[Preface for special issue on industrial microorganisms: innovation and breakthrough (2021)].

Industrial microorganisms and their products are widely used in various fields such as industry, agriculture, and medicine, which play a pivotal role in economy. Efficient industrial strains are the key to improve production efficiency, and advanced fermentation technology as well as instrument platform is also important to develop microbial metabolic potential. In recent years, rapid development has been achieved in research of industrial microorganisms. Artificial intelligence, efficient genome-editing and synthetic biology technologies have been increasingly applied, and related industrial applications are being accomplished. In order to promote utilization of industrial microorganisms in biological manufacturing, we organized this special issue on innovation and breakthrough of industrial microorganisms. Progress including microbial strain diversity and metabolism, strain development technology, fermentation process optimization and scale-up, high-throughput droplet culture system, and applications of industrial microorganisms is summarized in this special issue, and prospects on future studies are proposed.