Three new resorcylic acid derivatives from Sporotrichum laxum.
Sporotrichum laxum ATCC 15155 is the producing strain of the potent anti-Helicobacter pylori natural product spirolaxine (1). Investigation of the secondary metabolites in this fungus led to the isolation of five phthalides (1, 2, 3, 6 and 9) and five resorcylic acid derivatives (4, 5, 7, 8 and 10), among which 5, 7 and 8 are new compounds. The structures were elucidated by spectroscopic analyses, and the absolute configurations of 7 and 8 were determined by Mosher's method. Addition of soy flour into the potato dextrose agar has led to the increased production of 4-10. A biosynthetic pathway consisting of a highly reducing polyketide synthase (PKS), a nonreducing PKS and a series of tailoring enzymes was proposed to produce these fungal natural products. The resorcylic acid derivatives are proposed to result from early hydrolysis of the polyketide chain or incorporation of a longer fatty acyl starter unit.
Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322, United States.
Siyuan
S
Wang
Shuwei
S
Zhang
Tong
T
Zhou
Jixun
J
Zhan
D001572:Benzofurans / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D001688:Biological Products / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D053898:Biosynthetic Pathways; D062385:Hydroxybenzoates / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D048630:Polyketide Synthases / Q000378:metabolism; D012118:Resorcinols / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D013175:Sporothrix / Q000737:chemistry* / Q000201:enzymology / Q000378:metabolism
D001572:Benzofurans; D001688:Biological Products; D062385:Hydroxybenzoates; D012118:Resorcinols; C076950:alpha-resorcylic acid; D048630:Polyketide Synthases; C082022:phthalide
Biosynthetic pathway; Phthalide; Polyketide; Resorcylate; Sporotrichum laxum