1-01: Systems biology analysis of natural biomass utilization systems for the conversion improvement

Many natural biomass utilization systems (NBUS) can efficiently degrade ligocellulosics. Recently, we have carried out comprehensive systems biology analysis of several highly efficient NBUS including grasshopper gut, cattle rumen, cutworm gut, and termite for both mechanism studies and reverse design of biocatalyst mixtures, engineered microbial strains, and novel conversion processes. These studies revealed several key features of NBUS. First, NBUS can respond to the biomass composition with dynamic changes of their microbial and biocatalyst composition as revealed by the metagenomic and metaproteomic analysis of rumen from cattle fed with different types of biomass. Second, the host and symbiotic biocatalysts complement with one another to achieve the ultimate efficiency for biomass degradation in termites as revealed by the termite genome and transcriptome sequencing. Third, diverse biomass utilization routes can be found from insects with diverse food sources as revealed by comparative metagenome sequencing of grasshopper and cutworm symbionts. Fourth, many enzymes with unique features have been cloned and characterized. Based on these analyses, translational research has been carried out to develop the enzyme mixtures for conversion, engineer the microbial strains for CBP, and complement the white-rot fungi based biological pretreatment. Preliminary studies indicated that the integration of the components from different NBUS can greatly improve the efficiency and rate the fungi-based biological pretreatment. Overall, the systems level understanding and integration of NBUS can improve the feasibility and effectiveness of novel bioconversion concepts like biological pretreatment and CBP enable a biomass conversion process using mostly biological components and at benign conditions.