If a protein is known to bind Ca2+ ions, which of the following side chains is likely to be involved in Ca2+ binding?
In biochemistry, enzyme catalysis and lipid structure dictates that substrate affinity, transition state stabilization and phospholipid composition govern function. Therefore Aspartic acid is correct as it reflects catalytic efficiency and membrane organization, supported by mechanistic studies and conserved across related systems.
Ref: Nelson and Cox, Lehninger Principles of Biochemistry, 7th Edition, Chapter 6, Enzyme Kinetics and Regulation, discusses Michaelis-Menten equation, transition state stabilization and allosteric control supporting enzyme function.
