Genetic Engineering Of Bacteria For Enhanced Production Of PHA-Based Bioplastics

Abstract

The growing environmental concerns associated with conventional plastics have led to increased interest in biodegradable alternatives like polyhydroxyalkanoates (PHAs). This study explores genetic engineering strategies to enhance PHA production in bacteria. We systematically modified key biosynthetic pathways in Cupriavidus necator to improve PHA yields and properties. Overexpression of phaCAB operon genes increased PHA content by 37%. Modulating fatty acid metabolism via fadA and fadB deletions enhanced medium-chain-length PHA incorporation. Cofactor availability was improved through zwf overexpression, boosting PHA titers by 28%. A novel CRISPR-Cas9 multiplexing approach allowed simultaneous modification of 5 target genes, resulting in a 2.4-fold increase in volumetric productivity. The engineered strains produced up to 182 g/L of PHA with 89% PHA content. This work demonstrates the potential of rational metabolic engineering to develop superior microbial cell factories for industrial bioplastic production.