Flavour chemistry and metabolic engineering of microbial synthetic pyrazines: decoding the path to green manufacturing of food aroma components
Wenhua Tong, Yan Wang, Yang Ying, Yongfang Zou, Huibo Luo, Jizhou Pu
Abstract
, as well as some fungi, can synthesize pyrazines. Their biosynthetic pathways remain poorly elucidated, and synthesis efficiency is notoriously low. This review provides a comprehensive synthesis of the current knowledge on microbial pyrazines biosynthesis. We critically analyze the putative pathways and detail the functional roles of key enzymes, such as L-threonine dehydratases and aminotransferases. Furthermore, we evaluate scenario-based strategies for utilizing cheap carbon sources, to enhance the economic feasibility of bioproduction. The significant barriers of low product yield and inherent microbial toxicity are also systematically examined. Finally, we discuss the potential of emerging candidate strains and cell-free metabolic engineering systems for pyrazines synthesis, aiming to establish a foundational roadmap for future research and development in this field.