INTERACTIONS BETWEEN HEPARINOIDS AND ALCOHOL-DEHYDROGENASE

The interaction between polysulfated polysaccharides (low-molecular-we ight heparin LMWH, dextran sulfate DS and pentosan sulfate PS) and yea st alcohol dehydrogenase (YADH) was investigated. The fluorescence and UV spectra of YADH after adding the tested polysaccharides have confi rmed the interaction between the enzyme and these compounds. Kinetic s tudies have shown that LMWH, DS and PS are inhibitors of YADH (mixed t ype with respect to NAD). The most potent inhibitor is PS (ID50 = 37.5 ng/ml, K-i = 0.6 mu M). The inhibition effect depends on the ionic st rength (the inhibition decreased by about 50% in the presence of 100 m M Na2SO4) and pH value (the inhibition decreased at pH > 7). The resul ts indicate that the inhibition effect of these polyanions is caused b y their electrostatic interactions with the NAD-binding region of YADH .