Huang T C, Chou W M
Institute of Botany, Academia Sinica, Nankang, Taipei, Taiwan 11529, Republic of China.
Plant Physiol. 1991 May;96(1):324-6. doi: 10.1104/pp.96.1.324.
The N(2)-fixing activity of the prokaryotic Synechococcus sp. RF-1 was repressed in the presence of nitrate. When the cultures in nitrate-containing medium were exposed to diurnal light-dark cycles, an endogenous circadian N(2)-fixing rhythm developed after the cells were transferred to nitrate-free medium and incubated in continuous light. The N(2)-fixing phase of the rhythm coincided with the dark phase of the light-dark cycles that were imposed when the cells were in nitrate-containing medium. The results indicate that after the endogenous N(2)-fixing rhythm has been set, it can be kept latent for at least 38 hours before first manifesting itself.
原核生物聚球藻属（Synechococcus）sp. RF-1的固氮活性在硝酸盐存在的情况下受到抑制。当在含硝酸盐的培养基中培养的细胞暴露于昼夜明暗循环时，在细胞转移至无硝酸盐培养基并在连续光照下培养后，会出现内源性昼夜固氮节律。该节律的固氮阶段与细胞处于含硝酸盐培养基时所施加的明暗循环的黑暗阶段一致。结果表明，内源性固氮节律设定后，在首次表现出来之前至少可以潜伏38小时。
