Phosphorylation introduces a negatively charged phosphate on the serine side chain. Aspartate has a negatively charged carboxylate and can mimic part of that electrostatic effect, so B is the intended replacement. Alanine removes the phosphorylation site without mimicking its charge, phenylalanine is hydrophobic, and lysine is positively charged. A phosphomimic is an approximation rather than a chemically identical phosphoserine.
More Cell Biology: Post-translational modifications, protein trafficking, cell death and autophagy, extracellular matrix questions
GATE 2024 BT Q17– Co-translational translocation of proteins is observed in .
GATE 2026 BT Q29– Which of the following is/are extra-cellular matrix protein(s)?
GATE 2023 BT Q21– Intracellular proteins are targeted for proteolytic degradation in proteasomes upon…
GATE 2022 BT Q43– The enzymes involved in ubiquitinylation of cell-cycle proteins are
GATE 2022 BT Q54– Which of the following statement(s) regarding trafficking in eukaryotic cells is(are)…
GATE 2021 BT Q22– The process supplying intracellular macromolecules for lysosomal degradation during…