抗分枝杆菌海洋微生物的分离与鉴定

Isolation and identification of marine bacteria with bacteriostasis to Mycobacterium smegmatis MC;155

目的从海洋微生物中发现具有抗分枝杆菌活性的细菌,并对其进行鉴定。方法从印度洋热带地区的海底沉积物中分离海洋微生物。通过纸片法活性测定,发现了一株具有抗耻垢分枝杆菌活性的细菌。光学显微下观察细菌形态和菌落。测定细菌的理化特性,提取其基因组,荧光法测定基因组的T_(m)值,扩增其16S rDNA并进行测序。将序列提交NCBI和EzTaxon网站进行搜索比对,使用MEGA 7.0软件构建系统进化树。结果分离得到的菌株IMBGY10-46的发酵产物具有抗耻垢分枝杆菌活性;其与Pseudomonas sabulinigriJ64的16S rDNA相似性最高,但菌体形态和基因组的Tm值相差较大,并且过氧化氢酶试验呈阴性。将该菌株命名为假单胞菌属新菌株。该细菌的16S rDNA序列提交GenBank,收录号为JQ362457。结论从海底沉积物中获得了具有抗耻垢分枝杆菌作用的海洋微生物新菌株。

Objective We aim to identify novel anti-mycobacterial microorganisms from marine microbes.Methods Marine microorganisms were separated from the samples of seafloor sediments from the Indian Ocean tropical region. A paper disk method was used to determine the anti-mycobacteria activity, whereas light microscopy was utilized to learn the morphologies of bacteria and colony. The physicochemical properties of IMBGY10-46 were measured. The genome of IMBGY10-46 was extracted by genomic purification kit. In addition, fluorescence spectrometry was harnessed to determine the T_(m) value of bacterial genome. 16 S rDNA was amplified by PCR and its sequence was subjected to BLAST in NCBI and EzTaxon. A phylogenetic tree was built by MEGA 7.0.Results Anti-mycobacterial activity was discovered in the fermentative liquid of IMBGY10-46, whose 16 S rDNA had the highest homology with that of Pseudomonas sabulinigri J64. Nevertheless, there were diverse in morphology and in Tm value of genome.The strain IMBGY10-46 was found to be catalase-negative. To this end, the 16 S rDNA sequence of IMBGY10-46 was deposited in GenBank(Accession No. JQ362457).Conclusion A new marina bacteria isolated from the seafloor sediment can produce secondary metabolites against Mycobacterium smegmatis.