NRPS-like Gene LYS2 Contributed to the Biosynthesis of Cyclo(Pro-Val) in a Multistress-Tolerant Aromatic Probiotic, Meyerozyma guilliermondii GXDK6

Cyclo(Pro-Val) is a diketopiperazine (DKP) found widespread in marine microbes and resulting food products. With new bioactivities of cyclo(Pro-Val) being continually discovered, its potential applications in agriculture and food are becoming more evident, highlighting the need for efficient and practical methods to produce these compounds. However, the biosynthesis mechanisms of cyclo(Pro-Val), particularly in probiotics, remain unclear, and the functional identification of nonribosomal peptide synthases (NRPS) is still limited. This study presents a new efficient cyclo(Pro-Val) production system using the marine probiotic