反刍动物瘤胃微生物利用氨合成微生物蛋白质（microbial protein，MCP）主要通过谷氨酸脱氢酶（glutamate dehydrogenase，GDH）路径和谷氨酰胺合成酶-谷氨酸合成酶复合酶系（glutamine synthetase-glutamate synthase，GS-GOGAT）路径。氨同化作用过程中的关键酶有GDH、丙氨酸脱氢酶（alanine dehydrogenase，ADH）、谷氨酰胺合成酶（GS）和谷氨酸合成酶（glutamate synthase，GOGAT）等，其活性主要受到氨浓度的影响。本文主要综述了瘤胃微生物氨同化作用过程及其关键酶。

Rumen microorganisms utilize ammonia for microbial protein (MCP) synthesis mainly through glutamate dehydrogenase (GDH) pathway and glutamine synthetase-glutamate synthase (GS-GOGAT) pathway. There are several key enzymes such as GDH, alanine dehydrogenase (ADH), GS, glutamate synthetase (GOGAT) and so on in ammonia assimilation, whose activity are affected by ammonia concentration. This article mainly reviewed the characterisation of ammonia-assimilation by microorganisms in the rumen and the key enzymes involved.［Chinese Journal of Animal Nutrition, 2010，22（5）:1171-1176］