Until now, no enzymes were described that hydrolyze cyanophycin granular protein (CGP) from a species of the genus Streptomyces. An isolate able to hydrolyze CGP was identified as Streptomyces pratensis strain YSM. The CGPase from S. pratensis strain YSM had an optimum activity at 42 °C and pH 8.5, and was able to degrade CGP at a rate of 12 ± 0.3 μg/mL min. Additionally, this CGPase hydrolyzes water-soluble CGP significantly faster than water-insoluble CGP. The molecular mass of CGPase subunits from S. pratensis strain YSM as determined by SDS-PAGE was about 43 kDa, and the enzyme was entirely inhibited by serine-protease inhibitors. The CGPase coding gene (cphE_Strept.) was amplified from genomic DNA using primers designed form consensus sequence of putative CGPase sequences. The cphE_Strept. was 1427 bp encoding a CGPase of 420 amino acids that showed about 44% and 22% similarities to CGPase from Pseudomonas anguilliseptica BI and Synechocystis sp. PCC 6803, respectively. The catalytic triad and serine-protease residues (GXSXG) were identified in the CphE_Strept. sequence. Dipeptides and tetrapeptides were identified as hydrolysis products. Biotechnological exploitation of S. pratensis strain YSM for CGPase production might have an advantage due to the reduction of separation costs and its ability to degrade CGP in phosphate buffer saline using actively growing or resting cells.

迄今为止，还没有描述可水解链霉菌属物种的蓝霉素颗粒蛋白（CGP）的酶。能够水解CGP的分离株被鉴定为鼠链霉菌菌株YSM。来自鼠疫沙门氏菌YSM的CGPase在42°C和pH 8.5时具有最佳活性，并且能够以12±0.3μg/ mL min的速率降解CGP。此外，这种CGPase水解水溶性CGP的速度明显快于非水溶性CGP。通过SDS-PAGE测定，来自S.pratensis菌株YSM的CGPase亚基的分子量约为43kDa，并且该酶被丝氨酸蛋白酶抑制剂完全抑制。CGPase编码基因（cphE Strept _。使用从推定的CGPase序列的共有序列设计的引物，从基因组DNA扩增）。该CPHE_链霉。该片段为1427bp，编码420个氨基酸的CGPase，与来自假单胞菌假单胞菌BI和集胞藻的CGPase显示出约44％和22％的相似性。PCC 6803分别。在CphE链中鉴定了催化三联体和丝氨酸蛋白酶残基（GXSXG）_。顺序。二肽和四肽被鉴定为水解产物。生物技术开发S.禾 用于生产CGPase的YSM菌株可能具有优势，因为分离成本降低，并且具有使用活跃生长或静止的细胞降解磷酸盐缓冲液中CGP的能力。