Succinlc Acid Production Y Rumen Bacteria I. Isolation and Metabolism of Ruminococcus Flavefaciens

Abstract

A strain of R. flavefaciens was isolated from the sheep rumen. Succinic acid was a major end� product of glucose fermentation by this organism when C02 was freely available, but in the absence of C02, the fermentation was nearly homolactic. The products of pyruvate fermentation were consistent with the proposition that pyruvate is an intermediate in the fermentation of glucose. Possible routes of the fermentation are discussed in the light of these findings.

Effects of Carbon Dioxide on Growth and Maltose Fermentation by Bacteroides amylophilus

“…brevis strain GA33, and during cellobiose fermentation by B. succinogenes strain S85, provide direct evidence for reactions involving carbon dioxide fixation in succinate formation by rumen Bacteroides species. The present results, combined with previous studies showing the incorporation of label from 4CO2 into the succinate formed during glucose fermentation by R. flavefaciens (19,20) and by S. dextrinosolvens (27,28), indicate that reactions involving the fixation of label from "CO2 into the succinate are commonly found among succinogenic rumen bacteria.…”

“…Direct evidence for the involvement of carbon dioxide in formation of succinate by ruminal bacteria was subsequently obtained by Scardovi (27), who showed nearly stoichiometric incorporation of label from carbon dioxide into the succinate produced during glucose fermentation by Succinivibrio dextrinosolvens. Recent work of Hopgood and Walker (19,20) has shown the incorporation of label from carbon dioxide into the carboxyl carbon of the succinate produced by an organism similar to Ruminococcus flavefaciens. Since many rumen bacteria produce succinate as a major fermentation end product, study of the mechanisms of succinate formation by these organisms should contribute to knowledge of ruminal carbohydrate fermentation, of energy metabolism of anaerobic bacteria, and carbon dioxide metabolism.…”

Polysaccharide synthesis and degradation by rumen micro-organismsin vitro

“…The carbohydrates tested as precursors of starch (Table 1) have been found by other workers to be readily fermented in vitro and glucosans may be formed, although not by every organism which utilizes the sugar (Butterworth, Bell & Garvock, 1960;Doetsch et al 1953;McNaught, 1951;Howard, 1955;Bryant, Small, Bouma & Robinson, 1958;Hungate, 1963;Hopgood & Walker, 1967).…”

Influence of CO 2 -HCO 3 − Levels and pH on Growth, Succinate Production, and Enzyme Activities of Anaerobiospirillum succiniciproducens

“…Although many different kinds of bacteria (e.g., Escherichia coli, Bacteroidesfragilis, and Wolinella succinogenes, etc.) produce succinate as an anaerobic end product, few species that make it as the major end product in high concentration are reported (8,13,23,24,26,27). In gastrointestinal tracts such as the rumen, high levels of CO2 are formed and the natural microbial flora (e.g., Ruminococcus flavofaciens and Bacteroides succinogenes) produces succinic acid as a major end product of carbohydrate degradation (8,9,24).…”