Novel polyketide synthase from Nectria haematococca.
We identified a polyketide synthase (PKS) gene, pksN, from a strain of Nectria haematococca by complementing a mutant unable to synthesize a red perithecial pigment. pksN encodes a 2,106-amino-acid polypeptide with conserved motifs characteristic of type I PKS enzymatic domains: beta-ketoacyl synthase, acyltransferase, duplicated acyl carrier proteins, and thioesterase. The pksN product groups with the Aspergillus nidulans WA-type PKSs involved in conidial pigmentation and melanin, bikaverin, and aflatoxin biosynthetic pathways. Inactivation of pksN did not cause any visible change in fungal growth, asexual sporulation, or ascospore formation, suggesting that it is involved in a specific developmental function. We propose that pksN encodes a novel PKS required for the perithecial red pigment biosynthesis.
Graziani
Stephane
S
Institut de Génétique et Microbiologie, Université Paris-Sud, 91405 Orsay Cedex, France.
Vasnier
Christelle
C
Daboussi
Marie-Josee
MJ
D001203:Ascomycota / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D015966:Gene Expression Regulation, Fungal; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D010860:Pigments, Biological / Q000096:biosynthesis; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA; D013172:Spores, Fungal / Q000378:metabolism
D009097:Multienzyme Complexes; D010860:Pigments, Biological