Govt Exams
Molecular chaperones like Hsp70 and Hsp90 help nascent proteins fold into their correct three-dimensional structure and prevent inappropriate aggregation, essential for cellular proteostasis.
Aldolase requires a Zn²⁺ cofactor as part of its active site, which is crucial for substrate binding and catalysis in aldol condensation reactions.
An alpha-helix makes 3.6 residues per turn. Each C=O of residue n forms a hydrogen bond with the N-H of residue n+4, resulting in approximately 4 hydrogen bonds per turn.
In competitive inhibition, the inhibitor competes with substrate for the active site. The apparent Km increases (appears to require more substrate to reach Vmax), but true Vmax remains unchanged because the inhibitor can be outcompeted at high substrate concentrations.
Allosteric enzymes have regulatory sites distinct from active sites and show cooperativity, resulting in sigmoidal kinetics rather than hyperbolic kinetics seen in simple enzymes.
Lipase catalyzes the hydrolysis of ester bonds in lipids. Amylase acts on carbohydrates, protease on proteins, and nuclease on nucleic acids.
Extreme pH causes ionization of amino acid side chains and disruption of protein structure, leading to denaturation and loss of enzymatic activity.
Quaternary structure involves interactions between different polypeptide chains, not covalent peptide bonds. Only non-covalent interactions maintain quaternary structure.
Leucine, Isoleucine, and Valine are branched-chain hydrophobic amino acids typically buried in the interior of folded proteins.
Peptide bond formation is part of protein synthesis and structure, not denaturation. Denaturation involves disruption of secondary and tertiary structures.