title: Cryptic Aspergillus nidulans antimicrobials.
abstract: Secondary metabolite (SM) production by fungi is hypothesized to provide some fitness attribute for the producing organisms. However, most SM clusters are "silent" when fungi are grown in traditional laboratory settings, and it is difficult to ascertain any function or activity of these SM cluster products. Recently, the creation of a chromatin remodeling mutant in Aspergillus nidulans induced activation of several cryptic SM gene clusters. Systematic testing of nine purified metabolites from this mutant identified an emodin derivate with efficacy against both human fungal pathogens (inhibiting both spore germination and hyphal growth) and several bacteria. The ability of catalase to diminish this antimicrobial activity implicates reactive oxygen species generation, specifically, the generation of hydrogen peroxide, as the mechanism of emodin hydroxyl activity.
authors.affiliation: Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Steve S
authors.initials: SS
authors.lastname: Giles
authors.forename: Alexandra A
authors.initials: AA
authors.lastname: Soukup
authors.forename: Carrie
authors.initials: C
authors.lastname: Lauer
authors.forename: Mona
authors.initials: M
authors.lastname: Shaaban
authors.forename: Alexander
authors.initials: A
authors.lastname: Lin
authors.forename: Berl R
authors.initials: BR
authors.lastname: Oakley
authors.forename: Clay C C
authors.initials: CC
authors.lastname: Wang
authors.forename: Nancy P
authors.initials: NP
authors.lastname: Keller
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D001233:Aspergillus nidulans / Q000235:genetics* / Q000378:metabolism*; D001688:Biological Products / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology*; D053898:Biosynthetic Pathways / Q000235:genetics; D004642:Emodin / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D006801:Humans; D005810:Multigene Family; D016877:Oxidants / Q000096:biosynthesis / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000890:Anti-Infective Agents; D001688:Biological Products; D016877:Oxidants; D004642:Emodin