Iron nutrition of Trichodesmium

Abstract

The diazotrophic metabolism that allows Trichodesmium to thrive in nitrogen-poor oligotrophic oceans relies on many Fe-containing enzymes and proteins. The iron dependent processes in Trichodesmium and the theoretical amount of iron required for these processess are comparable to the measured iron content of colonies from the open ocean. The high iron requirement of these species is problematic in light of the limited iron delivery to open ocean systems. Trichodesmium can take up soluble forms of iron and has unique mechanisms that may allow it to use iron contained in dust particles. Their ability to add new N through N- fixation and their potential for increasing the amount of biologically available iron make Trichodesmium crucial organisms in the geochemistry of tropical and sub-tropical oceans. -Authors