Sortase A-Mediated Ligation Facilitates Metabolic Channeling in Saccharomyces cerevisiae

Although the yeast Saccharomyces cerevisiae has been utilized for the bioproduction of various valuable substances, improving product concentration and production rate remains a challenge in its practical application. In this respect, metabolic channeling represents a potential strategy for addressing this issue. In the metabolic pathway for synthesizing a target product, closing enzymes induce substrate channeling, in which intermediates are transferred to the following enzyme to facilitate processing. To close enzymes in proximity, protein ligation is one of the solutions. However, genetic fusion often causes the generation of inactive complexes, and few techniques exist for ligating enzymes in yeast without loss of enzyme activity. Herein, we focused on sortase A, which links a short peptide tag between two target proteins. First, we demonstrated sortase A-mediated ligation in yeast using split-green fluorescent protein. Then, sortase A-mediated ligation was applied to ligate metabolic enzymes related to 3-hydroxypropionic acid, which improved 3-HP production by 2.42-fold. This strategy represents a novel approach for improving yeast bioproduction.