การศึกษาเปรียบเทียบการจับตัวของตะกั่วและทองแดงต่อเซอรูโลพลาสมิน : รายงานผลการวิจัย

• Main Author: สุกัญญา สุนทรส
• Format: Research Report
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 1999
• Subjects: เซอรูโลพลาสมิน; ทองแดง; ตะกั่ว
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:14205
• Institution: Chulalongkorn University

Ceruloplasmin, the copper-transporting protein in human serum carried 8 atoms of copper (Cu) per molecule. The protein also possessed oxidase activity, of which its full function required the presence of coppers. The results from atomic absorption spectrophotometry demonstrated the lead (Pb) could also bind of this proein by replacing the former metal. The binding of both metal reached maximum at pH 6.0, the lead-bound complex was stable for about 3 days while stored at 4 C, the amount decreased with time, only 35% remained on day 18. However, copper could only partially replaced by lead Pb, atomic absorption spectrophotometry showed that only 2 atoms of lead were found on ceruloplasmin molecule. Moreover, lead binding, copper release and decrease of oxidase activity were concentration dependent and corresponded very well with each other. Three metal chelators, namely 2, 3 Dimercapto-1-propane sulfonic acid (DMPS), Ethylenediamine tetrasodium salt (Na[subscript 4]EDTA) and Penicillamine, were used to chelate copper from ceruloplasmin, DMPS was the most effective agent. The decreases in oxidase activity was more pronounced with metal chelators than with lead. In isoelectric focusing gel polyacrylamine electrophoresis of pH4-6, copper or tread could not shift ceruloplasmin band. The dissussion of metal binding sites in ceruloplasmin was included.