为了研究虾池沉积物细菌的多样性,改进培养技术,采用8种培养基培养虾池沉积物细菌,并用变性梯度凝胶电泳(DGGE)技术对不同培养基平板获得的细菌群落结构进行研究,同时与原位样品的细菌群落结构进行比较.多数细菌在2周内长出,第3周至12周,在VL55、DNB、HM2和DR2A平板上可分离出新的细菌,其他培养基平板上的菌落数目增长不明显.分别使用琼脂和结冷胶作为凝胶剂,结果发现,结冷胶平板和琼脂平板相比,表现出高保湿性、高菌落数和高细菌多样性的特点.变性梯度凝胶电泳(DGGE)分析结果表明,沉积物样品中的优势细菌约60种,经过不同培养基培养后,得到的细菌多样性为50种左右,约为原来总数的83%,但是细菌群落结构发生较大改变,优势菌群发生转化.测序结果证明了这一点.虾池沉积物中有着较高的细菌多样性.培养基的改进、结冷胶的使用和培养时间的延长有效提高了虾池沉积物中细菌的可培养性.
To study bacterial diversity of shrimp pond sediment and improve culture technique,8 kinds of media were used to isolate bacteria from shrimp pond sediment.Bacterial colonies were collected and denaturing gradient gel electrophoresis(DGGE) technique was used to study the bacterial community structure and it was compared with that of in situ sample.Most of bacteria appeared in the first 2 weeks.During the 3rd week and the 12 th week,there were some new isolates on VL55,DNB,HM2 and DR2A plates,and the colony number was no obviously increasing on other plates.Agar and gellan gum were used as gelling agent separately,the culture results showed that gellan gum plates had a high moisture retention,more bacterial number and high bacterial diversity than that on agar plates.By the analysis of DGGE profile,there were about 60 kinds of bacterial strains in the sediment.Cultured by the media,about 50 kinds of bacterial strains were detected.The number of it was up to 83% of that of the sediment.However,the bacterial community structure had a great variation and the dominant microorganisms changed.It was confirmed by sequencing results too.There were high bacterial diversity in the shrimp pond sediment.Improvement of medium,using of gellan gum and prolongation of culture time effectively obtained the culturability of the shrimp pond sediment.