title: The metabolism and biotechnological application of betaine in microorganism.
abstract: Glycine betaine (betaine) is widely distributed in nature and can be found in many microorganisms, including bacteria, archaea, and fungi. Due to its particular functions, many microorganisms utilize betaine as a functional chemical and have evolved different metabolic pathways for the biosynthesis and catabolism of betaine. As in animals and plants, the principle role of betaine is to protect microbial cells against drought, osmotic stress, and temperature stress. In addition, the role of betaine in methyl group metabolism has been observed in a variety of microorganisms. Recent studies have shown that betaine supplementation can improve the performance of microbial strains used for the fermentation of lactate, ethanol, lysine, pyruvate, and vitamin B12, during which betaine can act as stress protectant or methyl donor for the biosynthesis of structurally complex compounds. In this review, we summarize the transport, synthesis, catabolism, and functions of betaine in microorganisms and discuss potential engineering strategies that employ betaine as a methyl donor for the biosynthesis of complex secondary metabolites such as a variety of vitamins, coenzymes, and antibiotics. In conclusion, the biocompatibility, C/N ratio, abundance, and comprehensive metabolic information of betaine collectively indicate that this molecule has great potential for broad applications in microbial biotechnology.
authors.affiliation: College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China. huibinzou@hotmail.com.|CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China. huibinzou@hotmail.com.
authors.forename: Huibin
authors.initials: H
authors.lastname: Zou
authors.affiliation: College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
authors.forename: Ningning
authors.initials: N
authors.lastname: Chen
authors.affiliation: College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
authors.forename: Mengxun
authors.initials: M
authors.lastname: Shi
authors.affiliation: CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Mo
authors.initials: M
authors.lastname: Xian
authors.affiliation: College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Song
authors.affiliation: College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
authors.forename: Junhong
authors.initials: J
authors.lastname: Liu
mesh_terms: D000818:Animals; D001105:Archaea / Q000378:metabolism*; D001419:Bacteria / Q000378:metabolism*; D001622:Betaine / Q000378:metabolism*; D005658:Fungi / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D013312:Stress, Physiological
chemical_list: D001622:Betaine
keywords: Glycine betaine; Metabolic engineering; Metabolic pathways; Methyl group metabolism; One-carbon metabolism; Secondary metabolites