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A CIRCADIAN RHYTHM IN CELL DIVISION IN A PROKARYOTE, THE CYANOBACTERIUM SYNECHOCOCCUS WH78031
Article first published online: 29 OCT 2004
Journal of Phycology
Volume 25, Issue 1, pages 183–186, March 1989
How to Cite
Sweeney, B. M. and Borgese, M. B. (1989), A CIRCADIAN RHYTHM IN CELL DIVISION IN A PROKARYOTE, THE CYANOBACTERIUM SYNECHOCOCCUS WH7803. Journal of Phycology, 25: 183–186. doi: 10.1111/j.0022-3646.1989.00183.x
Received 25 July 1988. Accepted 19 September 1988.
This research was supported by Grant No. PCM83 14314 from the National Science Foundation. We are grateful to Prof. Barbara B. Prézelin for supplying us with a culture of Synechococcus strain WH7803.
- Issue published online: 29 OCT 2004
- Article first published online: 29 OCT 2004
- cell division rhythm;
- circadian clock;
- Synechococcus WH7803;
- temperature compensation
Circadian rhythms are common in eukaryotes, but the several claimed cases in prokaryotes are all open to alternative interpretation. We report here a clearcut circadian rhythm in cell division in a marine Synechococcus sp. strain WH7803, under conditions where the generation time is longer than one day, that is entrained by a light–dark cycle, and that persists for at least four cycles in continuous light (2 μE·m−2·s−1) and constant temperature (22, 20 or 16°C) with a maximum in dividing cells at about 24 h intervals. Thus, the prokaryote, Synechococcus, satisfies the criteria for the possession of a true temperature-compensated circadian clock. Were the existence of such a rhythm confirmed, current hypotheses that intracellular compartments are required for circadian timing may require modification.