Gray Freshwater Biological Institute, University of Minnesota, Navarre, Minnesota 55392.
Appl Environ Microbiol. 1989 Dec;55(12):3124-30. doi: 10.1128/aem.55.12.3124-3130.1989.
Restriction maps of genes required for the synthesis of active methanol dehydrogenase in Methylobacterium organophilum XX and Methylobacterium sp. strain AM1 have been completed and compared. In these two species of pink-pigmented, type II methylotrophs, 15 genes were identified that were required for the expression of methanol dehydrogenase activity. None of these genes were required for the synthesis of the prosthetic group of methanol dehydrogenase, pyrroloquinoline quinone. The structural gene required for the synthesis of cytochrome c(L), an electron acceptor uniquely required for methanol dehydrogenase, and the genes encoding small basic peptides that copurified with methanol dehydrogenases were closely linked to the methanol dehydrogenase structural genes. A cloned 22-kilobase DNA insert from Methylsporovibrio methanica 81Z, an obligate type II methanotroph, complemented mutants that contained lesions in four genes closely linked to the methanol dehydrogenase structural genes. The methanol dehydrogenase and cytochrome c(L) structural genes were found to be transcribed independently in M. organophilum XX. Only two of the genes required for methanol dehydrogenase synthesis in this bacterium were found to be cotranscribed.
粉红着色的、Ⅱ型甲醇营养菌甲基杆菌 XX 和甲基杆菌 AM1 中合成活性甲醇脱氢酶所需基因的限制图谱已经完成并进行了比较。在这两个种属的细菌中，有 15 个基因被鉴定为甲醇脱氢酶活性表达所必需。这些基因都不参与合成甲醇脱氢酶的辅基吡咯喹啉醌。合成细胞色素 c(L)（甲醇脱氢酶唯一需要的电子受体）的结构基因，以及与甲醇脱氢酶共纯化的编码小碱性肽的基因，与甲醇脱氢酶结构基因紧密连锁。来自专性Ⅱ型甲烷营养菌 Methanospirillum methanica 81Z 的克隆的 22 千碱基对的 DNA 插入片段，可补充与甲醇脱氢酶结构基因紧密连锁的四个基因中有缺陷的突变体。在甲基杆菌 XX 中发现甲醇脱氢酶和细胞色素 c(L)结构基因独立转录。在这种细菌中，有两个合成甲醇脱氢酶所需的基因被发现共转录。
