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A polyphasic taxonomic study of a halotolerant micro-organism, isolated from Kuwait salt marsh soil, revealed that this strain represents a novel Nocardiopsis species. The strain produced substrate and aerial mycelium, grew at 28-35 degrees C in salt concentrations of 0-15% and was slightly keratinolytic. Results of the 165 rDNA sequence comparison revealed that strain F100T clustered with strains of the genus Nocardiopsis. This is consistent with other data such as: (i) growth characteristics, i.e. the formation of a white to yellow aerial mycelium and the typical zig-zag form of hyphae, which fragment when ageing; (ii) the presence of DL-diaminopimelic acid and glucose plus ribose in whole-cell hydrolysates; (iii) the presence of phosphatidyl choline, phosphatidyl inositol, phosphatidyl glycerol, phosphatidyl methylethanolamine and diphosphatidyl glycerol in polar lipid extracts; (iv) the presence of menaquinones MK-10(H(0-6)) and MK-11(H(0-6)) in the non-polar fraction; (v) the presence of iso/anteiso-branched plus 10-methyl-branched fatty acids, showing the diagnostic combination for Nocardiopsis spp. of 14-methyl-hexadecanoic acid (18%), oleic acid (9%) and tuberculostearic acid (2%); and (v) the absence of mycolic acids. Analysis of 16S rDNA revealed that strain F100T represents a distinct taxon within Nocardiopsis. Based upon phenotypic differences to other members of the genus, a novel species, Nocardiopsis halotolerans sp. nov., is proposed. The type strain of the species is F100T (= DSM 44410T = NRRL B-24124T).

An actinomycete, strain 8T, was isolated from marsh soil in Kuwait. The strain was aerobic, gram-positive, halophilic and produced light blue to greyish aerial mycelium. The warty spores were sessile, occurring singly or in pairs on aerial mycelium. The mycelium was stable and did not fragment during ageing. Chemotaxonomic markers of the isolate were consistent with its classification as Saccharomonospora. The strain possessed meso-diaminopimelic acid as the diagnostic amino acid in the peptidoglycan. The diagnostic sugars were arabinose and galactose; polar lipids were phosphatidyl inositol, phosphatidyl ethanolamine, hydroxy-phosphatidyl ethanolamine, lyso-phosphatidyl ethanolamine and diphosphatidyl glycerol; the principal menaquinone was MK-9(H4); and the iso/anteiso-branched fatty acid pattern was combined with 10-methyl-branched and 2-hydroxy-branched fatty acids. Saccharomonospora cyanea DSM 44106T was the closest phylogenetic neighbour of strain 8T, showing 96.8% 16S rDNA sequence similarity. These data, together with distinct physiological traits, led to the conclusion that the novel isolate represents a new species within the genus Saccharomonospora for which the name Saccharomonospora halophila sp. nov. is proposed. The type strain is strain 8T (= DSM 44411T =NRRL B-24125T).

A keratinolytic, nocardioform actinomycete, strain D2(T), was isolated from Kuwait marsh soil by the bait technique using animal wool. Strain D2(T) was an aerobic, Gram-positive organism that produced light-grey aerial mycelium but no specific spore chains. 16S rDNA sequence analyses and chemotaxonomic markers were consistent with the classification of strain D2(T) in the genus Amycolatopsis, i.e. it had meso-diaminopimelic acid in its peptidoglycan, arabinose and galactose as its diagnostic sugars, the polar lipids phosphatidylinositol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine and diphosphatidylglycerol, menaquinone MK-9(H4) and an iso-/anteiso-branched fatty acid pattern combined with 10-methyl-branched and 2-hydroxy-branched fatty acids. Amycolatopsis japonica was the closest phylogenetic neighbour of strain D2(T), showing 99.4% 16S rDNA sequence similarity with the novel strain. A. japonica and strain D2(T) could be clearly separated from each other on the basis of their low DNA-DNA reassociation value (55.9%). These data, together with its distinct physiological traits, led to the conclusion that strain D2(T) represented a novel species within the genus Amycolatopsis, for which the name Amycolatopsis keratiniphila (type strain D2(T) = DSM 44409(T) = NRRL B24117(T)) is proposed.