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Multiple proteases were produced and partially purified from an alkali-thermotolerant novel species of Streptomyces (i.e., Streptomyces gulbargensis DAS 131) after 48 h of growth at 45 degrees C. The enzyme preparation exhibited activity over a broad range of pH (4-12) and temperature (27-55 degrees C). Optimum activity was observed at a pH of 9.0 and a temperature of 45 degrees C. Starch and protease peptone was found to be a good source of carbon and nitrogen to enhance the enzyme activity. Two active zones in the range of 19 to 35 kDa were detected on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).

A short coccoid-rod-shaped, nonmotile actinobacteria strain MSL-11T was isolated from soil in Bigeum Island, Korea. A polyphasic study was undertaken to establish the taxonomic position of this strain. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain MSL-11T forms an evolutionary lineage within the radiation of the genus Nocardioides. The cell wall peptidoglycan of strain MSL-11T contained LL-diaminopimelic acid, indicating wall chemotype I. The predominant menaquinone was MK-8(H4). Strain MSL-11T had a cellular fatty acid profile containing straight-chain, branched, unsaturated, and 10-methyl fatty acids, with iso-C16:0 as a major fatty acid component detected. The DNA G + C content of the strain was 71.8 mol%. Comparative 16S rRNA gene sequencing revealed that the strains constituted a distinct subclade within the genus Nocardioides, displaying a 16S rRNA gene sequence similarity of about 95.68% with Nocardioides jensenii DSM 20641T. On the basis of both phenotypic and phylogenetic evidence, the strain is separated from previously described Nocardioides species and should be assigned to represent a novel species of the genus Nocardioides, for which the name Nocardioides dilutes sp. nov. is proposed. The type strain is strain MSL-11T (= KCTC 19288T = DSM 19318T).

A novel Gram-negative, motile, rod-shaped, facultative anaerobic bacterial strain, KMK6(T), was isolated from soil contaminated with textile dyes from an industrial estate located at Ichalkaranji, Maharashtra, India, and its taxonomical position was established by using a polyphasic approach. The major cellular fatty acids included C17:1ω8c, summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH), C17:0, C16:0, and C18:1ω7c. The DNA G+C content of strain KMK6(T) was 48.8 mol %. 16S rRNA gene sequence analysis confirmed its placement in the genus Alishewanella, and exhibited sequence similarity levels of below 97 % to the type strains of validly published Alishewanella species. On the basis of genotypic and phenotypic evidence, strains KMK6(T) is considered to be a novel species of the genus Alishewanella, for which we propose that strain KMK6(T) (=NCIM 5295(T) =BCRC 17848(T)) is assigned to a novel species, Alishewanella solinquinati sp. nov.

The occurrence and distribution of an actinobacteria group of bacteria capable of dissolving insoluble phosphates were investigated in this study in marine environments, especially in sediments of Chorao Island, Goa Province, India. A total of 200 bacterial isolates of actinobacteria was isolated. All isolates were screened for phosphate-solubilizing activity on Pikovskaya's agar. Thirteen different isolates exhibiting maximum formation of halos (zone of solubilization) around the bacterial colonies were selected for quantitative estimations of P-solubilization. Quantitative estimations for P-solubilization were analyzed for up to 10 days at intervals of 24 h. Maximum solubilization from 89.3 ± 3.1 to 164.1 ± 4.1 μg ml(-1) was observed after 6 days of incubation in six of all isolates, while the isolate NII-1020 showed maximum P-solubilization. The increase in solubilization coincided with the drop in pH. Many of these species showed wide range of tolerance to temperature, pH, and salt concentrations. Further, 16S rRNA gene sequence analyses were carried to identify the bacterial groups which are actively solubilized phosphate in vitro. Gene sequencing results reveal that all isolates were clustered into six different actinobacterial genera: Streptomyces, Microbacterium, Angustibacter, Kocuria, Isoptericola, and Agromyces. The presence of phosphate-solubilizing microorganisms and their ability to solubilize phosphate were indicative of the important role played by bacteria in the biogeochemical cycle of phosphorus and the plant growth in coastal ecosystems.