Bio180Physio - Lec1 Protein Interactions

name 4 common organic molecules in the body

carbohydrates, lipids, proteins, nucleic acids

draw an amino acid and list the three side chain variants

carbon w/ amine, R side chain, carboxylic acid, and H

polar, nonpolar, and ionized R groups

explain how amino acids connect

peptide bond; the H in amine and HO in carboxylic acid → -H20 so that the N and C bind

explain primary structure

long but plain sequence of amino acids

explain secondary structure

proteins start folding into alpha helix or beta-pleated sheets, connected by hydrogen bonding

explain tertiary structure

driven by interactions between the R groups, actually becomes functional because the folding makes active sites

structurally solid enough to stay stable, but flexible enough to function

quaternary structure

separate chains within quaternary structure called “subunit” w/ its own primary/secondary/tertiary status, bound by noncovalent bonds

ligand

ion or molecule that binds to protein by electric or hydrophobic interactions

binding is generally weak → easy to break

Brownian motion - definition and its application

random movement of molecules → natural and random binding/unbinding

protein binding depends on two things

conformation and charge

name 3 properties of binding sites & explain them

specificity = how restrictive binding site is, higher specificity → more picky

affinity = how strongly protein binds to ligand, eg. more charged → higher affinity

saturation= % of binding sites used up

explain functional and regulatory binding sites

functional - triggers the physiological function

regulatory - presence changes the functional binding sites, inhibition or activation

explain the two types of regulation

covalent binding and allosteric binding

define catabolism and anabolism

catabolism - breakdown of organic molecules

anabolism - synthesis of organic molecules

explain and draw a diagram on how catalysts work

lower activation energy, not consumed in reaction

explain cofactor and coenzymes

cofactor - inorganic elements, simple bit necessary for enzyme to be functional

coenzyme - complex organic molecules acting as a mobile carrier, helps enyme run

explain how regulating enzymes → regulates reactions

concentration of enzymes regulates the reaction

explain the energy output and equilibrium of REVERSIBLE reactions in the body

reversible → release little energy

in EQ, products slightly more than reactants

explain the energy output and equilibrium of IRREVERSIBLE reactions in the body

release high energy

at EQ → ALL reactants turn into products