Cox J C
Department of Biochemistry and Molecular Biology, University of Texas, Medical School, Houston 77025.
Arch Microbiol. 1989;152(4):397-400. doi: 10.1007/BF00425180.
Four classes of Escherichia coli mutants deficient in either or both of their anaerobic selenium-containing formate dehydrogenases (FDH) were isolated. A class I mutant devoid of FDHH activity specifically linked to benzyl viologen (BV) produced a small amount of the FDHH 80,000 dalton selenopeptide. Three class II mutants were deficient in FDHN activity specifically linked to phenazine methosulfate (PMS) and exhibited a selenopeptide "doublet" rather than the FDHN 110,000 dalton selenosubunit. Three class III mutants were selenium incorporation deficient and did not exhibit either FDH activity or 75Se-labeled selenopolymers. A class IV mutant was devoid of PMS-linked FDHN activity; neither its FDHN 110,000 dalton selenosubunit nor its BV-linked FDHH activity was fully regulated by nitrate.
分离出了四类大肠杆菌突变体，它们缺乏一种或两种厌氧含硒甲酸脱氢酶（FDH）。I类突变体缺乏与苄基紫精（BV）特异性相关的FDHH活性，产生少量80,000道尔顿的硒肽FDHH。三个II类突变体缺乏与吩嗪硫酸甲酯（PMS）特异性相关的FDHN活性，并表现出硒肽“双峰”，而不是110,000道尔顿的FDHN硒亚基。三个III类突变体缺乏硒掺入能力，既不表现出FDH活性，也不表现出75Se标记的硒聚合物。IV类突变体缺乏与PMS相关的FDHN活性；其110,000道尔顿的FDHN硒亚基及其与BV相关的FDHH活性均不受硝酸盐的完全调控。
