Present address: Department of Marine Science, University of Georgia, 247 Marine Science Bldg., Athens, Georgia 30602, USA.
COMPARISON OF CULTURED TRICHODESMIUM (CYANOPHYCEAE) WITH SPECIES CHARACTERIZED FROM THE FIELD1
Version of Record online: 14 DEC 2011
© 2011 Phycological Society of America
Journal of Phycology
Volume 48, Issue 1, pages 196–210, February 2012
How to Cite
Hynes, A. M., Webb, E. A., Doney, S. C. and Waterbury, J. B. (2012), COMPARISON OF CULTURED TRICHODESMIUM (CYANOPHYCEAE) WITH SPECIES CHARACTERIZED FROM THE FIELD. Journal of Phycology, 48: 196–210. doi: 10.1111/j.1529-8817.2011.01096.x
Received 29 January 2010. Accepted 6 May 2011.
- Issue online: 1 FEB 2012
- Version of Record online: 14 DEC 2011
- 16S rRNA gene;
- N2 fixation;
The filamentous, colonial cyanobacterium Trichodesmium has six well-described species, but many more names. Traditional classification was based on field samples using morphological characteristics such as cell width and length, gas vesicle distribution, and colony morphology. We used the Woods Hole Trichodesmium culture collection to identify 21 cultured strains to species using cell morphology; phycobiliprotein absorption spectra; and sequences of the 16S rRNA gene, the 16S–23S internal transcribed spacer (ITS), and the heterocyst differentiation gene hetR. We compared our results to previous studies of field specimens and found similar clades, though not all phylogenetic groups were represented in culture. Our culture collection represented two of the four major clades of Trichodesmium: clade I, made up of Trichodesmium thiebautii Gomont, Trichodesmium tenue Wille, Katagnymene spiralis Lemmerm., and Trichodesmium hildebrandtii Gomont; and clade III, consisting of Trichodesmium erythraeum Ehrenb. and Trichodesmium contortum Wille. These clades were genetically coherent with similar phycobiliprotein composition, but morphologically diverse. In the continual revision of cyanobacterial taxonomy, genetic and biochemical information is useful and informative complements to morphology for the development of a functional classification scheme.