Isolation and characterization of guamerin, a new human leukocyte elastase inhibitor from Hirudo nipponia

摘要: A new human leukocyte elastase inhibitor was extracted and purified from a Korean native leech Hirudo nipponia. The inhibitor, called guamerin, has molecular weight of 6,110 shows inhibition constant (Ki) 8.1 x 10(-14) M. It is stable at wide range pH 1 to 11 heat-stable up 90 degrees C. complete amino acid sequence guamerin reveals cysteine-rich polypeptide 57 residues that no similarity any known inhibitors but 51% homology with hirustasin. Guamerin identical spacing 10 cysteine as antistasin-type serine proteinase inhibitors, the P1 reactive site residue Met36 instead Arg. neighboring consists primarily hydrophobic residues. Based on examinations target proteinases specificity, low protein inhibits elastases.