Regulation of planktonic bacterial growth rates: The effects of temperature and resources
โ Scribed by M. Felip; M. L. Pace; J. J. Cole
- Publisher
- Springer
- Year
- 1996
- Tongue
- English
- Weight
- 849 KB
- Volume
- 31
- Category
- Article
- ISSN
- 0095-3628
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โฆ Synopsis
We examined the potential limitation of bacterial growth by temperature and nutrients in a eutrophic lake. Dilution cultures from winter and summer were incubated at both high (>20ยฐC) and low (4ยฐC) temperatures and enriched with various combinations of organic carbon (C), inorganic nitrogen (N), and inorganic phosphorus (P). Bacterial abundance, 3H-thymidine incorporation, and 3H-leucine incorporation were measured over the growth cycle. For both winter and summer assemblages, low temperature limited growth even when resources (C, N, and P) were added. When temperature was adequate, bacterial growth in dilution cultures was co-limited by C, N, and E Additions of either C, P, or N and P alone provide little or only modest stimulation of growth, suggesting that under in situ conditions both nutrients and organic carbon limit bacterial growth. Our results provide little evidence of seasonal adaptation to low temperatures for bacterial communities in temperate lakes. Instead, bacterial growth appears to be temperature limited during winter and resource limited during summer. We propose that, in general, bacterial growth rates are temperature dependent up to a threshold, but that the patterns of change across temperature gradients are resource dependent, such that temperature has little effect on growth in resource-rich environments but a strong effect in resource-poor environments.
๐ SIMILAR VOLUMES
Mycelia of Neurospora crassa growing with quite different rates at a given temperature (30 ~ C) are obtained by changing the composition of the culture medium: for instance a duplication time of 220 min is found when cultures are growing in Vogel's minimal medium supplemented with glycerol and one o