Laboratory of Microbial Ecology, Division of Applied Sciences, Harvard University, Cambridge, Massachusetts 02138.
Appl Environ Microbiol. 1985 Nov;50(5):1244-50. doi: 10.1128/aem.50.5.1244-1250.1985.
Butyrate is an important intermediate in the anaerobic degradation of organic matter. In sulfate-depleted environments butyrate is oxidized to acetate and hydrogen by obligate proton reducers, in syntrophic association with hydrogen-consuming methanogens. This paper describes two enrichments of endospore-forming bacteria degrading butyrate in consortia with methanogens. The isolates are readily established in coculture with H(2)-consuming, sulfate-reducing bacteria by pasteurizing the culture. The two original enrichments differed in that one grew to an optically dense culture while the second grew in clumps. Examination by scanning electron microscopy showed that clumping resulted from the production of large amounts of extracellular polymer. Several H(2)-consuming methanogens were identified in the enrichments. Some of them grew closely associated to the butyrate degraders. This attachment to the hydrogen producer may permit some methanogens to compete for the growth substrate against other bacteria having higher substrate affinity.
丁酸盐是有机物质厌氧降解的重要中间产物。在硫酸盐耗尽的环境中，丁酸盐被专性产氢还原菌氧化为乙酸盐和氢气，与消耗氢气的产甲烷菌形成共生关系。本文描述了两种富集能够与产甲烷菌形成共生体降解丁酸盐的内生孢子形成细菌的方法。通过巴氏灭菌培养物，这些分离物可以很容易地与消耗氢气的硫酸盐还原菌共培养。这两个原始的富集物有区别，一个在光学上生长到密集培养物，而另一个则成团生长。扫描电子显微镜检查表明，成团生长是由于产生了大量的胞外聚合物。在富集物中鉴定出了几种消耗氢气的产甲烷菌。其中一些与丁酸降解菌密切相关。这种与产氢菌的附着可能使一些产甲烷菌能够与其他具有更高底物亲和力的细菌竞争生长基质。
