Connecting the Carbon Cycle to Iron Metabolism using Functional Genomics and Microbial Physiology
December 10, 2013 11:09: am | by Matthew Hills
Tom Clarke (UEA), Gary Rowley (UEA), Lisa Crossman (TGAC)
Iron oxidising bacteria and iron reducing bacteria control the availability of soluble metal ions in a range of different environments, yet little is known about the microbial physiology of iron oxidising bacteria and whether the two types of bacteria exist independently or symbiotically. The objective of this proposal is to develop protocols for the study of iron oxidising species of bacteria, and establish model organisms that can be used to further these interactions. In doing this we will also co-culture iron oxidising and iron reducing bacteria, both to investigate the effects on microbial physiology and the transcriptome of each species.
Hypothesis to be tested
Co-culturing planktonic iron oxidising bacteria such as Sideroxydans lithotrophicus and iron reducing bacteria such as Shewanella oneidensis should cause enhanced growth of S. lithotrophicus as S. oneidensis recycles Fe2+ and generates carbon dioxide for assimilation by S. lithotrophicus.
The redox cycles of metal ions such as iron and manganese are essential cycles that allow careful balancing of metal concentrations within the environment and allow the support of life in subsurface environments. As shown below these redox cycles also affect the availability of carbon and oxygen and so this project provides a closed system that can be used to measure how different carbon substrates can have an indirect effect on the bioavailability of iron. The ELSA theme of elemental cycles has traditionally focused on the cycles of carbon and nitrogen, this project will expand the theme as well as explore how the other elemental cycles can be connected.