Regulation of cephalosporin biosynthesis.

The filamentous fungus Acremonium chrysogenum is the natural producer of the beta-lactam antibiotic cephalosporin C and is as such used worldwide in major biotechnical applications. Albeit its profound industrial importance, there is still a limited understanding about the molecular mechanisms regulating cephalosporin biosynthesis in this fungus. This review focuses on various regulatory levels of cephalosporin biosynthesis. In addition to precursor and antibiotic biosynthesis, molecular genetic characteristics of cephalosporin biosynthesis genes and the knowledge of multiple layers of their regulatory expressional control, as well as the function of activators or repressors on cephalosporin biosynthesis are jointly being surveyed. Furthermore, this review summarizes (i) molecular features, which distinguish strains with different production levels and (ii) examples of molecular engineering approaches to A. chrysogenum.