Stable, efficient, and cost-effective system for the biosynthesis of recombinant bacterial cellulose in Escherichia coli DH5α platform

Abstract

Background Owing to its remarkable mechanical properties that surpass the plant-based cellulose, bacterial cellulose production has been targeted for commercialization during the last few years. However, the large-scale production of cellulose is generally limited by the slow growth of producing strains and low productivity which ultimately makes the commercial production of cellulose using the conventional strains non cost-effective. In this study, we developed a novel plasmid-based expression system for the biosynthesis of cellulose in E.coli DH5α and assessed the cellulose productivity relative to the typically used E.coli BL21 (DE) expression strain. Results No production was detected in BL21 (DE3) cultures upon expression induction; however, cellulose was detected in E.coli DH5α as early as 1 h post-induction. The total yield in induced DH5α cultures was estimated as 200 ± 5.42 mg/L (dry weight) after 18 h induction, which surpassed the yield reported in previous studies and even the wild-type Gluconacetobacterxylinum BRC5 under the same conditions. As confirmed with electron microscope micrograph, E.coli DH5α produced dense cellulose fibers with ~ 10 μm diameter and 1000–3000 μm length, which were remarkably larger and more crystalline than that typically produced by G.hansenii. Conclusions This is the first report on the successful cellulose production in E.coli DH5α which is typically used for plasmid multiplication rather than protein expression, without the need to co-express cmcax and ccpAx regulator genes present in the wild-type genome upstream the bcs-operon, and reportedly essential for the biosynthesis.

Exopolysaccharides Producing Bacteria: A Review

“…Japanese scientists obtained the recombinant E. coli bacteria capable of forming BC resulting from the transfer of G. xylinus genes [ 151 ]. A new stable efficient plasmid-based expression system of recombinant BC in the E. coli DH5_ platform has currently been developed [ 152 ].…”

Bacterial Cellulose-Based Polymer Nanocomposites: A Review

“…Japanese scientists obtained the recombinant E. coli bacteria capable of forming BC resulting from the transfer of G. xylinus genes [ 68 ]. A new stable efficient plasmid-based expression system of recombinant BC in E. coli DH5α platform has currently been developed [ 69 ].…”

Bacterial crystalline cellulose secretion via a supramolecular BcsHD scaffold

“…A better understanding of the cellulose crystallinity determinants can lead to the engineering of bacterial strains or tailored chemi-enzymatic systems for the production of optimized BC and also potentially yield tailored molecular scaffolds for increased efficiency and metabolic flux in other bacterial biosynthetic pathways. Approaches for the expression of Gluconacetobacter Bcs subunits, including BcsD and BcsH, in alternative species such as E. coli have already had some but limited success in inducing crystalline cellulose secretion recombinantly (40)(41)(42), and dissecting the underlying molecular mechanisms has the potential to greatly facilitate such bioengineering efforts. Similarly, c-di-GMP-dependent synthase activation through the enzymes' PilZ domains should be examined in the bigger picture of synthase-cortical belt interactions.…”