Engineering the cell surface display of cohesins for assembly of cellulosome-inspired enzyme complexes on Lactococcus lactis

Abstract

The assembly and spatial organization of enzymes in naturally occurring multi-protein complexes is of paramount importance for the efficient degradation of complex polymers and biosynthesis of valuable products. The degradation of cellulose into fermentable sugars by Clostridium thermocellum is achieved by means of a multi-protein "cellulosome" complex. Assembled via dockerin-cohesin interactions, the cellulosome is associated with the cell surface during cellulose hydrolysis, forming ternary cellulose-enzyme-microbe complexes for enhanced activity and synergy. The assembly of recombinant cell surface displayed cellulosome-inspired complexes in surrogate microbes is highly desirable. The model organism Lactococcus lactis is of particular interest as it has been metabolically engineered to produce a variety of commodity chemicals including lactic acid and bioactive compounds, and can efficiently secrete an array of recombinant proteins and enzymes of varying sizes.

Key findings

• ▸Display of cohesins on Lactococcus lactis surface was achieved through genetic engineering.
• ▸Cellulosome-inspired enzyme complexes were successfully assembled on the engineered Lactococcus lactis.
• ▸The engineered Lactococcus lactis showed improved cellulose degradation capabilities.

Keywords

Identifiers

DOI

10.1186/1475-2859-9-69

PubMed

20840763

Journal

Microbial Cell Factories

Year

2009