title: Isolation of anteiso-C17, iso-C17, iso-C16, and iso-C15 bacillomycin D from Bacillus amyloliquefaciens SD-32 and their antifungal activities against plant pathogens.
abstract: Two new cyclic lipopeptides (3 and 4) were isolated from the culture filtrate of Bacillus amyloliquefaciens strain SD-32, together with two known metabolites, iso-C15 and iso-C16 bacillomycin D (1 and 2). Spectroscopic and chemical analyses identified the structures of the new compounds 3 and 4 as anteiso-C17 bacillomycin D, cyclic (l-Asn-d-Tyr-d-Asn-l-Pro-l-Glu-d-Ser-l-Thr-3-amino-14-methylhexadecanoic acid) and iso-C17 bacillomycin D, cyclic (l-Asn-d-Tyr-d-Asn-l-Pro-l-Glu-d-Ser-l-Thr-3-amino-15-methylhexadecanoic acid), respectively. The absolute configuration of C-3 in the β-amino fatty acid was determined to be R on the basis of the CD spectrum of its dinitrophenyl-p-methoxyaniline derivative. The activities of compounds 1-4 were evaluated against 13 plant pathogens: the activities of anteiso- and iso-C17 bacillomycin D (3 and 4) were almost the same and stronger than those of iso-C15 and iso-C16 bacillomycin D (1 and 2); iso-C15 bacillomycin D (1) was weakest. Compounds 2-4 inhibited the growth of all fungi tested; however, Pythium aphanidermatum was not inhibited at all by any of the compounds. Furthermore, compounds 1-4 at concentrations of 80, 40, 30, and 30 μM, respectively, inhibited completely the Botrytis cinerea infection in cucumber leaf.
authors.affiliation: Tsukuba Research and Technology Center, SDS Biotech K.K., Midorigahara, Tsukuba, Ibaraki 300-2646, Japan.
authors.forename: Keijitsu
authors.initials: K
authors.lastname: Tanaka
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ishihara
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Nakajima
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides; D001407:Bacillus / Q000737:chemistry* / Q000378:metabolism; D005658:Fungi / Q000187:drug effects*; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology*; D010935:Plant Diseases / Q000382:microbiology
chemical_list: D000935:Antifungal Agents; D023181:Antimicrobial Cationic Peptides; D010455:Peptides; C027845:bacillomycin D