Loginova N V, Govorukhina N I, Trotsenko Iu A
Mikrobiologiia. 1982 Jan-Feb;51(1):38-42.
The object of this work was to study enzymes involved in ammonium assimilation by 15 bacterial strains of different taxonomy. The bacteria utilizing methanol and methylated amines as the sources of carbon and energy have one of the three cyclic pathways of C1-metabolism: the serine pathway, the hexulose phosphate pathway or the ribulose diphosphate pathway. The bacteria were found to differ in the enzymes for ammonium assimilation according to the pathways of primary C1-metabolism. The bacteria with the serine cycle were characterized by the reductive amination of pyruvate and the operation of the glutamate cycle (glutamine synthetases and glutamate synthases). The reductive amination of alpha-ketoglutarate is the principal pathway of ammonium nitrogen assimilation in the bacteria with the hexulose phosphate cycle. The bacteria using reduced C1-substrates autotrophically, i.e. via the ribulose diphosphate pathway, have the enzymes of the glutamate cycle, but are characterized by low activities, if any, of amino acid dehydrogenases.
这项工作的目的是研究15种不同分类学的细菌菌株中参与铵同化的酶。利用甲醇和甲基化胺作为碳源和能源的细菌具有三种C1代谢循环途径之一：丝氨酸途径、磷酸己糖途径或二磷酸核酮糖途径。根据初级C1代谢途径，发现这些细菌在铵同化酶方面存在差异。具有丝氨酸循环的细菌的特征是丙酮酸的还原胺化和谷氨酸循环（谷氨酰胺合成酶和谷氨酸合成酶）的运作。α-酮戊二酸的还原胺化是具有磷酸己糖循环的细菌中铵态氮同化的主要途径。自养利用还原型C1底物的细菌，即通过二磷酸核酮糖途径，具有谷氨酸循环的酶，但氨基酸脱氢酶的活性很低（如果有活性的话）。
