Three novel protease inhibitors from a natural bloom of the cyanobacterium Microcystis aeruginosa.
Two new trypsin inhibitors, micropeptins EI992 (1) and EI964 (2), and a modified linear peptide aeruginosin EI461 (3) were isolated from the hydrophilic extract of two samples of Microcystis aeruginosa, collected from the Einan Reservoir in Israel. Homonuclear and heteronuclear 2D-NMR techniques as well as HRFABMS determined the gross structures of 1-3. The relative and absolute stereochemistry of 1-3 was deduced by a combination of spectral data and Marfey's method for HPLC. Aeruginosin EI461 (3) differs from the 14 known aeruginosins in the relative and absolute stereochemistry of the Choi-6-hydroxyl substituent.
School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel.
Alexei
A
Ploutno
Maria
M
Shoshan
Shmuel
S
Carmeli
D002851:Chromatography, High Pressure Liquid; D007557:Israel; D013058:Mass Spectrometry; D046931:Microcystis / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D009842:Oligopeptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D011480:Protease Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared
D009842:Oligopeptides; D010456:Peptides, Cyclic; D011480:Protease Inhibitors; C465430:aeruginosin EI461; C465431:micropeptin EI964; C465432:micropeptin EI992