德夯嗜盐耐盐菌抗菌活性筛选和系统发育

Screening and Phylogenetic Analysis of Antibiotic-Producing Halophilic and Halotolerant Bacteria from the Dehang Canyon in Hunan China

以8个敏感菌株作为指示菌,采用琼脂扩散法,对分离自湖南省德夯峡谷（28°15′~28°43′N,109°30′~109°45′E）普通非盐环境土壤样品中的294株嗜盐及耐盐细菌进行抗菌活性筛选,并对其中具有较强抗菌活性的菌株进行基于16S rRNA基因序列的系统发育分析.受试菌株中有109株的发酵产物具有抗菌活性（阳性率37.1%）,其中5个菌株具有较强抗菌活性（JSM 102030,JSM 102052,JSM 102054,JSM 102066,JSM 102082）.基于16SrRNA基因序列的系统发育分析表明,这5个菌株分别属于细菌域（Eubacteria）的3个门（Actinobacteria,Firmicutes,Proteobacteria）中的3个科（Bacillaceae,Halomonadaceae,Nocardiopsaceae）的4个属,菌株JSM 102030属于Halobacillus属,与该属已知种Halobacillus trueperi DSM 10404T的系统发育关系最为密切（序列相似性为99.1%）,JSM 102052和JSM 102054属于Halomonas属,与Halomonas alkaliphila 18bAGT的系统发育关系最为密切（序列相似性为98.3%）,JSM 102066属于Nocardiopsis属,与其系统发育关系最为密切的是Nocardiopsis prasina DSM43845T（序列相似性为99.3%）,JSM 102082与Oceanobacillus属的Oceanobacillus kimchii X50T以99.6%的16SrRNA基因序列相似性聚在一起.研究结果表明,分离自湖南省德夯峡谷普通非盐环境土样的嗜盐及耐盐细菌中存在较高比例的抗菌活性菌株,且这些细菌具有较为丰富的系统发育多样性.

The antimicrobial activity of the fermentation brothes of 294 halophilic and halotolerant bacteria,isolated from ordinary non-saline soils collected from the Dehang Canyon（28°15′~28°43′N,109°30′~109°45′E）in Hunan Province,China,was screened using the agar diffusion method employing 8 indicator microorganisms（three Gram-positive bacteria,three Gram-negative bacteria and two fungi）.The results showed that,out of 294 strains tested,109 were positive in antimicrobial activity（37.1%）,in which 5 strains exhibited strong antimicrobial activity.Then these 5strains were submitted for 16 SrRNA gene amplification and phylogenetic analysis after phenotypic characterization including morphological,biochemical and physiological tests.The results suggested that these 5strains were members of 4genera in3families（Bacillaceae,Halomonadaceae,Nocardiopsaceae）of 3 phyla（Actinobacteria,Firmicutes,Proteobacteria）：strain JSM 102030 belonged to the genus Halobacillus（Firmicutes,Bacillaceae）,being most closely to the type strain of Halobacillus trueperi（sequence similarity 99.1%）;strains 102052 and JSM 102054 were members of the genus Halomonas（Proteobacteria,Halomonadaceae）,being related most closely to the type strain of Halomonas alkaliphila（98.3%）;strains JSM 102066 strain JSM2155017 belonged to the genus Nocardiopsis（Actinobacteria,Nocardiopsaceae）,exhibiting 99.3 % 16 S rRNA gene sequence similarity to Nocardiopsis prasina DSM43845T;strain JSM 102082 belonged to the genus Oceanobacillus（Firmicutes,Bacillaceae）,exhibiting 99.6% 16 SrRNA gene sequence similarity to Oceanobacillus kimchii X50 T.