In vitro inhibitory effects of some heavy metals on human erythrocyte carbonic anhydrases

EKINCI D., BEYDEMIR S., Kufrevioglu O. I.

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY, cilt.22, sa.6, ss.745-750, 2007 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 22 Sayı: 6
  • Basım Tarihi: 2007
  • Doi Numarası: 10.1080/14756360601176048
  • Dergi Adı: JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.745-750
  • Anahtar Kelimeler: Carbonic anhydrase, heavy metals, inhibition, HCA-I, HCA-II, ENZYME-ACTIVITIES, PURIFICATION, VIVO, RAT, SULFONAMIDES, ISOZYMES, SCAFFOLD, COMPLEX, DRUGS, CRABS
  • Atatürk Üniversitesi Adresli: Evet

Özet

The inhibition of two human carbonic anhydrase (HCA, EC 4.2.1.1) isozymes, the cytosolic HCA I and II, with heavy metal salts of Pb( II), Co(II) and Hg( II) has been investigated. Human erythrocyte CA- I isozyme was purified with a specific activity of 920 EUmg 21 and a yield of 30% and CA- II isozyme was purified with a specific activity of 8000EUmg 21 and a yield of 40% using Sepharose-4B-L tyrosine-sulfanilamide affinity gel chromatography. The overall purification was approximately 104-fold for HCA-I and 900-fold for HCA-II. The inhibitory effects of different heavy metals ( lead, cobalt and mercury) on CA activity were determined at low concentrations using the esterase method under in vitro conditions. Ki values for these metals were calculated from Lineweaver-Burk graphs as 1.0, 3.22 and 1.45mMfor HCA-I and 0.059, 1.382 and 0.32mMfor HCA-II respectively. Lead was a noncompetitive inhibitor for HCA-I and competitive for HCA-II, cobalt was competitive for HCA-I and noncompetitive for HCA-II and mercury was uncompetitive for both HCA-I and HCA-II. Lead was the best inhibitor for both HCA-I and HCA-II.