Diversity of cultivable protease-producing bacteria and their extracellular proteases associated to scleractinian corals

PeerJ

article

Hongfei Su¹  Zhenlun Xiao¹  Kefu Yu¹  Qinyu Huang³  Guanghua Wang¹  Yinghui Wang¹  Jiayuan Liang¹  Wen Huang¹  Xueyong Huang¹  Fen Wei¹  Biao Chen¹ 

[1] Coral Reef Research Center of China, Guangxi University;Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University;School of Marine Sciences, Guangxi University

关键词: Diversity;    Cultivable;    Protease-producing bacteria;    Scleractinian corals;    Extracellular protease diversity;    Hydrolytic ability;    Serine proteases;    Metalloprotease;    Firmicutes;    Proteobacteria;   

DOI  :  10.7717/peerj.9055

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Protease-producing bacteria play a vital role in degrading organic nitrogen in marine environments. However, the diversity of the bacteria and extracellular proteases has seldom been addressed, especially in communities of coral reefs. In this study, 136 extracellular protease-producing bacterial strains were isolated from seven genera of scleractinian corals from Luhuitou fringing reef, and their protease types were characterized. The massive coral had more cultivable protease-producing bacteria than branching or foliose corals. The abundance of cultivable protease-producing bacteria reached 106 CFU g−1 of coral. Phylogenetic analysis of 16S rRNA gene sequences revealed that the isolates were assigned to 24 genera, from which 20 corresponded to the phyla Firmicutes and Proteobacteria. Bacillus and Fictibacillus were retrieved from all coral samples. Moreover, Vibrio and Pseudovibrio were most prevalent in massive or foliose coral Platygyra and Montipora. In contrast, 11 genera were each identified in only one isolate. Nearly all the extracellular proteases from the bacteria were serine proteases or metalloproteases; 45.83% of isolates also released cysteine or aspartic proteases. These proteases had different hydrolytic ability against different substrates. This study represents a novel insight on the diversity of cultivable protease-producing bacteria and their extracellular proteases in scleractinian corals.

【 授权许可】

CC BY