Regulation and compartmentalization of β-lactam biosynthesis.
Bottom Line: Similarly, the Acremonium two-component CefD1-CefD2 epimerization system is also located in microbodies.This compartmentalization implies intracellular transport of isopenicillin N (in the penicillin pathway) or isopenicillin N and penicillin N in the cephalosporin route.Two transporters of the MFS family cefT and cefM are involved in transport of intermediates and/or secretion of cephalosporins.
Affiliation: Institute of Biotechnology of León, Science Park, Avda. Real 1, 24006 León, Spain. firstname.lastname@example.orgShow MeSH
Related in: MedlinePlus
Mentions: β‐Lactams, like many other secondary metabolites, have unusual chemical structures. All β‐lactams contain a four‐membered β‐lactam ring closed by an amide bond (Fig. 1). Penicillins contain a bicyclic ‘penam’ nucleus formed by fused β‐lactam and thiazolidine rings and an acyl side‐chain bound to the amino group at C‐6. They are produced by a few Penicillium and Aspergillus species (Aharonowitz et al., 1992). Recently penicillins have been found to be produced by a few other deuteromycetes (Laich et al., 1999; 2002; 2003). A second β‐lactam compound, cephalosporin C, produced by the fungi Acremonium chrysogenum, Paecilomyces persicinus and Kallichroma tethys (Kim et al., 2003) and some other deuteromycetes, contains the cephem nucleus (a six‐membered dihydrothiazine ring fused to the β‐lactam ring) (Fig. 1). Cephalosporin C has a d‐α‐aminoadipyl side‐chain attached to the C‐7 amino group, which is identical to that of hydrophilic penicillin N but differs from those of hydrophobic penicillins. Penicillins and cephalosporins are of great clinical interest as inhibitors of peptidoglycan biosynthesis in bacteria.
Affiliation: Institute of Biotechnology of León, Science Park, Avda. Real 1, 24006 León, Spain. email@example.com