A piece of the pie: engineering microbiomes by exploiting division of labor in complex polysaccharide consumption

Although microbes competing for simple substrates are wellknown to obey the ecological competitive exclusion principle, little is known regarding how complex substrates influence the ecology of microbial communities. The vast structural diversity of polysaccharides makes them ideal substrates for cooperative microbial degradation. Potential mechanisms for division of metabolic labor in microbial communities consuming polysaccharides are 1) complementary differences in gene content, 2) alternate regulation of polysaccharide degradation genes, 3) subtle differences in hydrolytic enzyme functionality, and 4) specialization in transport and consumption of hydrolysis products. Engineering division of labor in polysaccharide degradation using these mechanisms as control points may improve our ability to engineer microbiomes for improved productivity and stability in diverse environments.