Polyphenol oxidase (PPO) (monophenol, o-diphenol: oxygen oxidoreductase; EC 1.14.18.1) is a binuclear copper-cluster-containing monooxygenase ubiquitously present in biological systems (1, 2). PPO may be distinguished from the related oxidase laccase [p-diphenol:oxygen oxidoreductase; EC 1.10.3.2] by its substrate specificity and the type and number of catalytic coppers. PPO catalyzes the oxida...

The uses of shark collagen as a matrix for cell culture and as a substrate for zymography were investigated. Fibroblasts were cultured on a gel matrix of shark type I collagen at 30 degrees C. The collagen gel had contracted by 4 days of incubation. Individual fibroblasts were visible against the transparent background of the contracted collagen as long, lean star-shaped cells. The matrix metal...

Snakebite is a common problem especially in tropical areas all over the world including Iran. Echis carinatus as one of the most dangerous Iranian snakes is spreading in this country excluding central and northwest provinces. In this study gelatinase and fibrinogenolytic properties as two disintegrating matrix metalloproteinase enzymes were evaluated by a strong clear halo between 56-72 kDa in ...

To determine the role of cathepsin L in Echinoderms, starfish (Asterina pectinifera) cathepsin L (ApCtL) was cloned. The results of RT-PCR analysis indicated that the expression of ApCtL in all of the tissues. The pro-mature enzyme of ApCtL, proApCtL, was expressed in Escherichia coli, and cathepsin activity was detected by cleaving of synthetic fluorogenic peptide substrates and gelatin zymogr...

Recently, matrix metalloproteinases (MMP), in particular the gelatinases MMP-2 and MMP-9, generally considered as tumor markers for clinical applications. A longitudinal 2-years follow-up survey was performed on dogs with cutaneous tumor. Serum samples were obtained from 22 dogs with different cutaneous tumors and 22 health dogs at the time of surgery and one month, three months and one year af...

Matrix metalloproteinases (MMPs) disrupt the blood-brain barrier (BBB) during reperfusion. Occludin and claudins are recently described tight junction proteins (TJPs) that form the BBB. We hypothesized that the opening of the BBB was because of the degradation of TJPs by the MMPs. Spontaneously hypertensive rats had a 90 mins middle cerebral artery occlusion with reperfusion for 2, 3, or 24 h. ...