Biodiversity analysis of cultivable bacteria isolated from marine sediments collected during 6th Arctic Expedition

Abstract:

[Objective] Investigating the diversity of the cultivable bacteria in Arctic Ocean sediments. [Methods] Culturable bacteria were isolated from marine sediments collected during the 6^th Chinese National Arctic Expedition (Arc6) by marine Zobell 2216E medium and spread plate method. Subsequently, 16S rRNA gene sequence similarity analysis and phylogenetic analysis were performed. [Results] A total of 445 strains were isolated from 40 sediments samples. According to the results of 16S rRNA gene sequence similarity as well as phylogenetic analysis, the isolates belong to 4 phyla, 6 classes, 13 orders, 28 families, 49 genera and 91 species. Twelve isolates having 16S rRNA gene similarity less than 97% with the closest type strain were grouped into 6 independent clusters, implying that these isolates might be six novel species. Our study also indicated that the genus composition of the strains from 6^th Arctic Expedition were strikingly different with that from 5^th Arctic Expedition (Arc5). [Conclusion] There are abundant microbial resources and many novel microbes in Arctic Ocean sediments, and it is to be developed in the treasure house of microorganisms.