Barlow T
Karolinska Institute, Stockholm, Sweden.
Biochem Biophys Res Commun. 1988 Sep 15;155(2):747-53. doi: 10.1016/s0006-291x(88)80558-8.
E. coli conditional iron-containing ribonucleotide reductase (Fe-RR) mutant and wild type strains grew anaerobically under conditions when Fe-RR was absent or inhibited. Furthermore, a B12-independent, hydroxyurea-resistant RR activity, unaffected by monoclonal antibodies against either subunit B1 or B2 of Fe-RR, was partially purified from anaerobically grown mutant and wild-type E. coli. These findings indicate that E. coli has a second RR representative of a new class of RRs and that this is the first report where both in vivo and in vitro evidence is presented. It is probable that other facultative anaerobes also have two different RRs such that an optimal supply of deoxyribonucleotides is maintained under all growth conditions.
大肠杆菌含铁核糖核苷酸还原酶（Fe-RR）条件性突变体和野生型菌株在Fe-RR缺失或受抑制的条件下厌氧生长。此外，从厌氧生长的突变体和野生型大肠杆菌中部分纯化出了一种不依赖维生素B12、耐羟基脲的RR活性，该活性不受针对Fe-RR亚基B1或B2的单克隆抗体的影响。这些发现表明，大肠杆菌有一种代表新型RR的第二种RR，这是首次同时提供体内和体外证据的报告。其他兼性厌氧菌很可能也有两种不同的RR，以便在所有生长条件下维持脱氧核糖核苷酸的最佳供应。
