Mutation induced enhanced biosynthesis of lipase

The purpose of the present investigation is to enhance production of biomedically important enzyme lipase by subjecting the indigenous lipase producing strain Rhizopus sp. BTS-24 to improvement by natural selection and random mutagenesis (UV and N-methyl-N'-nitro-N-nitroso guanidine, NTG). The isolation of mutants and the lipolytic activity of selected mutants were described. The best natural selectant BTNS12 showed 110% higher lipase activity than the wild strain (BTS-24). The lipase yield of the best UV mutant BTUV3 was 164% higher than the parent strain (BTNS12) and 180% times higher than the wild strain (BTS-24). Also, the lipase yield of the best NTG mutant BTNT2 was 133 % higher than the parent strain (BTUV3) and 232% higher than the wild strain (BTS-24). The results indicated that UV and NTG were effective mutagenic agents for strain improvement of Rhizopus sp. BTS-24 for enhanced lipase productivity. Key Words: Lipase, Rhizopus, UV, NTG. African Journal of Biotechnology Vol.3(11) 2004: 618-62

Screening, production and biochemical characterization of a new fibrinolytic enzyme produced by Streptomyces sp. (Streptomycetaceae) isolated from Amazonian lichens

Thrombosis is a pathophysiological disorder caused by accumulation of fibrin in the blood. Fibrinolytic proteases with potent thrombolytic activity have been produced by diverse microbial sources. Considering the microbial biodiversity of the Amazon region, this study aimed at the screening, production and biochemical characterization of a fibrinolytic enzyme produced by Streptomyces sp. isolated from Amazonian lichens. The strain Streptomyces DPUA1576 showed the highest fibrinolytic activity, which was 283 mm2. Three variables at two levels were used to assess their effects on the fibrinolytic production. The parameters studied were agitation (0.28 - 1.12 g), temperature (28 - 36 ºC) and pH (6.0 - 8.0); all of them had significant effects on the fibrinolytic production. The maximum fibrinolytic activity (304 mm2) was observed at 1.12 g, 28 ºC, and pH of 8.0. The crude extract of the fermentation broth was used to assess the biochemical properties of the enzyme. Protease and fibrinolytic activities were stable during 6 h, at a pH ranging from 6.8 to 8.4 and 5.8 to 9.2, respectively. Optimum temperature for protease activity ranged between 35 and 55 °C, while the highest fibrinolytic activity was observed at 45 ºC. Proteolytic activity was inhibited by Cu2+ and Co2+ ions, phenylmethylsulfonyl fluoride (PMSF) and pepstatin A, which suggests that the enzyme is a serine protease. Enzymatic extract cleaved fibrinogen at the subunits A-chain, A-chain, and -chain. The results indicated that Streptomyces sp. DPUA 1576 produces enzymes with fibrinolytic and fibrinogenolytic activity, enzymes with an important application in the pharmaceutical industry.The authors grateful acknowledge the financial support of Fundação de Amparo a Pesquisa do Estado de Pernambuco (FACEPE, Pernambuco, Brazil, N. 0158-2.12/11), CNPq/ RENORBIO (National Counsel of Technological and Scientific Development, N.55146/2010-3) and National Council for the Improvement of Higher Education (CAPES, Brazil) for the scholarship. The author thanks editor and reviewers for their review and comments.info:eu-repo/semantics/publishedVersio

Production of Alkaline Protease by Immobilized Cells of Alkalophilic <i>Bacillus</i> sp.

589-592Different materials viz. alginate, -carrageenan and polyacrylamide gels were examined for immobilization of whole cells of Bacillus sp. PE-11 and used for the production of alkaline protease. The effect of alginate concentration, incubation time and curing time on alkaline protease production and stability of biocatalyst were investigated. The immobilized cells of Bacillus sp. PE-11 in calcium alginate are more efficient for the production of alkaline protease with repeat batch fermentation for 9 days. </span

Response Surface Optimization of the Cultural Conditions for the Production of Alkaline Protease

868-875Bacillus sp (PE-11), the most potent producer of alkaline protease was used for the production of alkaline protease. Response surface methodology was used to achieve the optimization of the experimental conditions for the optimal production of alkaline protease. To study the proposed second-order polynomial model, the central composite experimental design with multiple linear regression was used to estimate the model coefficients of the five selected factors. These factors were considered to influence the optimization process. The best yields were obtained at pH of 8.0, 35oC, rpm 280, incubation time 72 h, and 7.5 per cent level of salt solution. This methodology was found to be very efficient and only 36 experiments were needed to assess these conditions. The model adequacy was very satisfactory, as the coefficient of determination was 0.93057

Isolation of actinomycetes from marine sediments off Visakhapatnam, east coast of India

134-135Actinomycetes (140) were isolated from sediment samples and identified to generic level. The genera encountered were Streptomyces, Micromonospora, Nocardia, Streptosporangium, Micropolyspora and Streptoverticillium. Of the total isolates 18% exhibited antimicrobial activity. The salt tolerance of the isolates was also tested

Studies on the Bio-Active Alkalophilic Actinomycetes From Terrestrial Substrates

ABSTRACT Twenty four actinomycetes were isolated and tested against antimicrobial, amylolytic and proteolytic activities. The extracellular protease production potential was studied for one of the best isolate which resulted in highest yield (235µg/ml) of protease

Short Communication- Mutation induced enhanced biosynthesis of lipase

The purpose of the present investigation is to enhance production of biomedically important enzyme lipase by subjecting the indigenous lipase producing strain Rhizopus sp. BTS-24 to improvement by natural selection and random mutagenesis (UV and N-methyl-N'-nitro-N-nitroso guanidine, NTG). The isolation of mutants and the lipolytic activity of selected mutants were described. The best natural selectant BTNS12 showed 110% higher lipase activity than the wild strain (BTS-24). The lipase yield of the best UV mutant BTUV3 was 164% higher than the parent strain (BTNS12) and 180% times higher than the wild strain (BTS-24). Also, the lipase yield of the best NTG mutant BTNT2 was 133 % higher than the parent strain (BTUV3) and 232% higher than the wild strain (BTS-24). The results indicated that UV and NTG were effective mutagenic agents for strain improvement of Rhizopus sp. BTS-24 for enhanced lipase productivity

A Review on Microbial Alkaline Proteases

690-704Alkaline proteases are of considerable interest in view of their activity and stability at alkaline pH. This review, describes the proteases that can resist extreme alkaline environments produced by a wide range of alkalophilic microorganisms. Different isolation methods which enable the screening and selection of promising organisms for industrial production are discussed. The various nutritional and environmental parameters affecting the production of alkaline proteases are delineated. The production of proteases by free and immobilized whole cells is discussed. The purification, properties, and applications of these proteases are also discussed