Medicinal Chemistry

Ashraf SA El-Sayed

Publications

• Research Article
  Biochemical and Pharmacokinetic Properties of Aspergillus flavipes Glutathione-Homocystine Transhydrogenase of Unique Affinity for Homocystine Reduction using GSH as Hydrogen Donor
  
  Author(s): Ashraf SA El-Sayed, Abdallaa E Hassan, Marwa A Yassin, Hend MM Ibrahim and Asmaa M HassanAshraf SA El-Sayed, Abdallaa E Hassan, Marwa A Yassin, Hend MM Ibrahim and Asmaa M Hassan
  
  Glutathione-Homocystine Transhydrogenase (GHTHase) was characterized from Aspergillus flavipes as a novel enzymeof high specificity to reduce homocystine to homocysteine using GSH as hydrogen donor. GHTHase was further conjugated to mono-functional carboxyl polyethylene glycol (PEG) to improve its catalytic properties for various therapeutic uses especially against homocystinuria. The biochemical properties of free and PEG-GHTHase were assessed. The enzyme molecular mass was increased by 1.2 % (from 80 to 95 kDa) by PEG conjugation. The free and PEG-GHTHase have the same pH stability (6.5-8.0) and thermal stability (T1/2 1.0-1.3 h, at 50°C). Kinetically, the affinity and catalytic efficiency of PEG-GHTHase was decreased by 15% to GSH as hydrogen donor for reduction of homocystine than free enzyme. PEG-GHTHase has a slightly stability for suicide i.. Read More»
  DOI: 10.4172/2161-0444.1000265

  Abstract