Acquisition of iron by Trichodesmium and associated bacteria in culture
Article first published online: 27 NOV 2011
© 2011 Society for Applied Microbiology and Blackwell Publishing Ltd
Special Issue: Microbe:Metal Interactions
Volume 14, Issue 7, pages 1681–1695, July 2012
How to Cite
Roe, K. L., Barbeau, K., Mann, E. L. and Haygood, M. G. (2012), Acquisition of iron by Trichodesmium and associated bacteria in culture. Environmental Microbiology, 14: 1681–1695. doi: 10.1111/j.1462-2920.2011.02653.x
- Issue published online: 2 JUL 2012
- Article first published online: 27 NOV 2011
- Received 23 June, 2011; revised 21 October, 2011; accepted 27 October, 2011.
Trichodesmium colonies contain an abundant microbial consortium that is likely to play a role in nutrient cycling within the colony. This study used laboratory cultures of Trichodesmium and two genome-sequenced strains of bacteria typical of Trichodesmium-associated microbes to develop an understanding of the cycling of iron, a potentially limiting micronutrient, within Trichodesmium colonies. We found that the ferric siderophores desferrioxamine B and aerobactin were not readily bioavailable to Trichodesmium, relative to ferric chloride or citrate-associated iron. In contrast, the representative bacterial strains we studied were able to acquire iron from all of the iron sources, implying that naturally occurring Trichodesmium-associated bacteria may be capable of utilizing a more diverse array of iron sources than Trichodesmium. From the organism-specific uptake data collected in this study, a theoretical Trichodesmium colony was designed to model whole colony iron uptake. The bacteria accounted for most (> 70%) of the iron acquired by the colony, highlighting the importance of determining organism-specific uptake in a complex environment. Our findings suggest that, although they may share the same micro-environment, Trichodesmium and its colony-associated microbial cohort may differ substantially in terms of iron acquisition strategy.