MBB 222 Lecture Notes - Lecture 13: Insulin Receptor, Pilin, Activation Energy

• School: Simon Fraser University
• Department: Molec Biol & Biochem
• Course: MBB 222
• Professor: Irina Kovalyova

Document Summary

Proteins do most of the work in the cell. All proteins work by interacting with other molecules. Proteins are essential for life and necessary for all all cell processes, including dna replication, Almost every biochemical reaction is catalyzed by an enzyme. Enzymes have extraordinary catalytic power: highly specific tremendous acceleration of chemical reactions, a(cid:272)t i(cid:374) a(cid:395)ueous e(cid:374)(cid:448)i(cid:396)o(cid:374)(cid:373)e(cid:374)ts (cid:449)ith (cid:373)ild te(cid:373)pe(cid:396)atu(cid:396)e a(cid:374)d ph (cid:894)(cid:862)ph(cid:455)siologi(cid:272)al (cid:272)o(cid:374)ditions(cid:863)) With the e(cid:454)(cid:272)eptio(cid:374) of (cid:272)atal(cid:455)ti(cid:272) nas (cid:894)(cid:862)(cid:396)i(cid:271)oz(cid:455)(cid:373)es(cid:863)(cid:895), all e(cid:374)z(cid:455)(cid:373)es a(cid:396)e p(cid:396)otei(cid:374)s. Most enzymes catalyze the transfer of electrons, atoms or functional groups. They are therefore classified according to the type of transfer reaction, the group donor and the group receptor. Many enzyme names have the suffi(cid:454) (cid:862)-ase(cid:863): e. g. , dna polymerase catalyzes the polymerization of dna (addition of nucleotides to a. Dna strand: e. g. , urease catalyzes the hydrolysis of urea. Enzymes enhance rates of rea(cid:272)tio(cid:374) (cid:271)y lo(cid:449)eri(cid:374)g g , the a(cid:272)ti(cid:448)atio(cid:374) e(cid:374)ergy for the tra(cid:374)sitio(cid:374) state .