Starter unit specificity directs genome mining of polyketide synthase pathways in fungi

被引:43
作者
Crawford, Jason M. [1 ]
Vagstad, Anna L. [1 ]
Ehrlich, Kenneth C. [2 ]
Townsend, Craig A. [1 ]
机构
[1] Johns Hopkins Univ, Dept Chem, Baltimore, MD 21218 USA
[2] USDA, So Reg Res Ctr, New Orleans, LA 70124 USA
关键词
fatty acids; polyketides; fungal metabolites; starter unit : acyl-carrier protein transacylase; aflatoxin;
D O I
10.1016/j.bioorg.2007.11.002
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Search of the protein database with the aflatoxin pathway polyketide synthase (PKS) revealed putative PKSs in the pathogenic fungi Coccidioides immitis and Coccidioides posadasii that could require partnerships with a pair of fatty acid synthase (FAS) subunits for the biosynthesis of fatty acid-polyketide hybrid metabolites. A starter unit: acyl-carrier protein transacylase (SAT) domain was discovered in the nonreducing PKS. This domain is thought to accept the fatty acid product from the FAS to initiate polyketide synthesis. We expressed the C immitis SAT domain in Escherichia coli and showed that this domain, unlike that from the aflatoxin pathway PKS, transferred octanoyl-CoA four times faster than hexanoyl-CoA. The SAT domain also formed a covalent octanoyl intermediate and transferred this group to a free-standing ACP domain. Our results suggest that C immitis/posadasii, both human fungal pathogens, contain a FAS/PKS cluster with functional similarity to the aflatoxin cluster found in Aspergillus species. Dissection of the PKS and determination of in vitro SAT domain specificity provides a tool to uncover the growing number of similar sequenced pathways in fungi, and to guide elucidation of the fatty acid-polyketide hybrid metabolites that they produce. (C) 2007 Elsevier Inc. All rights reserved.
引用
收藏
页码:16 / 22
页数:7
相关论文
共 26 条
[1]   A polyketide synthase gene required for biosynthesis of the aflatoxin-like toxin, dothistromin [J].
Bradshaw, RE ;
Jin, HP ;
Morgan, BS ;
Schwelm, A ;
Teddy, OR ;
Young, CA ;
Zhang, SG .
MYCOPATHOLOGIA, 2006, 161 (05) :283-294
[2]   THE POTENTIAL ROLE OF FATTY-ACID INITIATION IN THE BIOSYNTHESIS OF THE FUNGAL AROMATIC POLYKETIDE AFLATOXIN B-1 [J].
BROBST, SW ;
TOWNSEND, CA .
CANADIAN JOURNAL OF CHEMISTRY, 1994, 72 (01) :200-207
[3]   Aspergillus has distinct fatty acid synthases for primary and secondary metabolism [J].
Brown, DW ;
Adams, TH ;
Keller, NP .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1996, 93 (25) :14873-14877
[4]   INCREASED EXPRESSION OF ASPERGILLUS-PARASITICUS AFLR, ENCODING A SEQUENCE-SPECIFIC DNA-BINDING PROTEIN, RELIEVES NITRATE INHIBITION OF AFLATOXIN BIOSYNTHESIS [J].
CHANG, PK ;
EHRLICH, KC ;
YU, JJ ;
BHATNAGAR, D ;
CLEVELAND, TE .
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 1995, 61 (06) :2372-2377
[5]   Polyketides, proteins and genes in fungi: programmed nano-machines begin to reveal their secrets [J].
Cox, Russell J. .
ORGANIC & BIOMOLECULAR CHEMISTRY, 2007, 5 (13) :2010-2026
[6]   Identification of a starter unit acyl-carrier protein transacylase domain in an iterative type I polyketide synthase [J].
Crawford, Jason M. ;
Dancy, Blair C. R. ;
Hill, Eric A. ;
Udwary, Daniel W. ;
Townsend, Craig A. .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2006, 103 (45) :16728-16733
[7]  
CRAWFORD JM, 2008, CHEM BIO CH IN PRESS
[8]   Aflatoxin biosynthesis gene clusters and flanking regions [J].
Ehrlich, KC ;
Yu, J ;
Cotty, PJ .
JOURNAL OF APPLIED MICROBIOLOGY, 2005, 99 (03) :518-527
[9]   Heterologous expression and product identification of Colletotrichum lagenarium polyketide synthase encoded by the PKS1 gene involved in melanin biosynthesis [J].
Fujii, I ;
Mori, Y ;
Watanabe, A ;
Kubo, Y ;
Tsuji, G ;
Ebizuka, Y .
BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 1999, 63 (08) :1445-1452
[10]   Characterization of two polyketide synthase genes involved in zearalenone biosynthesis in Gibberella zeae [J].
Gaffoor, I ;
Trail, F .
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 2006, 72 (03) :1793-1799