What makes Pichia pastoris an attractive host for recombinant protein production?

Pichia pastoris (Komagataella phaffii) offers advantages combining prokaryotic and eukaryotic features. Benefits: strong, tightly regulated AOX1 promoter (methanol-inducible, up to 30% of total mRNA), high-density fermentation (>100 g/L dry cell weight), effective protein secretion, eukaryotic post-translational modifications, GRAS status, and genetic stability of integrated constructs. Compared to S. cerevisiae: lower hyperglycosylation, better secretion efficiency, and higher growth density. Applications: industrial enzymes, pharmaceutical proteins, and research tools. Glycoengineered strains produce human-like glycosylation. Limitations: methanol handling requirements (although glucose-based promoters now available), slower growth than E. coli, and secretion bottlenecks for some proteins. Commercial kits and extensive literature support adoption.