Chen Liang, Dong Chunming, He Jin, Shao Zongze
College of Life Science and Technology, State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China.
Wei Sheng Wu Xue Bao. 2010 Oct;50(10):1392-8.
The aim of this study is to assess the diversity of polycyclic aromatic carbon (PAH)-degrading bacteria in the coastal seawater of Xiamen Island.
The phenanthrene-degrading bacteria were enriched by suspending phenanthrene-coated Polyvinylchloride (PVC) plates in the seawater close to Xiamen International Cruise Dock. PCR-DGGE and 16S rRNA gene clone library were used to analyze the bacteria colonizing on the PVC plates. Further, PAH-degrading bacteria were re-enriched in lab after the in situ enrichment and subjected to diversity analysis and bacterial isolation.
After 6 days incubation, the genus Cycloclasticus was shown to be the dominant bacterium on the phenanthrene (Phe)-coated plates, which accounted for 50% of the total clones in 16S rRNA gene clone library. However, on the control plates without Phe-coating, bacteria of Rhodobacteraceae were the dominant member, which accounted for 47% of the total clones. PCR-DGGE results reconfirmed the genus Cycloclasticus as the dominant member on the Phe-coated plates. After re-enrichment with Phe in laboratory, 14 strains were isolated from the consortium, which contained a potential novel species of genus Novosphingobium, named strain B-14 and identified as a Phe degrader. However, the most predominant member Cycloclasticus can not be cultivated into pure culture.
Genus Cycloclasticus is the most important PAH-degrading bacterium in the coast sea water of Xiamen Island. This is the first evidence to our knowledge about the in situ enrichment PAH-degrading bacterium in seawater.
本研究旨在评估厦门岛近岸海水中多环芳烃碳（PAH）降解菌的多样性。
将涂有菲的聚氯乙烯（PVC）平板悬浮于厦门国际邮轮码头附近的海水中，富集菲降解菌。采用PCR-DGGE和16S rRNA基因克隆文库分析定殖在PVC平板上的细菌。此外，原位富集后的PAH降解菌在实验室中再次富集，进行多样性分析和细菌分离。
培养6天后，环裂菌属在涂有菲（Phe）的平板上为优势菌，在16S rRNA基因克隆文库中占总克隆数的50%。然而，在未涂Phe的对照平板上，红杆菌科细菌为优势成员，占总克隆数的47%。PCR-DGGE结果再次证实环裂菌属是涂有Phe平板上的优势成员。在实验室用Phe再次富集后，从该菌群中分离出14株菌，其中包含一种潜在的新鞘氨醇菌属新物种，命名为菌株B-14，并鉴定为菲降解菌。然而，最主要的成员环裂菌属无法培养成纯培养物。
环裂菌属是厦门岛近岸海水中最重要的PAH降解菌。据我们所知，这是关于海水中原位富集PAH降解菌的首个证据。
