Microbial Synthesis of Poly-γ-glutamic Acid: Current Progress, Challenges, and Future Perspectives

Overview

Journal Biotechnol Biofuels

Publisher Biomed Central

Specialty Biotechnology

Date 2016 Jul 2

PMID 27366207

Citations 65

Authors

Zhiting Luo

Yuan Guo

Jidong Liu

Hua Qiu

Mouming Zhao

Wei Zou

Shubo Li

Affiliations

Soon will be listed here.

Abstract

Poly-γ-glutamic acid (γ-PGA) is a naturally occurring biopolymer made from repeating units of l-glutamic acid, d-glutamic acid, or both. Since some bacteria are capable of vigorous γ-PGA biosynthesis from renewable biomass, γ-PGA is considered a promising bio-based chemical and is already widely used in the food, medical, and wastewater industries due to its biodegradable, non-toxic, and non-immunogenic properties. In this review, we consider the properties, biosynthetic pathway, production strategies, and applications of γ-PGA. Microbial biosynthesis of γ-PGA and the molecular mechanisms regulating production are covered in particular detail. Genetic engineering and optimization of the growth medium, process control, and downstream processing have proved to be effective strategies for lowering the cost of production, as well as manipulating the molecular mass and conformational/enantiomeric properties that facilitate screening of competitive γ-PGA producers. Finally, future prospects of microbial γ-PGA production are discussed in light of recent progress, challenges, and trends in this field.

Citing Articles

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Analysis of glutamate-dependent mechanism and optimization of fermentation conditions for poly-gamma-glutamic acid production by Bacillus subtilis SCP017-03.

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