Isolation, identification, and whole genome sequence analysis of the alginate-degrading bacterium Cobetia sp. cqz5-12
Isolation, identification, and whole genome sequence analysis of the alginate-degrading bacterium Cobetia sp. cqz5-12
复制标题
藻酸盐降解菌 Cobetia sp 的分离、鉴定和全基因组序列分析。
DOI：
10.1038/s41598-020-67921-7
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发表时间：
2020-07-02
影响因子：
4.6
通讯作者：
Chen, Qiongzhen
中科院分区：
文献类型：
--
作者：
Cheng, Wenwen;Yan, Xuanyu;Chen, Qiongzhen
可以使用藻酸盐降解菌或藻酸盐裂解酶来齐聚藻酸盐。本研究利用羊栖菜污泥，成功地筛选出一株具有较高溶藻活性的藻酸盐降解菌。在含有海藻酸钠的平板上培养时，透明环直径(D)为2.2 cm，透明环直径与菌落直径之比(D/d)为8.8。在28℃、150r/min摇床培养36h后，发酵上清酶活达到160U/m L，收获的细菌沉淀物的酶活为2645U/m L。该菌株被命名为Cobetia sp.Cqz5-12。基因组为圆形，大小为4209,007个碱基，GC含量为62.36%。它包含3498个预测编码基因、72个tRNA基因和21个rRNA基因。对编码基因的功能注释表明，基因组中与糖类运输代谢相关的编码基因有181个，未知功能的编码基因有699个。通过对碳水化合物活性酶(CAZy)数据库的分析，确定了与藻酸盐降解相关的3个可能的编码基因：alg2107、alg2108和alg2112。此外，还成功表达了海藻酸裂解酶活性的蛋白ALG2107和ALG2112。
Alginate-degrading bacteria or alginate lyases can be used to oligomerize alginate. In this study, an alginate-degrading bacterium with high alginolytic activity was successfully screened by using Sargassum fusiforme sludge. When the strain was grown on a plate containing sodium alginate, the transparent ring diameter (D) was 2.2 cm and the ratio (D/d) of transparent ring diameter to colony diameter (d) was 8.8. After 36 h in culture at a temperature of 28 degrees C shaken at 150 r/min, the enzymatic activity of the fermentation supernatant reached 160 U/mL, and the enzymatic activity of the bacterial precipitate harvested was 2,645 U/mL. The strain was named Cobetia sp. cqz5-12. Its genome is circular in shape, 4,209,007 bp in size, with a 62.36% GC content. It contains 3,498 predicted coding genes, 72 tRNA genes, and 21 rRNA genes. The functional annotations for the coding genes demonstrated that there were 181 coding genes in the genome related to carbohydrate transport and metabolism and 699 coding genes with unknown functions. Three putative coding genes, alg2107, alg2108 and alg2112, related to alginate degradation were identified by analyzing the carbohydrate active enzyme (CAZy) database. Moreover, proteins Alg2107 and Alg2112 were successfully expressed and exhibited alginate lyase activity.