Hisashi Matsuda

Microginin, an angiotensin-converting enzyme inhibitor from the blue-green alga Microcystis aeruginosa

Abstract Microginin, an angiotensin-converting enzyme inhibitory pentapeptide, was isolated from the freshwater blue-green alga Microcystis aeruginosa . Its structure was elucidated to be 1 on the basis of 2D NMR data and chemical degradation.

Aeruginosins, protease inhibitors from the cyanobacterium Microcystis aeruginosa

Abstract Five new protease inhibitors, related to aeruginosins 298-A (5), 98-A (1) and 98-B (2), were isolated from the cyanobacterium Microcystis aeruginosa. Aeruginosins 98-C (3) and 101 (4) differed from 1 in the Hpla unit. Aeruginosin 298-B (6) lacked the argininol unit in 5. Aeruginosins 89-A (7) and 89-B (8) were observed as the tautomers in HPLC because of the presence of the argininal units. Structures 3, 4 and 6–8 were determined on the basis of spectral data and chromatographic analyses of degradation products. The absolute stereochemistry of 1–8 was deduced by a combination of spectral and chemical studies. Aeruginosins 98-A to 98-C, 101, 298-A, 298-B, 89-A and 89-B were isolated from the cyanobacterium Microcystis aeruginosa. These compounds except aeruginosin 298-B had trypsin, plasmin and thrombin inhibitory activities. Their structures were determined on the basis of spectral data and amino acid analysis. Their absolute stereochemistries were deduced by a combination of spectral and chemical studies.

Aeruginosin 298-A, a thrombin and trypsin inhibitor from the blue-green alga Microcystis aeruginosa (NIES-298)

Abstract Aeruginosin 298-A was isolated from the freshwater blue-green alga Microcystis aeruginosa (NIES-298). Its structure was elucidated to be 1 on the basis of 2D NMR data. This linear peptide inhibited thrombin and trypsin potently.

Aeruginosins 98-A and B, trypsin inhibitors from the blue-green alga Microcystis aeruginosa (NIES-98)

Aeruginosins 98-A and B, trypsin inhibitors, were isolated from the cultured freshwater blue-green alga Microcystis aeruginosa. Their structures were elucidated to be 1 and 2 respectively on the basis of 2D NMR data and chemical degradation. These peptides inhibited trypsin potently with an IC50 of 0.6 μg/ml.

Micropeptins A and B, plasmin and trypsin inhibitors from the blue-green alga Microcystis aeruginosa

Abstract Micropeptins A and B were isolated from the cultured freshwater blue-green alga Microcystis aeruginosa. Their structures were elucidated to be 1 and 2 on the basis of 2D NMR data and chemical degradation. These cyclic depsipeptides inhibited plasmin and trypsin potently.

Aeruginosins 102-A and B, new thrombin inhibitors from the cyanobacterium Microcystis viridis (NIES-102)

Abstract Aeruginosins 102-A and B were isolated from the freshwater cyanobacterium Microcystis aeruginosa (NIES-102). Their structures were elucidated to be 1 and 2 on the basis of 2D NMR data and chemical degradation. These peptides inhibited thrombin potently.

Microviridins D-F, serine protease inhibitors from the cyanobacterium Oscillatoria agardhii (NIES-204)☆

Abstract New serine protease inhibitors, microviridins D, E and F, were isolated from the cyanobacterium Oscillatoria agardhii (NIES-204). Their structures were elucidated to be 1–3 by extensive 2D NMR data and chemical degradation. These dicyclic or cyclic peptides inhibited serine protease potently.

New microviridins, elastase inhibitors from the blue-green alga Microcystis aeruginosa

Abstract Microviridios B and C were isolated from the freshwater blue-green alga Microcystis aeruginosa (NIES-298). Their structures were elucidated to be 1 and 2 on the basis of 2D NMR data and chemical degradation. These peptides inhibited elastase potently.

Micropeptin 90, a plasmin and trypsin inhibitor from the blue-green alga Microcystis aeruginosa (NIES-90)

Abstract Micropeptin 90, a plasmin and trypsin inhibitor, was isolated from the cultured freshwater blue-green alga Microcystis aeruginosa (NIES-90). Its structure was elucidated to be 1 on the basis of 2D NMR data and chemical degradation. This cyclic depsipeptide inhibited plasmin and trypsin potently with IC50 of 0.1 and 2.0 μg/ml, respectively.

Microviridins, elastase inhibitors from the cyanobacterium Nostoc minutum (NIES-26)

Abstract Two new microviridin-type peptides were isolated from the freshwater cyanobacterium Nostoc minutum (NIES-26), which we named microviridin G and H. Their structures were shown to be 1 and 2 respectively, on the basis of 2D NMR data and chemical degradation. These peptides inhibited elastase potently.