Page 131 - Biochemistry2 (08PB403)
P. 131

3. CYP 450 or Cyt P-450: major pathway for hydroxylation of
       xenobiotics. Supply of NADPH is critical for liver microsomal cyt
       P-450.

4. Phagocytosis of microorganisms esp bacteria, foreign particles
       etc by Neutrophils & Macrophages: imp defense mechanism.

a. Oxygen dependent system- MPO [myeloperoxidase system]-
       most potent

NADPH OXIDASE [needs NADPH] in WBC cell memb, converts O2
       into Superoxide FR [Respiratory burst]→Superoxide is
       converted by SOD [superoxide dismutase] into H2O2 →lysosomal
       MPO converts it to hypochlorous acid HOCl·→ kills bacteria

       NADPH OXIDASE deficiency- Chronic granulomatosis
b. Oxygen independent system- pH changes in phagolysosomes and

       lysosomal enzymes- destroy pathogens

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