Development of a Cost-Efficient PHA Production Platform Utilizing Plant Oils in a Thermotolerant Microorganism

Abstract

In the industrial production of polyhydroxyalkanoates (PHAs), carbon sources and energy consumption contribute significantly to the overall cost, comprising approximately 50% and 20% of total expenses, respectively. Plant oils are attractive feedstocks due to their low cost and high energy density. Thermotolerant bacteria capable of growing at high temperature offer additional advantages, such as enhanced oil solubility. However, a thermotolerant strain used in this study initially lacks efficient lipid metabolism. To overcome this, we introduced lipid metabolism pathways and identified an appropriate inducible promoter system. Although the strain naturally possesses PHA biosynthetic operons, its native PHA accumulation is relatively low compared to conventional PHA producers. Therefore, we will further optimize the expression of PHA biosynthesis genes to improve production. Taken together, this study presents a cost-efficient PHA production platform through inducible system engineering and metabolic enhancement of both oil utilization and PHA biosynthesis