Acetate utilization as a survival strategy of peat-inhabiting Methylocystis spp.
Acetate utilization as a survival strategy of peat-inhabiting Methylocystis spp.
复制标题
DOI：
10.1111/j.1758-2229.2010.00180.x
复制
发表时间：
2011-02-01
影响因子：
3.3
通讯作者：
Dedysh, Svetlana N.
中科院分区：
文献类型：
--
作者：
Belova, Svetlana E.;Baani, Mohamed;Dedysh, Svetlana N.
传统上认为甲基孢囊菌属的代表菌是专性甲烷氧化菌，它们不能在多碳基质上生长。在这里，我们描述了一个新的属，菌株H2S，这代表了一个数字丰富的和生态上重要的甲烷氧化菌人口在北方泥炭藓为主的湿地。该分离物表现出对甲烷生长的明显偏好，但在不存在甲烷的情况下能够在乙酸盐上缓慢生长。菌株H2s具有两种形式的甲烷单加氧酶（颗粒和可溶性MMO）和发育良好的胞质膜（ICM）系统。在乙酸盐上生长几次转移的细胞中，这些ICM被维持，尽管是还原形式，并且颗粒MMO的mRNA转录物是可检测的。这些细胞在甲烷上恢复生长的速度比在没有任何底物的情况下保持相同时间的细胞更快。在乙酸盐上生长导致磷脂脂肪酸组成的重大转变。对有效描述的甲基囊藻属物种的所有模式菌株的重新检查表明，赫氏甲基囊藻H2T和棘状甲基囊藻IMET10491T也能够在乙酸盐上缓慢生长。这种能力可能是甲基孢囊菌生存策略的重要组成部分。在甲烷可用性可变或有限的环境中。
P>Representatives of the genus Methylocystis are traditionally considered to be obligately methanotrophic bacteria, which are incapable of growth on multicarbon substrates. Here, we describe a novel member of this genus, strain H2s, which represents a numerically abundant and ecologically important methanotroph population in northern Sphagnum-dominated wetlands. This isolate demonstrates a clear preference for growth on methane but is able to grow slowly on acetate in the absence of methane. Strain H2s possesses both forms of methane monooxygenase (particulate and soluble MMO) and a well-developed system of intracytoplasmic membranes (ICM). In cells grown for several transfers on acetate, these ICM are maintained, although in a reduced form, and mRNA transcripts of particulate MMO are detectable. These cells resume their growth on methane faster than those kept for the same period of time without any substrate. Growth on acetate leads to a major shift in the phospholipid fatty acid composition. The re-examination of all type strains of the validly described Methylocystis species showed that Methylocystis heyeri H2T and Methylocystis echinoides IMET10491T are also capable of slow growth on acetate. This capability might represent an important part of the survival strategy of Methylocystis spp. in environments where methane availability is variable or limited.