Previous Article | Next Article ![]()
Appl Environ Microbiol, March 1998, p. 1066-1069, Vol. 64, No. 3
Woods Hole Oceanographic Institution, Woods
Hole, Massachusetts 02543
Received 16 October 1997/Accepted 7 January 1998
Species of the widespread marine prokaryote
Prochlorococcus exhibited ultradian growth (faster than 1 division per day) both in situ and in culture, even though cell
division is strictly phased to the light-dark cycle. Under optimal
conditions a second DNA replication and cell division closely followed,
but did not overlap with, the first division. The timing of cell cycle
events was not affected by light intensity or duration, suggesting
control by a light-triggered timer or circadian clock rather than by
completion of a light-dependent assimilation phase. This mode of
ultradian growth has not been observed previously and poses new
questions about the regulation of cellular rhythms in prokaryotes. In
addition, it implies that conclusions regarding the lack of nutrient
limitation of Prochlorococcus in the open ocean, which were
based on the appearance that cells were growing at their maximal rate,
need to be reconsidered.
0099-2240/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Ultradian Growth in
Prochlorococcus spp.
*
Corresponding author. Mailing address: Biology
Department, MS #32, Woods Hole Oceanographic Institution, Woods Hole,
MA 02543. Phone: (508) 289-2565. Fax: (508) 457-2169. E-mail:
rolson{at}whoi.edu.
This article has been cited by other articles:
| J. Bacteriol. | Microbiol. Mol. Biol. Rev. | Eukaryot. Cell | All ASM Journals |
|---|