In the course of isolating bacteria from infective juveniles of the entomopathogenic nematode Steinernema thermophilum Ganguly & Singh, 2000, three isolates were obtained (OP1 T , OP29 and VS3). On the basis of 16S rRNA gene sequence analysis and riboprint patterns, these three strains were identical to each other but distinct from the type strains of the five recognized species of the genus Providencia. Based on biochemical and genomic analysis and supported by the low (<35 %) DNA-DNA relatedness between strain OP1 T and the type strain of its phylogenetically closest relative, Providencia rettgeri (99?5 % 16S rRNA gene sequence similarity), strain OP1 T was considered to be sufficiently distinct from recognized Providencia species to warrant the description of a novel species. The name Providencia vermicola sp. nov. is proposed, with OP1 T (=DSM 17385 T =CIP 108829 T ) as the type strain.The enterobacterial genus Providencia comprises five species that have been isolated from the colon and faeces of humans (Providencia alcalifaciens, Providencia rustigianii), wounds, urinary tract and respiratory tract of humans (Providencia stuartii), urinary tract of humans, poultry, faeces from reptiles and other environments (Providencia rettgeri) and from faeces of penguins (Providencia heimbachae) [summarized by Penner (1991)]. P. alcalifaciens and P. stuartii are known for their pathogenic potential, causing diarrhoea and bacteraemia, respectively. The description of several of these species was initially based upon DNA-DNA reassociation experiments, which indicated their previous misclassification in other genera or affiliation to other species (Brenner et al., 1978; Hickman-Brenner et al., 1983; Müller et al., 1986). The five species can be separated based on metabolic characteristics, such as acid production from some carbohydrates and several other standard tests (Müller et al., 1986).The type strains of Providencia species (Table 1) were obtained from the DSMZ. Isolation was performed as described by Akhurst (1980): a mixture of infective juveniles (IJs) of nematodes of Steinernema thermophilum belonging to different age groups, isolated from different larvae of the greater wax moth (Galleria mellonella), were surface sterilized in 0?1 % Hyamine 106 (methylbenzethonium chloride; Spectrum Chemicals & Laboratory Products) for 15-30 min. Nematodes were then washed three times in sterilized water in order to remove traces of Hyamine. The surface-sterilized IJs were suspended in Luria-Bertani (LB) broth or nutrient broth in a 1?5 ml microcentrifuge tube. Subsequently, the IJs were crushed manually by using a sterile tissue grinder. One loopful of the crushed suspension was then used to streak the indicator NBTA (5?0 g peptone, 3?0 g beef extract, 15 g agar, 0?025 g bromothymol blue, 0?04 g 2,3,5-triphenyl tetrazolium chloride; per litre of water) media plates. The plates were incubated for 24 h at 28 u C; individual colonies were purified by restreaking them onto fresh solid media. Isolates OP1 T , OP29 and VS3 were i...

This is the first study to demonstrate that diverse methylotrophic bacteria occur in the human foot microflora. Polymerase chain reaction (PCR) amplification of DNA from the soles and toe clefts of feet of five subjects indicated Methylobacterium strains to be present in all cases. Polymerase chain reaction amplification also showed the gene for the alpha-subunit of methanol dehydrogenase (mxaF) to be present in all samples. Two types of mxaF were recovered, one closest to that of Methylobacterium extorquens and the other most similar to that of Hyphomicrobium methylovorum. Numerous methylotrophic strains able to grow on methylamine were isolated with ease from the feet of nine volunteers. These were found by 16S rRNA analysis to be most closely related to Methylobacterium species, Brevibacterium casei, Pseudomonas strain NZ099 and P. migulae. Three strains from two subjects were of a novel species, Methylobacterium podarium sp. nov. This facultatively methylotrophic, obligately aerobic, pink-pigmented, non-motile rod grew with a wide range of multicarbon and one-carbon compounds including citrate, xylose, mono-, di-, and trimethylamine, dimethylsulphide, methanethiol, dimethylsulphoxide, dimethylsulphone and methanol.

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.

No abstract

Strain DSM 44594T , which produces the glycopeptide antibiotic decaplanin, is a member of the genus Amycolatopsis based on 16S rRNA gene sequence analysis and chemotaxonomic properties. It is the first member of this genus that is reported to form pseudosporangia, which resemble those of members of the genus Kibdelosporangium. Phylogenetically, the novel taxon is related to Amycolatopsis orientalis, Amycolatopsis lurida, Amycolatopsis azurea, Amycolatopsis japonica and Amycolatopsis keratiniphila. Morphological, cultural and physiological properties, the production of a unique glycolipid and DNA-DNA similarity of <55 % with phylogenetically related strains reveal that strain DSM 44594 T represents a novel species of the genus, for In the course of a screening programme in Hoechst, Frankfurt, for new antibiotics that are active against methicillin-resistant strains of Staphylococcus aureus, the strain that produces the new antibiotic decaplanin (Eur. Pat., 1990, EP 356894) was isolated from a soil sample from India. Strain FH 1845 T (=DSM 44594 T =NRRL B-24209 T ) displays activity against a wide range of Grampositive bacteria, including enterococci and clinical isolates, that are resistant to commonly applied antibiotics (Sanchez et al., 1992). Micrographs of the strain described in this study are shown in Fig. 1. Morphological and physiological characteristics of DSM 44594 T were observed on various agar cultures as described by Shirling & Gottlieb (1966): yeast extract/malt extract agar (ISP 2), oatmeal agar (ISP 3), inorganic salt/starch agar (ISP 4), glycerol/asparagine agar (ISP 5), peptone/yeast extract/iron agar (ISP 6) and tyrosine agar (ISP 7), incubated for 10 days at 28 u C. For scanning electron microscopy (Grabley et al., 1992), the strain was grown on ISP 3 agar. A honey-yellow vegetative mycelium developed on all ISP media tested (RAL colour code 1005; Deutsches Institut für Gütesicherung und Kennzeichnung e.V. -Reichsausschuß für Lieferbedingungen). Aerial mycelium was only formed on ISP 3 medium and a soluble red pigment was produced on ISP 7 medium. After 7-10 days on ISP 3 medium, sporangium-like elements were formed. These elements showed a smooth surface and a regular shape under the scanning electron microscope. Spores were not detected either inside or outside the pseudosporangia.Utilization of carbohydrates was investigated on ISP 9 medium (Shirling & Gottlieb, 1966) by using a 12-well microtitre plate technique. Sodium chloride tolerance was also tested on 6-well microtitre plates by using a technique based on the method of Kutzner et al. (1986). A fingerprint of enzymic activities was obtained by using API 20E and API ZYM test strips (Smith et al., 1972;Humble et al., 1977;Kilian, 1978). Reactions are indicated in the species description.To determine the antimicrobial spectrum (Williams et al., 1989), bacteria were grown on Mueller-Hinton agar and fungi on Czapek Dox agar. Antibacterial activity was seen after cultivation on ISP 2, ISP 3 and starch media, especially against Staphylococc...