, could degrade n-hexadecane, pristane and some crude oil components. It grew anaerobically in the presence of nitrate on succinate, citrate or acetate, but not on glucose. Several organic acids and amino acids were utilized as sole carbon and energy sources. The major components of its cellular fatty acids were Clzr0 3-OH, c 1 6 : 1 09c, c16:o and C18:1 w9c. The DNA G+C content was 557 mol0/o. 165 rDNA sequence analysis indicated that strain VT8T was closely related to Marinobacter sp. strain CAB (99.8% similarity) and Marinobacter hydrocarbonoclasticus (99-4 YO si m i la r i t y) . Its antibiotic resistance, isoprenoid quinones and fatty acids were similar to those of Marinobacter hydrocarbonoclasticus and Pseudomonas nautica. However, the whole-cell protein pattern of VT8T differed from that of other halophilic marine isolates, including P. nautica. DNA-DNA hybridization indicated that the level of relatedness to Marinobacter hydrocarbonoclasticus was 65 O/ O and that to P. nautica was 75%. Further differences were apparent in Fouriertransformed IR spectra of cells and lipopolysaccharide composition. It is proposed that VT8T should be the type strain of a new species and should be named Marinobacter aquaeolei. P. nautica may have been misclassified, as suggested previously, and may also belong to the genus Marinobacter.

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A novel extremely halophilic archaeon (archaebacterium) was isolated from rock salt obtained from an Austrian salt mine. The deposition of the salt is thought to have occurred during the Permian period (225 X lo6 to 280 X lo6 years ago). This organism grew over a pH range of 6.8 to 9.5. Electron microscopy revealed cocci in tetrads or larger clusters. The partial 16s rRNA sequences, polar lipid composition, and menaquinone content suggested that this organism was related to members of the genus Halococcus, while the whole-cell protein patterns, the presence of several unknown lipids, and the presence of pink pigmentation indicated that it was different from previously described coccoid halophiles. We propose that this isolate should be recognized as a new species and should be named Halococcus sulifodinue. The type strain is Blp (= ATCC 51437 = DSM 8989). A chemotaxonomically similar microorganism was isolated from a British salt mine.Viable halophilic microorganisms have been isolated recently from various ancient salt deposits in England which originated in the Triassic period (195 X lo6 to 225 X lo6 years ago) or the Permian period (225 X lo6 to 280 X lo6 years ago) (18). We have also been able to cultivate halophilic bacteria from rock salt which was obtained from the Austrian salt mine near Bad Ischl; this salt is believed to have been deposited during the Permian period (30). A preliminary biochemical description of some of the isolates obtained from the British salt deposits as well as the Austrian salt mines has been published previously (24). In this paper we present a detailed characterization of one of the Austrian halophilic coccoid isolates (strain BlpT [T = type strain]) which could grow over a wide pH range, and we propose a new species, Halococcus salifodinae. MATERIALS AND METHODSCulture conditions and bacterial strains. The methods used to isolate bacteria from dry rock salt have been described previously (24). The pH of the growth medium (M2 medium [27]) was 7.4, unless indicated otherwise. When a pH of B8.5 was desired, the medium of Tindall et al. (26) was used, and the pH was adjusted accordingly. Growth in liquid cultures was monitored spectrophotometrically at 600 nm with a Novaspec I1 instrument (Pharmacia) or at 660 nm (red filter of a Klett-Summerson colorimeter). Utilization of carbohydrates was tested in minimal medium M2A, which contained 50 mM Tris-HC1, 4 M NaCl, 0.1% yeast extract, 1 mM NH,Cl, 27 mM KC1, 100 mM MgCl,, 1.4 mM CaCl,, 0.1% trace elements solution SL-6 (12), 1% carbohydrate, and 0.002% phenol red as a pH indicator. Growth on carbon sources was determine.d by monitoring turbidity and was compared with growth of a culture in minimal medium that contained no added carbohydrates. The range of salt concentrations which permitted growth was determined by spreading 10O-kl portions of a growing culture on agar plates containing M2 medium supplemented with final NaCl concentrations of 0, 0.5, 1.0, 2. 5, 5, 7.5, 10, 12.5, 15, 17.5, 20, 22.5, 25, and 30%. Cultures of strain BlpT...

A bacterial strain (Chol-1S(T)) that is able to oxidize cholesterol to CO2 and reduce nitrate to dinitrogen was enriched and isolated from an upflow sludge bed (USB) anoxic reactor that treats sanitary landfill leachate from the city of Montevideo, Uruguay. Cells of strain Chol-1S(T) were gram-negative, rod-shaped to slightly curved, measured 0.5-0.6 x 1.0-1.3 microm and were motile by a single polar flagellum. Strain Chol-1S(T) grew optimally at 30-32 degrees C and pH 7.0, with a doubling time of 44-46 h when cholesterol was used as the sole carbon and energy source. The metabolism of strain Chol-1S(T) was strictly respiratory, with oxygen or nitrate as the terminal electron acceptor. The presence of ubiquinone Q-8 as the sole respiratory lipoquinone indicated that strain Chol-1S(T) belonged to the beta-subclass of the Proteobacteria. Phosphatidylethanolamine was the predominant polar lipid and the G + C content of the DNA was 65.3 mol%. The fatty acid profile of strain Chol-1S(T), cultivated under denitrifying conditions by using a defined mineral medium supplemented with cholesterol, was characterized by the following major components: summed feature 4 (C16:1 omega7c and/or iso C15:0 2-OH), C16:0, C18:1 omega7c and hydroxy acid C10:0 3-OH. Minor components included C10:0, C11:0, C12:0, C14:0, C15:0, C19:0, C19:0 10-methyl and hydroxylated acids C8:0 3-OH and C16:0 3-OH. Analysis of the 16S rDNA sequence showed that strain Chol-1S(T) represents a separate lineage within the Thauera, Azoarcus, Zoogloea and Rhodocyclus assemblage of the beta-Proteobacteria. Strain Chol-1S(T) had highest sequence similarity (96.5%) with strain 72Chol, a denitrifying beta-Proteobacterium. On the basis of polyphasic evidence, strain Chol-1S(T) (=DSM 13999T=ATCC BAA-354T) is proposed as the type strain of Sterolibacterium denitrificans gen. nov., sp. nov.

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.