Bacterial Diversity And Mining Of Bacillus-like Resources In Offshore Marine Sediments Of Fujian Province

In this study,the 51 soil samples were taken along the regions following the line of the sea such as Lianjiang,Zhangzhou and Xiapu city in Fujian Province for analysis of microbial community and diversity by the 16S rRNA V3-V5 region gene based on an Illumina MiSeq high-throughput sequencing platform.Among which it was tested to obtaine 428,3227 sequences and the bacterial OTU(Operational taxonomic unit)were 16686,respectively,belonging to the definite taxonomic bacteria of 61 phylum 173 classes 1446 genera and 3074 species.The diversity index analysis showed that in three areas,the lowest microbial diversity was soil samples of Xiapu and the highest microbial diversity was soil samples from Zhangzhou.The main phyla were Bacteroidetes,Firmicutes,Proteobacteria and Chloroflexi.In summer and spring two seasons of Zhangzhou Yunxiao mangrove rhizosphere 16 soil samples,1636973 sequences were obtained from soil samples and the species annotation OTU(Operational taxonomic unit)numbers of bacteria were 8743,respectively,belonging to definite taxonomic bacteria of 53 phylum 153 classes 1019 genera and 2168 species.The diversity index analysis showed that the higher microbial diversitythe was the summer than spring soil samples.Bacterial dominant groups were Proteobacteria(56.66%),followed by Chloroflexi(11.08%).51 soil samples were collected from Lianjiang,Zhangzhou and Xiapu city,Fujian Province of China,aiming to isolate Bacillus-like resources,identified by polyphasic method.Using the cultural method,993 strains of Bacillus-like,and 111 species were isolated from soil samples.There were 58 species of Chinese distribution,53 species of newly recorded Bacillus in China and 9 new species.1)under routine conditions,621 strains of Bacillus-like species were isolated from soil samples.Based on the result of 16S rRNA gene similarities and phylogeny analysis,it was indicated that 621 strains belonged to 11 genera including 69 species.6 strains were considered as new potential species of Bacillus-like species,which 16S rRNA similarities were less than 98%.2)At 55-60? temperature,84 strains of Bacillus-like species were isolated from soil samples.Based on the result of 16S rRNA gene similarities and phylogeny analysis,it was indicated that 84 strains belonged to 8 genera including 26 species.2 strains were considered as new potential species of Bacillus-like species,which 16S rRNA similarities were less than 98%.3)On LB plate with 20%NaCl,67 strains of Bacillus-like species were obtained.Based on the result of 16S rRNA gene similarities and phylogeny analysis,it was indicated that 67 strains belonged to 3 genera including 9 species.4)253 strains of Bacillus-like species were isolated from in summer and spring two seasons of Zhangzhou Yunxiao mangrove rhizosphere soil samples.Based on the result of 16S rRNA gene similarities and phylogeny analysis,it was indicated that 253 strains belonged to 7 genera including 55 species.Soil samples in three regions,the distribution characteristics of Bacillus-like species among regions were quite different,but the dominant genus was Bacillus.Based on analysis of geographical distribution diversity index,it was found that the Shannon(H')index order was Lianjiang>Xiapu>Zhangzhou respectively.A new potential species of Bacillus were identified by polyphasic method.The results were as followed.Cells of strain FJAT-46582T were aerobic,endospore-forming and motile.Temperature range for growth was 10 to 30?(optimum at 25 ?).pH range for growth was 6.0?11.0(optimum at 8.0).NaCl concentration range for growth was 0?7%(w/v)(optimum at 0%).16S rRNA gene sequence-based phylogenetic analysis revealed strain FJAT-46582T most closely related to Bacillus thermotolerans SGZ-8T(97.55%)and their DNA-DNA hybridization(isDDH)value was22.9%and their average nucleotide identity(ANI)value was72.3%.The DNA G+C content was 44.2 mol%.The major cellular fatty acids of strain FJAT-46582T were anteiso-C15:0?iso-C15:0?anteiso-C17:0 and C16:0.The diagnostic diamino acid of the cell-wall peptidoglycan was meso-diaminopimelic acid(meso-DAP).MK-7 was the predominant quinones.Major polar lipids were diphosphatidyl glycerol DPG,PG,PE and PME.On the basis of the polyphasic evidence presented,strain FJAT-46582T was considered to represent a novel member of the genus Bacillus,for which the name Bacillus xiapuensis sp.nov.is proposed.The type strain was FJAT-46582T(=CCTCC AB 201747T).