Bacteroids synthesize nitrogenase, a Mo-Fe protein, which is the enzyme that catalyzes reduction of N2 to ammonia. 类菌体合成固氮酶，一种钼铁蛋白，这种酶能催化氮气还原为氨。
These results indicate that the decrease of nitrogenase activity of nodules under the boron-deficiency stress was not due to carbohydratedeficiency. 这说明了在缺硼条件下，根瘤固氮酶活性的下降并不是由于碳水化合物供应不足所造成的。
