Maynard R H, Premakumar R, Bishop P E
U.S. Department of Agriculture, Agriculture Research Service, Raleigh, North Carolina.
J Bacteriol. 1994 Sep;176(17):5583-6. doi: 10.1128/jb.176.17.5583-5586.1994.
Competition experiments between wild-type Azotobacter vinelandii and a mutant lacking Mo-independent nitrogenase 3 indicate that nitrogenase 3 provides an advantage during diazotrophic growth on agar media containing 100 to 500 nM Na2MoO4 but not in liquid media under the same conditions. Expression of nitrogenase 3 in wild-type cells growing on agar surfaces was verified with an anfH-lacZ fusion and by detection of nitrogenase 3 subunits. These results show that nitrogenase 3 is important for diazotrophic growth on agar medium at molybdenum concentrations that are not limiting for Mo-dependent diazotrophic growth in liquid medium.
野生型棕色固氮菌与缺乏非钼依赖型固氮酶3的突变体之间的竞争实验表明，在含有100至500 nM钼酸钠的琼脂培养基上进行固氮生长期间，固氮酶3具有优势，但在相同条件下的液体培养基中则不然。通过anfH - lacZ融合以及检测固氮酶3亚基，证实了琼脂表面生长的野生型细胞中固氮酶3的表达。这些结果表明，在钼浓度对液体培养基中依赖钼的固氮生长不产生限制的情况下，固氮酶3对于琼脂培养基上的固氮生长很重要。
