Fletcher A J, Pugsley A P, Glass R E
J Gen Microbiol. 1986 Sep;132(9):2643-6. doi: 10.1099/00221287-132-9-2643.
Operon fusions were isolated between Mu dX (lac CmR ApR) and btuB, the gene encoding the multivalent vitamin B12 outer membrane receptor. Using these fusions, vitamin B12-mediated repression of btuB in Escherichia coli was demonstrated. Mutations in metH, metE and ompR as well as exogenous methionine, membrane pertubants, high osmolar conditions and temperature had no major effect on the expression of the btuB gene.
在Mu dX（乳糖 氯霉素抗性 氨苄青霉素抗性）与btuB（编码多价维生素B12外膜受体的基因）之间分离出操纵子融合体。利用这些融合体，证明了维生素B12对大肠杆菌中btuB基因的介导抑制作用。metH、metE和ompR的突变以及外源性甲硫氨酸、膜扰动剂、高渗条件和温度对btuB基因的表达没有重大影响。
