Genetic Confirmation of the Role of Sulfopyruvate Decarboxylase in Coenzyme M Biosynthesis inMethanococcus maripaludis

[摘要] Coenzyme M is an essential coenzyme for methanogenesis. The proposed biosynthetic pathway consists of five steps, of which the fourth step is catalyzed by sulfopyruvate decarboxylase (ComDE). Disruption of the genecomEby transposon mutagenesis resulted in a partial coenzyme M auxotroph, which grew poorly in the absence of coenzyme M and retained less than 3% of the wild type level of coenzyme M biosynthesis. Upon coenzyme M addition, normal growth of the mutant was restored. Moreover, complementation of the mutation with the wild typecomEgene intransrestored full growth in the absence of coenzyme M. These results confirm that ComE plays an important role in coenzyme M biosynthesis. The inability to yield a complete CoM auxotroph suggests that either the transposon insertion failed to completely inactivate the gene orM. maripaludispossesses a promiscuous activity that partially complemented the mutation.

[学科分类] 微生物学和免疫学