The Hydrogenase Gene Chip
Metabolic interactions between anaerobic microbes are key for the operation of important natural environments, such as photosynthetic microbial mats and the large human intestine, as well as of engineered systems such as for bioremediation or bioenergy. In particular the transfer of electrons in form of molecular hydrogen is the critical component linking multiple metabolic processes. We have been studying [Fe-Fe] and [Ni-Fe] hydrogenases in molecular details and developed a DNA microarray-based approach to query for the presence and expression status of large numbers of hydrogenases genes in complex microbial communities. Our hydrogenase gene chip contains more than 1000 hydrogenase genes from chemo- and phototrophic microbes, and has been used to predict the flux of molecular hydrogen (i.e. production as well as consumption) in complex communities during bioremediation of chloroethene contaminants by reductive dehalogenation processes, during hydrogen production in cyanobacterial mats, and in metabolic processes associated with Irritable Bowel Syndrome.