Cui Jing, Zhao Ji, Wang Zheng, Cao Weiwei, Zhang Shaohua, Liu Jumei, Bao Zhihua
School of Life Sciences, Inner Mongolia University, Hohhot, 010070, China.
Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau & Inner Mongolia Key Laboratory of Grassland Ecology, School of Ecology and Environment, Inner Mongolia University, 235 West University Street, Hohhot, 010021, China.
AMB Express. 2020 Mar 14;10(1):48. doi: 10.1186/s13568-020-00984-x.
Root-associated aerobic methanotrophs play an important role in regulating methane emissions from the wetlands. However, the influences of the plant genotype on root-associated methanotrophic structures, especially on active flora, remain poorly understood. Transcription of the pmoA gene, encoding particulate methane monooxygenase in methanotrophs, was analyzed by reverse transcription PCR (RT-PCR) of mRNA isolated from root samples of three emergent macrophytes, including Phragmites australis, Typha angustifolia, and Schoenoplectus triqueter (syn. Scirpus triqueter L.) from a eutrophic wetland. High-throughput sequencing of pmoA based on DNA and cDNA was used to analyze the methanotrophic community. Sequencing of cDNA pmoA amplicons confirmed that the structure of active methanotrophic was not always consistent with DNA. A type I methanotroph, Methylomonas, was the most active group in P. australis, whereas Methylocystis, a type II methanotroph, was the dominant group in S. triqueter. In T. angustifolia, these two types of methanotroph existed in similar proportions. However, at the DNA level, Methylomonas was predominant in the roots of all three plants. In addition, vegetation type could have a profound impact on root-associated methanotrophic community at both DNA and cDNA levels. These results indicate that members of the genera Methylomonas (type I) and Methylocystis (type II) can significantly contribute to aerobic methane oxidation in a eutrophic wetland.
与根系相关的好氧甲烷氧化菌在调节湿地甲烷排放方面发挥着重要作用。然而，植物基因型对与根系相关的甲烷营养结构，尤其是对活跃菌群的影响仍知之甚少。通过对从一个富营养化湿地采集的三种挺水大型植物（包括芦苇、香蒲和三棱藨草）根系样本中分离的mRNA进行逆转录PCR（RT-PCR），分析了甲烷氧化菌中编码颗粒甲烷单加氧酶的pmoA基因的转录情况。基于DNA和cDNA的pmoA高通量测序用于分析甲烷营养群落。cDNA pmoA扩增子测序证实，活跃甲烷营养菌的结构并不总是与DNA一致。I型甲烷氧化菌甲基单胞菌属是芦苇中最活跃的菌群，而II型甲烷氧化菌甲基孢囊菌属是三棱藨草中的优势菌群。在香蒲中，这两种类型的甲烷氧化菌比例相似。然而，在DNA水平上，甲基单胞菌属在所有三种植物的根系中都占主导地位。此外，植被类型在DNA和cDNA水平上都可能对与根系相关的甲烷营养群落产生深远影响。这些结果表明，甲基单胞菌属（I型）和甲基孢囊菌属（II型）的成员对富营养化湿地中的好氧甲烷氧化有显著贡献。
