Research progress in the synthesis and regulation of pullulan in Aureobasidium spp.

Abstract:

Pullulan is an exopolysaccharide produced by Aureobasidium spp.Despite its widespread biotechnological applications,the mechanisms underlying the biosynthesis and regulation of pullulan remain to be studied.In recent years,researchers have employed molecular biological techniques to elucidate the molecular mechanisms of pullulan synthesis and regulation.The transmembrane protein AmAgs2 is identified as a key enzyme for the synthesis of pullulan,and the cAMP-protein kinase A (cAMP-PKA),target of rapamycin 1(TORC1),high osmotic glycerol 1(HOG1),and sucrose nonfermentable 1(Snf1) signaling pathways are involved in the regulation of pullulan synthesis.We reviewed the research progress in this field,aiming to give insights into the research on the synthesis and regulation mechanisms of fungal extracellular polysaccharide and provide theoretical support for building cell factories with high yields of pullulan.

Key words:Aureobasidium spp.;pullulan;synthetic pathway;regulatory mechanism;signaling pathway