Wang Wanpeng, Zhang Rongqiu, Shan Dapeng, Shao Zongze
Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, SOA, 361005, Xiamen, China.
Appl Microbiol Biotechnol. 2014 Aug;98(16):7253-69. doi: 10.1007/s00253-014-5817-1. Epub 2014 May 28.
Indigenous oil-degrading bacteria play an important role in efficient remediation of polluted marine environments. In this study, we investigated the diversity and abundance of indigenous oil-degrading bacteria and functional genes in crude oil-contaminated seawater of the Dalian coast. The gene copy number bacterial 16S rRNA in total were determined to be about 10(10) copies L(-1) in contaminated seawater and 10(9) copies L(-1) in uncontaminated seawater. Bacteria of Alcanivorax, Marinobacter, Novosphingobium, Rhodococcus, and Pseudoalteromonas were found to be predominant oil-degrading bacteria in the polluted seawater in situ. In addition, bacteria belonging to Algoriphagus, Aestuariibacter, Celeribacter, Fabibacter, Zobellia, Tenacibaculum, Citreicella, Roseivirga, Winogradskyella, Thioclava, Polaribacter, and Pelagibaca were confirmed to be the first time as an oil-degrading bacterium. The indigenous functional enzymes, including AlkB or polycyclic aromatic hydrocarbons ring-hydroxylating dioxygenases α (PAH-RHDα) coding genes from Gram-positive (GP) and Gram-negative bacteria (GN), were revealed and quite diverse. About 10(10) to 10(11) copies L(-1) for the expression of alkB genes were recovered and showed that the two-thirds of all the AlkB sequences were closely related to widely distributed Alcanivorax and Marinobacter isolates. About 10(9) copies L(-1) seawater for the expression of RHDαGN genes in contaminated seawater and showed that almost all RHDαGN sequences were closely related to an uncultured bacterium; however, RHDαGP genes represented only about 10(5) copies L(-1) seawater for the expression of genes in contaminated seawater, and the naphthalene dioxygenase sequences from Rhodococcus and Mycobacterium species were most abundant. Together, their data provide evidence that there exists an active aerobic microbial community indigenous to the coastal area of the Yellow sea that is capable of degrading petroleum hydrocarbons.
本土石油降解细菌在受污染海洋环境的高效修复中发挥着重要作用。在本研究中，我们调查了大连沿海原油污染海水中本土石油降解细菌和功能基因的多样性与丰度。测定受污染海水中细菌16S rRNA的基因拷贝数总量约为10¹⁰拷贝/L，未受污染海水中为10⁹拷贝/L。原位受污染海水中，食烷菌属、海杆菌属、新鞘氨醇菌属、红球菌属和假交替单胞菌属的细菌被发现是主要的石油降解细菌。此外，噬藻体菌属、河口杆菌属、敏捷杆菌属、费氏菌属、噬琼胶菌属、黄杆菌属、柠檬色菌属、玫瑰弧菌属、维诺格拉德斯基氏菌属、硫棒菌属、极地杆菌属和大洋杆菌属的细菌首次被确认为石油降解细菌。揭示了包括革兰氏阳性菌（GP）和革兰氏阴性菌（GN）的AlkB或多环芳烃环羟基化双加氧酶α（PAH-RHDα）编码基因在内的本土功能酶，且种类繁多。回收得到约10¹⁰至10¹¹拷贝/L的alkB基因表达量，表明所有AlkB序列中有三分之二与广泛分布的食烷菌属和海杆菌属分离株密切相关。受污染海水中RHDαGN基因的表达量约为10⁹拷贝/L海水，表明几乎所有RHDαGN序列都与一种未培养细菌密切相关；然而，RHDαGP基因在受污染海水中的基因表达量仅约为10⁵拷贝/L海水，红球菌属和分枝杆菌属的萘双加氧酶序列最为丰富。总之，他们的数据提供了证据，表明黄海沿海地区存在一个活跃的能降解石油烃的本土需氧微生物群落。
