Acs Biochemistry Exam 2024-2025

Henderson-Hasselbach Equation - ANSWER--pH = pKa + log ([A-] / [HA]) FMOC Chemical Synthesis - ANSWER--Used in synthesis of a growing amino acid chain to a polystyrene bead. FMOC is used as a protecting group on the N- terminus. Salting Out (Purification) - ANSWER--Changes soluble protein to solid precipitate. Protein precipitates when the charges on the protein match the charges in the solution. Size-Exclusion Chromatography - ANSWER--Separates sample based on size with smaller molecules eluting later. Ion-Exchange Chromatography - ANSWER--Separates sample based on charge. CM attracts +, DEAE attracts -. May have repulsion effect on like charges. Salt or acid used to remove stuck proteins. Hydrophobic/Reverse Phase Chromatography - ANSWER--Beads are coated with a carbon chain. Hydrophobic proteins stick better. Elute with non-H-bonding solvent (acetonitrile). Affinity Chromatography - ANSWER--Attach a ligand that binds a protein to a bead. Elute with harsh chemicals or similar ligand.SDS-PAGE - ANSWER--Uses SDS. Gel is made from cross-linked polyacrylamide. Separates based off of mass with smaller molecules moving faster. Visualized with Coomassie blue. SDS - ANSWER--Sodium dodecyl sulfate. Unfolds proteins and gives them uniform negative charge. Isoelectric Focusing - ANSWER--Variation of gel electrophoresis where protein charge matters. Involves electrodes and pH gradient. Protein stops at