Identification And Genome Analysis Of A Novel Bacterium Niastella Vici Sp.nov.

China is rich in mineral resource and with a lot of usage of antibiotics,consequently,heavy metal and antibiotic pollution are becoming more and more serious.Microbes have a great advantage on bioremediation of heavy metal and antibiotic pollution.Isolation and identification of microbes capable of resisting and detoxifying toxic matters are very important for bioremediation application.A total of 74 bacterial strains were isolated from farmland soil near a zinc-lead mine in Lingxiang City,Hunan Province,China.The DNA of the strains were amplified using 16 S rRNA gene primers and digested with Hae? to remove the similar strains.According to the 16 S rRNA gene sequence analysis,those strains mainly distributed within 24 species within six genus of Burkholderia,Bacillus,Lysinbacillus,Pseudomonas,Cupriavidus and Niastella.The predominant strains belonged to genus Cupriavidus come to 37.5% of the total species.Based on 16 S rRNA gene sequence analysis,one of the strains named DJ57 T was demonstrated similarities to the strains of genus Niastella,with 95.83% nucleotide identity to Niastella populi THYL-44 T,and the similarities to other type strains species of the genus Niastella were less than 95.76%,which indicated that strain DJ57 T was likely to be a novel species of the genus Niastella.This strain is a Gram-reaction-negative,filamentous-shaped,non-flagellated,aerobic bacterium.While this strain has the general characters with other Niastella strains such as the major isoprenoid quinone was menaquinone-7;the major fatty acids(> 5%)were iso-C15:0,iso-C17:0-3-OH,iso-C15:1G,anteiso-C15:0,iso-C16:0;the DNA G+C content was 44 mol%;the polar lipids were phosphatidylethanolamine,three unknown aminophospholipids,three unknown phospholipids and six unknown lipids.It also has the individual characters,for example the uniqueness of the 16 S rRNA sequence;the activity of esterase,trypsin,?-fucosidase as well as the ability for nitrification.These all indicate that strain DJ57 T represents a novel species of the genus Niastella,and is named Niastella vici sp.nov.Niastella belongs to family Chitinophagaceae of class Sphingobacteria.In order to gain knowledge and better use of the Niasstella strains,we analyzed four strains in this genus Niastella vici DJ57 T,Niastella populi 208 T,Niastella yeongjuensis 17621 T and Niastella koreensis 17620 T.It was found that they were multi-antibiotic resistance,multimetal tolerance and chitsan hydrolysis,but there was no such report in the previous study.To find out evidences from the genomic aspect,we sequenced the four strains.Genes putatively responsible for mulit-antibiotic resistance,mulit-metal tolerance and chitosan hydrolysis were found in all the four genomes.The genes related to the feature of cell,such as cell division inhibition,cell shape forming and motility were also predicted.These results indicated the correlation between phenotype and genotype of the four strains.The results of this study enriched the microbial diversity.The genomic information provided basis for theoretical and apply studies.