School of Biotechnology, University of Jammu, Jammu 180 006, India.
N Biotechnol. 2011 Oct;28(6):725-32. doi: 10.1016/j.nbt.2011.01.001. Epub 2011 Jan 11.
Of six alkalitolerant, extracellular protease producing bacterial strains isolated, DP2 displayed maximum activity. This organism was designated as Streptomyces sp. DP2 and identified as Streptomyces ambofaciens. Maximum protease yield was observed after 48hours of submerged fermentation using various carbon and nitrogen sources. Fructose was found to be the best substrate for protease production, followed by maltose, lactose and wheat bran. Mustard cake is reported for the first time as the most ideal nitrogen source although soybean meal also gave comparable yield. The protease produced by Streptomyces sp. DP2 exhibited extensive activity over a broad pH range (4-12) with maximum activity at pH 8, and was active over a broad range of elevated temperatures (50-100°C), and possessed thermostability at 60-90°C for up to 1 hour. Enzyme activity was reduced by EDTA (25%), SDS (16%), and PMSF (6%). This novel alkaline protease has both alkali- and thermostability that may have industrial significance.
从六种耐碱、能分泌胞外蛋白酶的细菌菌株中分离到 DP2 号菌株，其蛋白酶活性最高。该菌被命名为 DP2 号链霉菌，并鉴定为 ambofaciens 链霉菌。在不同的碳源和氮源进行深层发酵 48 小时后，观察到最大蛋白酶产量。发现果糖是产生蛋白酶的最佳底物，其次是麦芽糖、乳糖和麦麸。尽管豆粕也能产生相当的产量，但据报道，芥末饼是最理想的氮源。DP2 号链霉菌产生的蛋白酶在较宽的 pH 范围（4-12）内具有广泛的活性，在 pH8 时活性最高，在较宽的高温范围（50-100°C）内具有活性，在 60-90°C 下具有热稳定性，可达 1 小时。酶活性被 EDTA（25%）、SDS（16%）和 PMSF（6%）降低。这种新型碱性蛋白酶具有耐碱和耐热性，可能具有工业意义。
