Palmquist D L, Baldwin R L
Appl Microbiol. 1966 Jan;14(1):60-9. doi: 10.1128/am.14.1.60-69.1966.
Enzymatic techniques were used to study the metabolism of carbohydrates by ruminal bacteria. A direct relationship was observed between the proportions of acetate and propionate formed and the specific activities of the enzymes which participate in forming these acids. An inverse relationship between butyrate formation and butyrate-forming enzymes was observed. The relative activities of succinic dehydrogenase to fumaric reductase, nicotinamide adenine dinucleotide-linked glutamic dehydrogenase to nicotinamide adenine dinucleotide phosphate-linked glutamic dehydrogenase, and pyridine nucleotide-nonlinked lactic dehydrogenase to pyridine nucleotide-linked lactic dehydrogenase were affected by the level of concentrates in the diet. Lactyl coenzyme A dehydrase activity was below the limits of the assay technique in many samples from the alfalfa hay diet, and increased to relatively high levels when concentrates were fed. It is suggested that the enzymatic method will prove valuable for studying the contributions of individual microorganisms to the overall ruminal metabolism, and, with certain limitations, useful for estimating the relative contributions of alternate pathways.
采用酶技术研究瘤胃细菌对碳水化合物的代谢。观察到所形成的乙酸盐和丙酸盐比例与参与形成这些酸的酶的比活性之间存在直接关系。观察到丁酸盐形成与丁酸盐形成酶之间存在反比关系。日粮中精料水平会影响琥珀酸脱氢酶与延胡索酸还原酶、烟酰胺腺嘌呤二核苷酸连接的谷氨酸脱氢酶与烟酰胺腺嘌呤二核苷酸磷酸连接的谷氨酸脱氢酶以及吡啶核苷酸非连接的乳酸脱氢酶与吡啶核苷酸连接的乳酸脱氢酶的相对活性。在许多来自苜蓿干草日粮的样本中，乳酰辅酶A脱水酶活性低于检测技术的限度，而在饲喂精料时该活性会升高到相对较高的水平。有人提出，酶法对于研究单个微生物对瘤胃整体代谢的贡献将被证明是有价值的，并且在一定限制条件下，对于估计替代途径的相对贡献也是有用的。
