BLG 311 Lecture Notes - Pepsin, Metabolic Pathway, Competitive Inhibition
Document Summary
All enzymes are globular proteins and round in shape. Extracellular enzymes act outside the cell (e. g. digestive enzymes) Enzymes are catalysts speed up chemical reactions. Enzyme is not used up in the reaction (unlike substrates) Affect attraction between substrate and enzyme and therefore efficiency of conversion process. Ionic bonds can break and change shape / enzyme is denatured. Charges on amino acids can change, es complex cannot form. Optimum ph: ph 7 for intracellular enzymes, acidic range (ph 1-6) in the stomach for digestive enzymes (pepsin, alkaline range (ph 8-14) in oral cavities (amylase) Ph measures the conc. of h+ ions - higher conc. will give a lower ph. Enzyme conc. is proportional to rate of reaction, provided other conditions are constant. Substrate conc. is proportional to rate of reaction until there are more substrates than enzymes present. Increases speed of molecular movement chances of molecular collisions more es complexes. At 0-42 c rate of reaction is proportional to temp.