(1) Identify novel genes for biomass utilization in rhizobium/rhizosphere of wild legumes.
Metatranscriptomic profiling of wild legume rhizosphere microbial communities under
various environmental conditions will be used to identify novel genes and pathways that
could improve xylose use (e.g., novel sugar transporters, xylose metabolizing enzymes,
and xylitol excretion) and lignocellulolytic degradation.
(2) Functional improvement of biomass utilization in
S. cerevisiae. We will test candidate
genes involved in xylose utilization in rhizobium and lignocellulose breakdown in
rhizospher of wild legumes by heterologous expression in S.cerevisiae. We also propose
to utilize high throughput functional "barcoding" assays to identify yeast genes that
modulate sensitivity to commercial lignocellulose fermentation conditions including high
solids concentration, inhibitory compounds present in the hydrolysate of lignocellulosic
biomass, high sugar (xylose, hexoses) and fermentation product (Ethanol and Xylitol
(byproduct) concentrations. Together these two approaches should enable identification
of exogenous and endogenous genes involved in optimal biomass utilization.