Department of Soil and Environmental Sciences, University of California, Riverside, California 92521.
Appl Environ Microbiol. 1987 May;53(5):1168-70. doi: 10.1128/aem.53.5.1168-1170.1987.
Detached cowpea nodules that contained a nitrous oxide reductase-positive (Nor) rhizobium strain (8A55) and a nitrous oxide reductase-negative (Nor) rhizobium strain (32H1) were incubated with 1% N(2)O (95 atom% N) in the following three atmospheres: (i) aerobic with C(2)H(2) (10%), (ii) aerobic without C(2)H(2), and (iii) anaerobic (argon atmosphere) without C(2)H(2). The greatest production of N(2) occurred anaerobically with 8A55, yet very little was formed with 32H1. Although acetylene reduction activity was slightly higher with 32H1, about 10 times more N(2) was produced aerobically by 8A55 than by 32H1 in the absence of acetylene. The major reductive pathway of N(2)O reduction by denitrifying rhizobium strain 8A55 is by nitrous oxide reductase rather than nitrogenase.
从豆科植物根瘤中分离出来的、含有一氧化二氮还原酶阳性（Nor）根瘤菌（8A55）和一氧化二氮还原酶阴性（Nor）根瘤菌（32H1）的根瘤在以下三种大气条件下与 1%的 N2O（95 原子% N）孵育：（i）有氧条件下含 C2H2（10%），（ii）有氧条件下不含 C2H2，以及（iii）无氧（氩气气氛）条件下不含 C2H2。在 8A55 存在的情况下，无氧条件下产生的 N2 最多，但 32H1 产生的却很少。尽管 32H1 的乙炔还原活性略高，但在没有乙炔的情况下，8A55 有氧条件下产生的 N2 比 32H1 多约 10 倍。反硝化根瘤菌 8A55 还原 N2O 的主要还原途径是通过一氧化二氮还原酶，而不是氮酶。
