engleski

Lapstatin, a new aminopeptidase inhibitor produced by Streptomyces rimosus, inhibits autogenous aminopeptidase

Lapstatin, a low-molecular-weight aminopeptidase inhibitor, was purified to homogeneity from Streptomyces rimosus culture filtrates. The purification procedure included extraction with methanol, followed by chromatography on Dowex 50WX, AG 50WX4, and HPLC RP C_18 columns. By amino acid analysis, mass spectrometry, and NMR spectroscopy, the structure of lapstatin was shown to be 3-amino-2-hydroxy-4-methylpentanoylvaline. Lapstatin inhibited the extracellular leucine aminopeptidases from Streptomyces rimosus, Streptomyces griseus, and Aeromonas proteolytica with an IC_50 in the range of 0.3-2.4 ľM. IC_50 values for other enzymes tested were at least tenfold higher. Leucine aminopeptidase from Streptomyces griseus was inhibited in a competitive manner, with an inhibition constant of 5x10^-7 M. Lapstatin is the first low-molecular-weight compound isolated from streptomycetes shown to inhibit an autogenous aminopeptidase.

extracellular peptide inhibitor; leucine aminopeptidase; Streptomyces rimosus

nije evidentirano