Advances in metabolic engineering for the microbial production of short branched-chain fatty acids and short branched-chain alcohols

Abstract:

Short branched-chain fatty acids and short branched-chain alcohols (SBCFAs and SBCAs, C4?6) serve as versatile platform chemicals for the chemical industry. They are commonly used as starting materials or building blocks to produce a wide range of valuable end products in chemical, food and pharmaceutical industries. Therefore, there is a huge demand for such platform chemicals in the global market. Currently, SBCFAs and SBCAs are predominantly produced through traditional chemical synthesis. However, these chemical conversion processes are heavily dependent on fossil fuels and always lead to serious environmental pollution. Moreover, the efficiency of these processes is often low. Recently, rapid developments in metabolic engineering of microbes provide a promising alternative to produce these platform chemicals. These bio-based manufacturing systems using microbial cell factories will help move the industrial production of SBCFAs and SBCAs towards more sustainable, environmentally friendly and economically competitive. Here, we reviewed the current status of metabolic engineering of microbes that produce SBCFAs and SBCAs including microbial hosts, key enzymes, metabolic pathways and engineering of SBCFA/SBCA biosynthesis. Furthermore, key challenges and future perspectives were discussed.