Genome mining the black-yeast Aureobasidium pullulans NRRL 62031 for biotechnological traits.

Abstract

Aureobasidium pullulans is a yeast-like fungus known for its commercial biomanufacturing of pullulan. This study explores the genome of A. pullulans NRRL 62031, highlighting its biosynthetic potential, metabolic pathways, and physiological traits. Additionally, it demonstrates actual product formation and links molecular features to biotechnological applications. Phylogenetic analysis suggested it might be closely related to Aureobasidium melanogenum. While the functional annotation revealed a wide carbohydrate catabolism, growth evaluation demonstrated that the microbe can utilize not only saccharides but also polyols and organic acids. The extracellular cellulolytic, xylanolytic, and pectinolytic activities were indicated by the formation of visible halos on agar plates. The antiSMASH pipeline, NCBI Blastp alignment, and product qualification confirmed that A. pullulans NRRL 62031 can produce melanin, pullulan, polymalate, and polyol lipids. Moreover, yanuthone D, burnettramic acid A, choline, fructooligosaccharides, gluconic acid, and β-glucan might be synthesized by A. pullulans NRRL 62031. The results clearly show the extraordinary potential of A. pullulans NRRL 62031 as a microbial chassis for valorizing biomass residues into value-added bioproducts. The strong catabolic and anabolic capacities indicate significant promise for biotechnological applications. The results are discussed in the context of metabolic engineering of Aureobasidium.