Question: what is the difference between alpha and beta tubulin?
Answer: The key difference between Alpha and Beta Tubulin is that the alpha tubulin contains Asp-254 at the E-site while the beta-tubulin contains Lys-254 at the N-site. Apart from that, GTP is always attached to alpha-tubulin subunit, while at the beta-tubulin subunit, GTP is exchangeable for the microfilaments to polymerize.