Open AccessStructure of a tropomyosin N‐terminal fragment at 0.98 Å resolution
Author(s) -
Meshcheryakov Vladimir A.,
Krieger Inna,
Kostyukova Alla S.,
Samatey Fadel A.
Publication year - 2011
Publication title -
acta crystallographica section d
Language(s) - English
Resource type - Journals
ISSN - 1399-0047
DOI - 10.1107/s090744491102645x
Subject(s) - tropomyosin , crystallography , crystal structure , chemistry , resolution (logic) , n terminus , coiled coil , c terminus , helix (gastropod) , actin , protein structure , peptide sequence , biology , amino acid , ecology , biochemistry , artificial intelligence , snail , computer science , gene
Tropomyosin (TM) is an elongated two‐chain protein that binds along actin filaments. Important binding sites are localized in the N‐terminus of tropomyosin. The structure of the N‐terminus of the long muscle α‐TM has been solved by both NMR and X‐ray crystallography. Only the NMR structure of the N‐terminus of the short nonmuscle α‐TM is available. Here, the crystal structure of the N‐terminus of the short nonmuscle α‐TM (αTm1bZip) at a resolution of 0.98 Å is reported, which was solved from crystals belonging to space group P 3 1 with unit‐cell parameters a = b = 33.00, c = 52.03 Å, α = β = 90, γ = 120°. The first five N‐terminal residues are flexible and residues 6–35 form an α‐helical coiled coil. The overall fold and the secondary structure of the crystal structure of αTM1bZip are highly similar to the NMR structure and the atomic coordinates of the corresponding C α atoms between the two structures superimpose with a root‐mean‐square deviation of 0.60 Å. The crystal structure validates the NMR structure, with the positions of the side chains being determined precisely in our structure.