Start Date: Jul 01, 2012
End Date: Jun 30, 2014
We will investigate the cellulolytic strategies of three ruminal bacteria, including the cell-associated complexed cellulase system of Ruminococcus albus 7, the cell-associated non-complexed cellulase system of Fibrobacter succinogenes S85, and the cell-free cellulase system of the actinobacterium Micromonospora ruminantium. Specifically, we will identify the genetic networks that underpin cellulose degradation using transcriptomics, employ functional genomics to predict protein-protein interactions associated with cellulases, and further validate these predictions using cell-free expression. We will use these approaches to characterize monocultures of these bacteria grown on bioenergy feedstocks, in addition to co-cultures of these bacteria with the hemicellulolytic bacteria Prevotella ruminicola 23 or Butyrivibrio proteoclasticus B316. By investigating these different strategies of cellulose degradation, we will gain insights into the fundamental properties that may unify their cellulolytic activity. Moreover, because these bacteria are thought to have co-evolved in the same environment, their interactions with hemicellulolytic bacteria may serve as useful models that could potentially translate into effective approaches for industrial applications.