Belay N, Sparling R, Choi B S, Roberts M, Roberts J E, Daniels L
Department of Microbiology, University of Iowa, Iowa City 52242.
Biochim Biophys Acta. 1988 Oct 7;971(3):233-45. doi: 10.1016/0167-4889(88)90138-3.
Two mesophilic methanogenic bacteria, Methanobacterium bryantii strain MOH and Methanospirillum hungatei strain GP1 were demonstrated, using several different experimental approaches, to fix dinitrogen. Evidence includes (1) growth with N2 as the sole nitrogen source; (2) incorporation of 15N2 into cellular material (both soluble amino acid pools and insoluble cell protein and other macromolecules) detected by 15N-NMR spectroscopy; (3) acetylene reduction to ethylene by the cells, and inhibition of this reaction by bromoethanesulfonic acid (BES), a methanogen inhibitor. High-resolution 15N-NMR analysis of ethanol extracts of these organisms and cross-polarization magic-angle sample spinning analysis of the solid debris from these extracts are compared to labeled material from Methanococcus thermolithotrophicus, a methanogen previously determined to fix dinitrogen.
通过几种不同的实验方法证明，两种嗜温产甲烷菌，即布氏甲烷杆菌菌株MOH和亨氏甲烷螺菌菌株GP1能够固定氮气。证据包括：（1）以N₂作为唯一氮源生长；（2）通过¹⁵N-NMR光谱检测到¹⁵N₂掺入细胞物质（可溶性氨基酸池以及不溶性细胞蛋白和其他大分子）中；（3）细胞将乙炔还原为乙烯，且该反应受到产甲烷菌抑制剂溴乙烷磺酸（BES）的抑制。将这些生物体乙醇提取物的高分辨率¹⁵N-NMR分析以及这些提取物固体残渣的交叉极化魔角样品旋转分析，与先前已确定能够固定氮气的嗜热自养甲烷球菌的标记物质进行比较。
