Huang Zhaobin, Mo Shiqing, Yan Lifei, Wei Xiaomei, Huang Yuanyuan, Zhang Lizhen, Zhang Shuhui, Liu Jianzong, Xiao Qingqing, Lin Hong, Guo Yu
College of Oceanology and Food Science, Quanzhou Normal University, Quanzhou, China.
Fujian Province Key Laboratory for the Development of Bioactive Material From Marine Algae, Quanzhou, China.
Front Microbiol. 2021 Jun 14;12:675048. doi: 10.3389/fmicb.2021.675048. eCollection 2021.
Molecular methods revealed that the majority of microbes in natural environments remains uncultivated. To fully understand the physiological and metabolic characteristics of microbes, however, culturing is still critical for microbial studies. Here, we used bacterial community analysis and four culture media, namely, traditional marine broth 2216 (MB), water extracted matter (WEM), methanol extracted matter (MEM), and starch casein agar (SCA), to investigate the diversity of cultivated bacteria in coastal sediments. A total of 1,036 isolates were obtained in pure culture, and they were classified into five groups, namely, Alphaproteobacteria (52.51%), Gammaproteobacteria (23.26%), Actinobacteria (13.32%), Firmicutes, and Bacteroidetes. Compared to other three media, WEM recovered a high diversity of actinobacteria (42 of 63 genotypes), with and as the most cultivated genera. Amplicon sequencing of the bacterial 16S ribosomal RNA (rRNA) gene V3-V4 fragment revealed eight dominant groups, Alphaproteobacteria (12.81%), Gammaproteobacteria (20.07%), Deltaproteobacteria (12.95%), Chloroflexi (13.09%), Bacteroidetes (8.28%), Actinobacteria (7.34%), Cyanobacteria (6.20%), and Acidobacteria (5.71%). The dominant members affiliated to Actinobacteria belonged to " Actinomarinales," " Microtrichales," and Nitriliruptorales. The cultivated actinobacteria accounted for a small proportion (<5%) compared to the actinobacterial community, which supported that the majority of actinobacteria are still waiting for cultivation. Our study concluded that WEM could be a useful and simple culture medium that enhanced the recovery of culturable actinobacteria from coastal sediments.
分子方法表明,自然环境中的大多数微生物仍未被培养。然而,为了全面了解微生物的生理和代谢特征,培养对于微生物研究仍然至关重要。在这里,我们使用细菌群落分析和四种培养基,即传统的海洋肉汤2216(MB)、水提取物(WEM)、甲醇提取物(MEM)和淀粉酪蛋白琼脂(SCA),来研究沿海沉积物中培养细菌的多样性。共获得1036株纯培养分离株,它们被分为五组,即α-变形菌纲(52.51%)、γ-变形菌纲(23.26%)、放线菌门(13.32%)、厚壁菌门和拟杆菌门。与其他三种培养基相比,WEM培养出了高度多样的放线菌(63个基因型中的42个),其中 和 是最常培养的属。细菌16S核糖体RNA(rRNA)基因V3-V4片段的扩增子测序揭示了八个优势菌群,α-变形菌纲(12.81%)、γ-变形菌纲(20.07%)、δ-变形菌纲(12.95%)、绿弯菌门(13.09%)、拟杆菌门(8.28%)、放线菌门(7.34%)、蓝细菌门(6.20%)和酸杆菌门(5.71%)。隶属于放线菌门的优势成员属于“海洋放线菌目”、“微丝菌目”和腈裂菌目。与放线菌群落相比,培养的放线菌占比很小(<5%),这支持了大多数放线菌仍有待培养的观点。我们的研究得出结论,WEM可能是一种有用且简单的培养基,可提高从沿海沉积物中培养可培养放线菌的回收率。