Under continuous illumination this unicellular aerobic cyanobacterium fixes dinitrogen continuously at a variable and usually low rate. Exposure of the culture to diurnal light/dark cycles invariably results in the virtual restriction of nitrogenase activity to the dark periods. The rhythmic diurnal dinitrogen fixation pattern becomes a truely endogenous cycle which persists for at least 4 days with decreasing magnitude on exposing the culture to continuous illumination. The free running time of the rhythm appears to decrease from an initial 26 h to 22 h in the course of 4 days. This appears to be the first record of an endogenous rhythm in a prokaryote.
|頁（從 - 到）||173-177|
|期刊||FEMS Microbiology Letters|
|出版狀態||已發佈 - 1月 1 1986|
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