Microbial Production of Pyruvic, Lactic, and 3-Hydroxy Propionic Acid from Renewable Resources

Microbial production of value-added chemicals is important for establishing a sustainable society. Owing to increasing environmental concerns related to global warming caused by the massive utilization of fossil resources, research efforts to reduce CO2 emissions have increased worldwide. One of the key strategies to reduce CO2 emissions is to change the production processes for material synthesis from chemical to biological processes. Therefore, the utilization of microorganisms is important to achieve this sustainable development goal. Many microorganisms that produce value-added chemicals have been isolated from nature. However, naturally isolated microorganisms rarely produce the target chemicals with high productivity, high yield, and final concentrations. To satisfy these parameters, metabolic engineering approaches are applied to tailor strains for the production of the target chemicals satisfying these three parameters. Besides strain performance, target chemical production from cost-effective resources is essential for practical application to compete with the production costs of chemical processes. In this chapter, we summarize the recent progress in the microbial production of three industrially important organic acids, pyruvic, lactic, and 3-hydroxy propionic acids, which have various applications in many industrial fields.