南海北部巴士海峡深海沉积物中几丁质酶基因多样性分析

Phylogenetic diversity analysis of chitinase gene in deep-sea sediments from the Bashi Channel in the northern South China Sea

海洋微生物是新颖几丁质酶基因的重要来源。构建南海北部巴士海峡深海表层沉积物几丁质酶基因文库,得到几丁质酶氨基酸序列共计114条。以0.3的距离划分OTU,得到54个OTU单元,丰富度指数Chao1值为159.86,多样性指数Shannon和Simpson值分别为3.39和0.06。对54条OTU单元的代表序列,利用BLAST程序与Gen Bank基因库中的序列比对,所有序列均发现具有几丁质酶基因的保守位点,相似性最高为97%,最低为41%,31个OTU单元的代表序列来自于未培养微生物。结果表明,在南海北部深海沉积环境中具有丰富的几丁质酶基因多样性,蕴藏着大量未知的几丁质酶基因资源。

Marine microbe is an important source of novel chitinase gene. The chitinase gene library of the deep-sea surface sediments of the Bashi Channel in the northern South China Sea was constructed, and 114 amino acid sequences of chitinase were obtained, which were divided into 54 operational taxonomic units （OTUs） based on 0.3 distance. The Chaol of richness index was 159.86, and the Shannon and Simpson of diversity index were 3.39 and 0.06, respectively. By BLAST analysis in GenBank, the conservative sites of chitinase gene were found in all 54 OTU representative sequences. The highest similarity was 97%, and the lowest similarity was 41%. 31 OTU representative sequences came from uncultured microbes. The results indicate that the chitinase gene diversity is quite plentiful in deep-sea sediments in the northern South China Sea, which contains a large number of unknown chitinase gene resources.