胶州湾沉积物可培养细菌的多样性及其抑菌活性

Diversity and antimicrobial activities of cultivable bacteria isolated from Jiaozhou Bay

摘要:

[目的] 海洋微生物在活性物质开发方面具有巨大的应用前景。为了研究胶州湾微生物的多样性和抑菌活性，选取胶州湾9个观测站点的沉积物进行了细菌多样性及抑菌活性分析。[方法] 采用YPD和Z2216E培养基分离细菌，通过16S rRNA基因测序对分离菌株进行分类鉴定，继而采用牛津杯法考察分离菌株对7株指示菌的抑菌活性，最后用PCR方法筛选16株代表菌的PKSI、NRPS、CYP、PhzE和dTGD基因。[结果] 从胶州湾沉积物中共分离出76株细菌，通过对16S rRNA序列分析，将其归为8个科11个属：节杆菌属、考克氏菌属、微球菌属、微杆菌属、假交替单胞菌属、Oceanisphaera、海单胞菌属、葡萄球菌属、芽孢杆菌属、硫胺素芽孢杆菌属和短芽孢杆菌属，其中分离细菌中有34株至少对1种指示菌有抑菌活性。所选取的16株菌均能检测到一种功能基因，且其中5株菌能同时检测到3种以上的功能基因。[结论] 以上研究表明胶州湾海域有丰富的微生物资源，在生物活性次级代谢产物合成上有较大潜力。

关键词:细菌;抑菌活性;功能基因;胶州湾

Abstract:

[Objective] Marine microorganisms have a great potential in producing biologically active secondary metabolites. In order to study the diversity and antimicrobial activity, we explored 9 sediment samples in different observation sites of Jiaozhou bay.[Methods] We used YPD and Z2216E culture medium to isolate bacteria from the sediments; 16S rRNA was sequenced for classification and identification of the isolates. Then, we used Oxford cup method to detect antimicrobial activities of the isolated bacteria against 7 test strains. Lastly, we selected 16 representatives to detect secondary-metabolite biosynthesis genes:PKSI, NRPS, CYP, PhzE, dTGD by PCR specific amplification.[Results] A total of 76 bacterial strains were isolated from Jiaozhou bay; according to the 16S rRNA gene sequence analysis. These strains could be sorted into 11 genera belonging to 8 different families:Aneurinibacillus, Brevibacillus, Microbacterium, Oceanisphae, Bacillus, Marinomonas, Staphylococcus, Kocuria, Arthrobacters, Micrococcus and Pseudoalteromonas. Of them 34 strains showed antimicrobial activity against at least one of the tested strains. All 16 strains had at least one function genes, 5 strains possessed more than three function genes.[Conclusion] Jiaozhou bay area is rich in microbial resources with potential in providing useful secondary metabolites.

Key words:bacteria;antimicrobial activity;functional genes;Jiaozhou Bay