Biochemistry Review Primary Structure: Linear arrangement of AA acids coded in an organism’s DNA. Listed from N-terminus to C-terminus Stabilized by the formation of covalent peptide bonds between adjacent AA. Encodes all information needed for folding at all the higher levels. Secondary Structure: local structure of neighboring AA. Primarily the result of hydrogen bonding of intramolecular hydrogens between different residues. Alpha Helices: stabilized by intramolecular hydrogen bonds between the carbonyl oxygen and the amide hydrogen found four residues down. O-H bond. Tertiary Structure: the three-dimensional shape. Determined by hydrophobic interactions between R-groups. N-H and C=O bonds are attracted to hydrophobic groups, electrostatic interactions result in further stabilization. Hydrophilic R groups are on the outside, hydrophobic ones on the inside. Disulfide bonds are made between two adjacent cysteines that oxidize to form cystine. Create loops. Carbohydrate Metabolism Part 1: Glucose entry into most cells is driven by concentration and is independent of sodium (except in the digestive tract). Glut-2: low affinity transporter in hepatocytes (liver) and pancreatic cells. Primarily for storage. The liver will preferentially uptake excess glucose and store it. Glut-4: adipose tissue and muscle, responds to the glucose concentration in peripheral blood. The activity of this enzyme is increased by insulin Glycolysis:
