7rtx

Publication Abstract from PubMed

Actophorin, a protein that severs actin filaments isolated from the amoeba Acanthamoeba castellanii, was employed as a test case for crystallization under microgravity. Crystals of purified actophorin were grown under microgravity conditions aboard the International Space Station (ISS) utilizing an interactive crystallization setup between the ISS crew and ground-based experimenters. Crystals grew in conditions similar to those grown on earth. The structure was solved by molecular replacement at a resolution of 1.65 A. Surprisingly, the structure reveals conformational changes in a remote beta-turn region that were previously associated with actophorin phosphorylated at the terminal residue Ser1. Although crystallization under microgravity did not yield a higher resolution than crystals grown under typical laboratory conditions, the conformation of actophorin obtained from solving the structure suggests greater flexibility in the actophorin beta-turn than previously appreciated and may be beneficial for the binding of actophorin to actin filaments.

Improved resolution crystal structure of Acanthamoeba actophorin reveals structural plasticity not induced by microgravity.,Quirk S, Lieberman RL Acta Crystallogr F Struct Biol Commun. 2021 Dec 1;77(Pt 12):452-458. doi:, 10.1107/S2053230X21011419. Epub 2021 Nov 11. PMID:34866600^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.