marine sediment sample Raw sequence reads

The marine environment is an important source of microorganisms, and sample pre-treatment affacts the isolation of culturable microorganisms. However, the drying treatment of samples, one of the pre-treatment methods for isolation, has not yet adequately been evaluated. In order to explore the diversity of isolated cultivable microorganisms under different drying conditions, three marine samples were dried and incubated in 3 different temperatures for 14 days. The cultivable colonies were eluted and the DNA of the colony was extracted. The V4 region of 16S rRNA gene was sequenced using Illumina MiSeq platform. The 16S rRNA gene sequence data was analyzed using QIIME2. Alpha diversity indices of the cultivable microbial communities under different treatments were calculated and compared. We also performed non-metric multidimensional scaling and principal co-ordinates analysis based on Jaccard distance matrix. The dominant phyla in the original samples were Proteobacteria, Actinobacteria, Firmicutes, and Epsilonbacteraeota. In contrast, Firmicutes was most abundant in the samples with different drying treatments. In conclusion, in the process of isolation and cultivation of marine sediment samples, the cultivation temperature rather than drying conditions was the largest separation between cultivable microbial communities. It is possible that drying treatments did not result in the isolation of members of rarely isolated groups and the differences among microbial communities, but increased the counts and size of colonies of commonly cultivable species.