ABSTRACT
Novel orange-pigmented, Gram-negative, rod-shaped, non-motile bacteria, designated strains NIO-S3(T) and NIO-S4, were isolated from a water sample collected from Cochin back waters, Thanneermukkom and Arookutty, Kerala, India. Both strains were positive for oxidase and catalase activities, and hydrolyzed gelatin and Tween 40. The predominant fatty acids were iso-C15:0, anteiso-C15:0, iso-C17:0 3OH, C16:1ω7c/C16:1ω6c (summed feature 3) and iso-C17:1ω9c/C16:0 10-methyl (summed feature 9), whereas MK-7 was the major respiratory quinone, and phosphatidylethanolamine, two unidentified phospholipids and one unidentified lipid were the only polar lipids. The DNA G+C content of the two strains was 43.7 and 43.6mol%, respectively. The 16S rRNA gene sequence analysis indicated that they were members of the genus Algoriphagus and closely related to Algoriphagus olei CC-Hsuan-617(T), Algoriphagus aquatilis A8-7(T), Algoriphagus aquaeductus LMG 24398(T) and Algoriphagus mannitolivorans DSM 15301(T), with pairwise sequence similarities of 96.8, 96.6, 96.2 and 96.2%, respectively. DNA-DNA hybridization between strains NIO-S3(T) and NIO-S4 showed a relatedness of 89%. Based on data from the current polyphasic study, the strains are proposed as a novel species of the genus Algoriphagus, for which the name Algoriphagus shivajiensis sp. nov. is proposed. The type strain of A. shivajiensis is NIO-S3(T) (=JCM 17885(T)=MTCC 11066(T)).
Subject(s)
Bacteroidetes/classification , Bacteroidetes/isolation & purification , Water Microbiology , Bacterial Typing Techniques , Bacteroidetes/genetics , Bacteroidetes/physiology , Base Composition , Catalase/metabolism , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fatty Acids/analysis , Gelatin/metabolism , Hydrolysis , India , Molecular Sequence Data , Oxidoreductases/metabolism , Phospholipids/metabolism , Phylogeny , Pigments, Biological/metabolism , Polysorbates/metabolism , Quinones/analysis , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNAABSTRACT
The feasibility of laccase production by immobilization of Pleurotus ostreatus 1804 on polyurethane foam (PUF) cubes with respect to media composition was studied in both batch and reactor systems. Enhanced laccase yield was evidenced due to immobilization. A relatively high maximum laccase activity of 312.6 U was observed with immobilized mycelia in shake flasks compared to the maximum laccase activity of free mycelia (272.2 U). It is evident from this study that the culture conditions studied, i.e. biomass level, pH, substrate concentration, yeast extract concentration, Cu2+ concentration, and alcohol nature, showed significant influence on the laccase yield. Gel electrophoretic analysis showed the molecular weight of the laccase produced by immobilized P. ostreatus to be 66 kDa. The laccase yield was significantly higher and more rapid in the packed bed reactor than in the shake flask experiments. A maximum laccase yield of 392.9 U was observed within 144 h of the fermentation period with complete glucose depletion.
