Polyketides novel

M. G. Bangera and L. S. Thomashow, Identification and characterization of a novel polyketide locus containing 2,4-diacetylphloroglucinol biosynthesis genes from Pseudomonas fluorescens Q2-87. J. Hacteriol. (1997). 

Leighton and coworkers [217] have also used this approach to develop efficient strategies for the synthesis of polyketide-derived natural products [218]. A main motif of these compounds is a skipped polyol structure, as in 6/2-94 this can easily be prepared by a novel Rh-catalyzed domino reaction of a diallylsilyl ether in the presence of CO, followed by a Tamao oxidation [219]. Thus, reaction of, for example, the silane 6/2-93, which is readily prepared from the corresponding ho-... 

Hutchinson, C.R. and Fujii, I. (1995) Polyketide synthase gene manipulation a structure-function approach in engineering novel antibiotics. Annual Review of Microbiology, 49, 201. 

Petkovic, H., Lill, R.E., Sheridan, R.M. et al. (2003) A novel erythromycin, 6-desmethyl erythromycin D, made by substituting an acyltransferase domain of the erythromycin polyketide synthase. The Journal of Antibiotics, 56, 543. 

Ruan, X., Pereda, A., Stassi, D.L. et al. (1997) Acyltransferase domain substitutions in erythromycin polyketide synthase yield novel erythromycin derivatives. Journal of Bacteriology, 179, 6416. 

Kato, Y., Bai, L., Xue, Q. et al. (2002) Functional expression of genes involved in the biosynthesis of the novel polyketide chain extension unit, methoxymalonyl-acyl carrier protein, and engineered biosynthesis of 2-desmethyl-2-methoxy-6-deoxyerythronolide B. Journal of the American Chemical Society, 124, 5268. 

McDaniel, R., Thamchaipenet, A., Gustafsson, C. et al. (1999) Multiple genetic modifications of the erythromycin polyketide synthase to produce a library of novel unnatural natural products. Proceedings of the National Academy of Sciences of the United States of America, 96, 1846. 

Novel polyketides could also be generated by blocking certain catalytic domains of PKSs to allow bypass of the early steps in polyketide biosynthesis. In one example, the Cys729 —> Ala... 

Du, L., Sanchez, C. andShen, B. (2001) Hybrid peptide—polyketide natural products biosynthesis and prospects toward engineering novel molecules. Metabolic Engineering, 3 (1), 78—95. 

Moore, B.S. and Hertweck, C. (2002) Biosynthesis and attachment of novel bacterial polyketide synthase starter units. Natural Product Reports, 19 (1), 70-99. 

UGS1025A, a novel pentacyclic polyketide with an unprecedented furopyrrolizidine skeleton, 46 (Table 4) isolated from the fungus Acremorium sp. KY4917 exhibited antimicrobial and antiproliferative activity against human tumor cell lines. 

In this chapter, we describe the atomic resolution structural elucidation of several plant type III polyketide synthases, including chalcone synthase, 2-pyrone synthase, and stilbene synthase. Manipulation of the catalytic activity and specificity of these biosynthetic enzymes by using a structurally guided approach offers a novel... 

ABE, I., TAKAHASHI, Y., MORITA, H., NOGUCHI, H., Benzalacetone synthase a novel polyketide synthase that plays a crucial role in the biosynthesis of phenylbutanones in Rheum palmatum, Eur. J. Biochem., 2001,268, 3354-3359. 

Yu, J.H. and Leonard, T.J., Sterigmatocystin biosynthesis in Aspergillus nidulans requires a novel type I polyketide S5mthase, J. Bacterial., 177, 4792, 1995. 

SeshimeY etai, Discovery of a novel superfamily of type III polyketide synthases m Aspergillus oryzae, Biochem Biophys Res Commun 331 253-260, 2005. 

These studies have much contributed to deepen our understanding of the biosynthetic mechanisms for polyketide production, particularly with the fundamental discovery of a novel RppA chalcone-synthase-related enzyme in bacteria (Funa 1999). 

Motivated by the value of these natural products, there has been much research focused on developing guidelines for engineering polyketide synthases to generate natural and novel polyketides [445,446], Additionally, manipulation of the biosynthetic pathways of microbial polyketides through engineering permits the biosynthesis of bioactive polyketides not generated naturally [447,448],... 

Chemical study of a marine-derived Penicillium brocae, obtained from a tissue sample of a Fijian Zyzzya sp. sponge, resulted in the isolation and characterization of three novel cytotoxic polyketides, brocaenols A-C 136, 137a, and 137b, possessing an unusual enolized oxepine lactone ring system <2003JOC2014>. 

Teruya T, Suenaga K, Maruyama S, Kurotaki M, Kigoshi H (2005) Biselides A-E Novel Polyketides from an Okinawan Ascidian Didemnidae sp. Tetrahedron 61 6561... 

Ratnayake R, Lacey E, Tennant S, Gill JH, Capon RJ (2007) Kibdelones Novel Anticancer Polyketides from a Rare Australian Actinomycete. Chem Eur J 13 1610... 

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