Structure and biosynthesis of staphyloxanthin from Staphylococcus aureus.
Most Staphylococcus aureus strains produce the orange carotenoid staphyloxanthin. The staphyloxanthin biosynthesis genes are organized in an operon, crtOPQMN, with a sigma(B)-dependent promoter upstream of crtO and a termination region downstream of crtN. The functions of the five encoded enzymes were predicted on the basis of their sequence similarity to known enzymes and by product analysis of gene deletion mutants. The first step in staphyloxanthin biosynthesis is the head-to-head condensation of two molecules of farnesyl diphosphate to form dehydrosqualene (4,4'-diapophytoene), catalyzed by the dehydrosqualene synthase CrtM. The dehydrosqualene desaturase CrtN dehydrogenates dehydrosqualene to form the yellow, main intermediate 4,4'-diaponeurosporene. CrtP, very likely a mixed function oxidase, oxidizes the terminal methyl group of 4,4'-diaponeurosporene to form 4,4'-diaponeurosporenic acid. CrtQ, a glycosyltransferase, esterifies glucose at the C(1)'' position with the carboxyl group of 4,4'-diaponeurosporenic acid to yield glycosyl 4,4'-diaponeurosporenoate; this compound was the major product in the clone expressing crtPQMN. In the final step, the acyltransferase CrtO esterifies glucose at the C(6)'' position with the carboxyl group of 12-methyltetradecanoic acid to yield staphyloxanthin. Staphyloxanthin overexpressed in Staphylococcus carnosus (pTX-crtOPQMN) and purified was analyzed by high pressure liquid chromatography-mass spectroscopy and NMR spectroscopy. Staphyloxanthin was identified as beta-D-glucopyranosyl 1-O-(4,4'-diaponeurosporen-4-oate)-6-O-(12-methyltetradecanoate).
Pelz
Alexandra
A
Department of Microbial Genetics, University of Tuebingen, Germany.
Wieland
Karsten-Peter
KP
Putzbach
Karsten
K
Hentschel
Petra
P
Albert
Klaus
K
Götz
Friedrich
F
D000217:Acyltransferases / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D049109:Cell Proliferation; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004247:DNA / Q000378:metabolism; D017931:DNA Primers / Q000737:chemistry; D013186:Farnesyl-Diphosphate Farnesyltransferase / Q000235:genetics; D008401:Gas Chromatography-Mass Spectrometry; D016695:Glycosyltransferases / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy; D006899:Mixed Function Oxygenases / Q000235:genetics; D008956:Models, Chemical; D008969:Molecular Sequence Data; D009154:Mutation; D009876:Operon; D010088:Oxidoreductases / Q000235:genetics; D011401:Promoter Regions, Genetic; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D013053:Spectrophotometry; D013211:Staphylococcus aureus / Q000378:metabolism*; D013997:Time Factors; D024341:Xanthophylls / Q000096:biosynthesis* / Q000737:chemistry*
D001426:Bacterial Proteins; D017931:DNA Primers; D024341:Xanthophylls; C031841:staphyloxanthin; D004247:DNA; C091055:CrtN protein, Staphylococcus aureus; D006899:Mixed Function Oxygenases; D010088:Oxidoreductases; C091056:CrtM protein, Staphylococcus aureus; D000217:Acyltransferases; D016695:Glycosyltransferases; D013186:Farnesyl-Diphosphate Farnesyltransferase