Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad-500 046, India.
Bioresour Technol. 2012 May;112:261-9. doi: 10.1016/j.biortech.2012.02.062. Epub 2012 Feb 21.
Serratia proteamaculans 568 genome revealed the presence of four family 18 chitinases (Sp ChiA, Sp ChiB, Sp ChiC, and Sp ChiD). Heterologous expression and characterization of Sp ChiA, Sp ChiB, and Sp ChiC showed that these enzymes were optimally active at pH 6.0-7.0, and 40°C. The three Sp chitinases displayed highest activity/binding to β-chitin and showed broad range of substrate specificities, and released dimer as major end product from oligomeric and polymeric substrates. Longer incubation was required for hydrolysis of trimer for the three Sp chitinases. The three Sp chitinases released up to tetramers from colloidal chitin substrate. Sp ChiA and Sp ChiB were processive chitinases, while Sp ChiC was a non-processive chitinase. Based on the known structures of ChiA and ChiB from S. marcescens, 3D models of Sp ChiA and Sp ChiB were generated.
变形气单胞菌 568 基因组揭示了存在四种家族 18 几丁质酶（Sp ChiA、Sp ChiB、Sp ChiC 和 Sp ChiD）。Sp ChiA、Sp ChiB 和 Sp ChiC 的异源表达和特性表明，这些酶在 pH6.0-7.0 和 40°C 下具有最佳活性。这三种 Sp 几丁质酶对β-几丁质表现出最高的活性/结合，具有广泛的底物特异性，并从低聚物和聚合物底物中释放二聚体作为主要终产物。三种 Sp 几丁质酶水解三聚体需要更长的孵育时间。这三种 Sp 几丁质酶从胶体几丁质底物中释放出多达四聚体。Sp ChiA 和 Sp ChiB 是具有连续性的几丁质酶，而 Sp ChiC 是非连续性的几丁质酶。根据来自粘质沙雷氏菌的 ChiA 和 ChiB 的已知结构，生成了 Sp ChiA 和 Sp ChiB 的 3D 模型。
