title: Balticidins A-D, antifungal hassallidin-like lipopeptides from the Baltic Sea cyanobacterium Anabaena cylindrica Bio33.
abstract: Balticidins A-D (1-4), four new antifungal lipopeptides, were isolated from the laboratory-cultivated cyanobacterium Anabaena cylindrica strain Bio33 isolated from a water sample collected from the Baltic Sea, Rügen Island, Germany. Fractionation of the 50% aqueous MeOH extract was performed by bioassay-guided silica gel column chromatography followed by SPE and repeated reversed-phase HPLC. The main fraction containing the compounds exhibited a strong and specific antifungal activity with inhibition zones in an agar-diffusion assay from 21 to 32 mm against Candida albicans, Candida krusei, Candida maltosa, Aspergillus fumigatus, Microsporum gypseum, Mucor sp., and Microsporum canis. The structures were elucidated by multidimensional (1)H and (13)C NMR spectroscopy, HRESIMS, amino acid analysis, and sugar analysis. Spectroscopic data analysis afforded an unambiguous sequence of R.CHO(S1).CHOH.CONH-Thr(1)-Thr(2)-Thr(3)-HOTyr(4)-Dhb(5)-D-Gln(6)-Gly(7)-NMeThr(8)(S2)-L-Gln COOH(9), in which Dhb is dehydroaminobutyric acid, S1 is d(-)-arabinose-(3-1)-D-(+)-galacturonic acid, S2 is D-(+)-mannose, and R is the aliphatic residue -C13H26Cl or -C13H27. Besides NMeThr, D-allo-Thr, D-Thr, and L-Thr were identified, but the position of the enantiomers in the sequence is not clear. The four balticidins differ in their cyclic (2, 4)/linear (1, 3) core and the presence (1, 2)/absence (3, 4) of chlorine in the aliphatic unit.
authors.affiliation: Institute of Pharmacy, Department of Pharmaceutical Biology, Ernst-Moritz-Arndt-University , Friedrich-Ludwig-Jahn-Straße 17, D-17489 Greifswald, Germany.
authors.forename: Thanh-Huong
authors.initials: TH
authors.lastname: Bui
authors.forename: Victor
authors.initials: V
authors.lastname: Wray
authors.forename: Manfred
authors.initials: M
authors.lastname: Nimtz
authors.forename: Torgils
authors.initials: T
authors.lastname: Fossen
authors.forename: Michael
authors.initials: M
authors.lastname: Preisitsch
authors.forename: Gudrun
authors.initials: G
authors.lastname: Schröder
authors.forename: Kristian
authors.initials: K
authors.lastname: Wende
authors.forename: Stefan E
authors.initials: SE
authors.lastname: Heiden
authors.forename: Sabine
authors.initials: S
authors.lastname: Mundt
mesh_terms: D046868:Anabaena cylindrica / Q000737:chemistry*; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001232:Aspergillus fumigatus / Q000187:drug effects; D002176:Candida albicans / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D000458:Cyanobacteria / Q000737:chemistry; D005858:Germany; D055666:Lipopeptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D008864:Microsporum / Q000187:drug effects; D015394:Molecular Structure; D009089:Mucor / Q000187:drug effects; D019906:Nuclear Magnetic Resonance, Biomolecular; D009792:Oceans and Seas; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D000935:Antifungal Agents; D055666:Lipopeptides; D010456:Peptides, Cyclic; C000590848:balticidin A