Kim Wonduck, Major Tiffany A, Whitman William B
Department of Microbiology, The Ohio State University, Columbus, OH, USA.
Archaea. 2005 Dec;1(6):375-84. doi: 10.1155/2005/903614.
In Methanococcus maripaludis strain JJ, deletion of the homolog to cbiJ, which encodes the corrin biosynthetic enzyme precorrin 6-X reductase, yielded an auxotroph that required either cobamide or acetate for good growth. This phenotype closely resembled that of JJ117, a mutant in which tandem repeats were introduced into the region immediately downstream of the homolog of cbiJ. Mutant JJ117 also produced low quantities of cobamides, about 15 nmol g(-1) protein or 1-2% of the amount found in wild-type cells. These results confirm the role of the cbiJ homolog in cobamide biosynthesis in the Archaea and suggest the presence of low amounts of a bypass activity in these organisms.
在马氏甲烷球菌菌株JJ中，编码钴胺素生物合成酶前咕啉6-X还原酶的cbiJ同源物缺失，产生了一种营养缺陷型菌株，该菌株需要钴胺酰胺或乙酸盐才能良好生长。这种表型与JJ117非常相似，JJ117是一种突变体，其中在cbiJ同源物下游紧邻区域引入了串联重复序列。突变体JJ117也产生少量的钴胺酰胺，约15 nmol g(-1)蛋白质，或野生型细胞中发现量的1-2%。这些结果证实了cbiJ同源物在古菌钴胺酰胺生物合成中的作用，并表明这些生物体中存在少量的旁路活性。
