鹿角杯形珊瑚溶菌酶PdLYZ重组蛋白的表达及其体外抑菌活性特征

珊瑚疾病的大规模爆发已严重威胁到珊瑚礁生态系统的结构和功能.溶菌酶是无脊椎动物固有免疫应答中的重要效应分子之一.本研究从鹿角杯形珊瑚(Pocillopora damicornis)中克隆得到了1个溶菌酶基因(PdLYZ),随后体外诱导表达并纯化PdLYZ重组蛋白,同时测定PdLYZ重组蛋白对大肠杆菌(Escherich...

Recombinant Protein Expression and Bacteriostatic Activity of Pocillopora damicornis Lysozyme in Vitro

Large-scale outbreaks of coral diseases have been seriously threatening the health of coral reef ecosystems. Lysozyme is one of the important effectors in the innate immune response of invertebrates. A lysozyme gene, PdLYZ, was cloned from Pocillopora damicornis. The recombinant protein of PdLYZ (rPdLYZ) was expressed and purified in vitro, and its bacteriostatic activities against the Gram-positive bacteria Streptococcus mutans and Gram-negative bacteria Escherichia coli were determined. The effect of high temperature on the bacteriostatic activity of rPdLYZ against the pathogenic bacteria Vibrio coralliilyticus was further explored. The identified PdLYZ was comprised of 215 amino acid residues and predicted to contain one lysozyme-like superfamily domain (Ile31-Gly214), and its sequence was 25.54%?49.15% similar to those of lysozymes from other organisms. Results showed that rPdLYZ had lytic activities against E. coli, S. mutans and V. coralliilyticus. The rPdLYZ inhibited the growth of V. coralliilyticus at the early stage under high temperature. These results suggest that PdLYZ be involved in the immune defense of corals, and this study provides a theoretical reference for further understanding of the immune mechanism of corals.