BIOC 4580 Study Guide - Midterm Guide: Major Facilitator Superfamily, Lactose Permease, Electrochemical Gradient

• School: University of Guelph
• Department: Biochemistry
• Course: BIOC 4580
• Professor: George Harauz

Document Summary

Active transport uses energy (the main currency is atp) to transport substances against their concentration or electrochemical gradient. Secondary active transporters piggyback on ion (usually h+ or na+) or other gradients formed by active transporters. We will discuss 2 examples of secondary active transport: the e. coli lactose permease & the mammalian sodium-glucose symporter. There are p-, v-, f-, and abc-types of atpases that perform active transport. We will discuss the na+k+-atpase (p-type), the p-glycoprotein multidrug transporter (abc-type) in some detail, with broad overview of f-types and v-types. Transport energy can derived from: atp, light, electron transfer, h+ pumping and coupled transport. Example: lactose permease in e. coli: a. k. a. Lacy is coupled to proton transport (prototype for proton-driven cotransporters) Maintaining a proton gradient requires a lot of energy on its own, but it is used to create proton transport. Rocking motion between 2 domains driven by substrate binding & protein movement (rocking bananas)