Heterologous production of cyanophycin withTatumella morbiroseicyanophycin synthetase

Abstract

AbstractMicrobial production of biopolymers represents a promising, sustainable alternative to current approaches for plastic production. Cyanophycin synthetase 1 (CphA1) produces cyanophycin - an attractive biopolymer consisting of a poly-L-aspartic acid backbone decorated with L-arginine side groups. In this work, a series of CphA1 enzymes from different bacteria were screened for heterologous cyanophycin production in engineeredEscherichia coli, from which it was found that CphA1 fromTatumella morbirosei(TmCphA1) was especially productive.TmCphA1 was capable of supporting up to ~2-fold greater yields of insoluble cyanophycin than any other tested CphA1 enzymes, including 10.8-times more than CphA1 fromSynechocystissp. PCC6308. Finally, using a bench-scale bioreactor, cyanophycin production byTmCphA1-expressingE. colireached up to 1.9 g per liter of culture by 48 h.