title: Cyanopeptolin 963A, a chymotrypsin inhibitor of Microcystis PCC 7806.
abstract: A new depsipeptide, cyanopeptolin 963 A (1), was isolated from an axenic strain of the toxic freshwater cyanobacterium Microcystis PCC 7806. The structure of this compound was elucidated by chemical and spectroscopic analyses, including high-resolution ESI-FTICR-MS, 2-D NMR, and GC-MS of the hydrolysate. The major structural difference compared to previously characterized cyanopeptolins of this strain is the replacement of the basic amino acid in position 3 by L-tyrosine. Compound 1 displayed inhibitory activity against chymotrypsin with an IC50 value of 0.9 microM.
authors.affiliation: Limnological Station, Institute of Plant Biology, University of Zürich, Seestrasse 187, 8802 Kilchberg, Switzerland.
authors.forename: Bojan
authors.initials: B
authors.lastname: Bister
authors.forename: Simone
authors.initials: S
authors.lastname: Keller
authors.forename: Heike I
authors.initials: HI
authors.lastname: Baumann
authors.forename: Graeme
authors.initials: G
authors.lastname: Nicholson
authors.forename: Stefan
authors.initials: S
authors.lastname: Weist
authors.forename: Günther
authors.initials: G
authors.lastname: Jung
authors.forename: Roderich D
authors.initials: RD
authors.lastname: Süssmuth
authors.forename: Friedrich
authors.initials: F
authors.lastname: Jüttner
mesh_terms: D002918:Chymotrypsin / Q000037:antagonists & inhibitors*; D047630:Depsipeptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D046931:Microcystis / Q000737:chemistry*; D015394:Molecular Structure; D021241:Spectrometry, Mass, Electrospray Ionization; D013329:Structure-Activity Relationship; D014443:Tyrosine / Q000737:chemistry
chemical_list: D047630:Depsipeptides; D004791:Enzyme Inhibitors; C493713:cyanopeptolin 963A; D014443:Tyrosine; D002918:Chymotrypsin