title: Antifungal activity of tautomycin and related compounds against Sclerotinia sclerotiorum.
abstract: The potential of tautomycin to control oilseed rape stem rot was investigated in this paper. Tautomycin produced by Streptomyces spiroverticillatus strongly inhibited Sclerotinia sclerotiorum, which causes oilseed rape stem rot. Tautomycin showed great inhibition of the mycelial growth of S. sclerotiorum on potato dextrose agar (PDA) plates. The values of EC(50) and MIC were 3.26 × 10(-4) mM and 6.52 × 10(-4) mM, respectively. Tautomycin treatment also resulted in morphological abnormalities of S. sclerotiorum such as hyphal swellings and abnormally branched shapes, which were observed microscopically. Sclerotia of S. sclerotiorum soaked in the tautomycin solution for 24 h remained viable, but their ability to undergo myceliogenic germination on PDA plates was completely inhibited when the concentration of tautomycin reached 6.52 × 10(-4) mM. Tautomycin-treated oilseed rape leaves were found to have a low incidence of leaf blight caused by S. sclerotiorum. The activity of the protein phosphatase (PP) in S. sclerotiorum decreased by 41.6% and 52.6% when treated with 3.30 × 10(-4) mM and 6.52 × 10(-4) mM tautomycin, respectively. Cellular constituents also leaked from S. sclerotiorum cells incubated with tautomycin. The results suggest that the antimicrobial activity of tautomycin is due to the inhibition of the PP and then a change of membrane permeability. This paper also investigated related compounds that possess either a maleic anhydride or maleic acid moiety. Results showed 2,3-dimethylmaleic anhydride, diphenylmaleic anhydride and dimethyl maleate demonstrated significant activity against S. sclerotiorum. The values of EC(50) for these three compounds were 0.31 mM, 0.15 mM and 3.99 mM, respectively. The MIC values obtained for these compounds were 1.11 mM, 0.56 mM and 9.58 mM, respectively.
authors.affiliation: Institute of Fermentation Engineering, College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou, PR China. richard_chen@zjut.edu.cn
authors.forename: Xiaolong
authors.initials: X
authors.lastname: Chen
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhu
authors.forename: Yicheng
authors.initials: Y
authors.lastname: Ding
authors.forename: Yinchu
authors.initials: Y
authors.lastname: Shen
mesh_terms: D000935:Antifungal Agents / Q000302:isolation & purification / Q000494:pharmacology*; D001203:Ascomycota / Q000166:cytology / Q000187:drug effects*; D029741:Brassica rapa / Q000382:microbiology; D003470:Culture Media / Q000737:chemistry; D005656:Fungal Proteins / Q000037:antagonists & inhibitors; D025301:Hyphae / Q000166:cytology / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects; D008958:Models, Molecular; D015394:Molecular Structure; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D010935:Plant Diseases / Q000382:microbiology; D018515:Plant Leaves / Q000382:microbiology; D011714:Pyrans / Q000302:isolation & purification / Q000494:pharmacology*; D013141:Spiro Compounds / Q000302:isolation & purification / Q000494:pharmacology*; D013302:Streptomyces / Q000737:chemistry
chemical_list: D000935:Antifungal Agents; D003470:Culture Media; D005656:Fungal Proteins; D011714:Pyrans; D013141:Spiro Compounds; C053079:tautomycin; D010749:Phosphoprotein Phosphatases