CHM333H5 Lecture Notes - Lecture 7: Ribose, Nitrogenase, Deoxyribose
Document Summary
Crystal structure: zn2+ in centre of distorted tetrahedron, ligands his, his, glu, h2o (69, 196, 72) Catalyzes the hydrolysis of peptide bonds from the c-terminal end of polypeptides. 2 catalytic zn, 1 per subunit: cys, cys, his, h2o (46, 174, 67) 2 structural zn, 1 per subunit: 4 cys (97, 100, 103, 111) 1 zn per subunit: 4 cys (109, 114, 138, 141) Regulatory protein tf iiia binds to dna during gene expression. When zn2+ removed, protein does not bind to dna, therefore structure of the protein is destroyed. Fe (ii) and fe (iii) complexes readily undergo redox and acid-base reactions. Binuclear fe centre enzyme; free radical mechanism deoxyribonucleotide diphosphate + h2o. O2 activating enzymes - peroxidase, catalase, cytochrome p450 (insert l-porphyrin scan) Cleave o2 and incorporate oxygen into organic substrate b. Loosely bound mononuclear fe (ii) centres - monooxygenases. Cleave o2 and incorporate one o into substrate and the other into h2o c. d. e.
