To understand better how the packing of side chains within the core influences protein structure and stability, the crystal structures were determined for eight variants of T4 lysozyme, each of which contains three to five substitutions at adjacent interior sites. Concerted main-chain and side-chain displacements, with movements of helical segments as large as 0.8 angstrom, were observed. In contrast, the angular conformations of the mutated side chains tended to remain unchanged, with torsion angles within 20 degrees of those in the wild-type structure. These observations suggest that not only the rotation of side chains but also movements of the main chain must be considered in the evaluation of which amino acid sequences are compatible with a given protein fold. Study holds ProTherm entries: 1162, 1163, 1164, 1165, 1166, 1167, 1168, 1169, 1170, 13570, 13571, 13572, 13573, 13574, 13575, 13576, 13577 Extra Details: ddG was measured at 51.5 degrees C T4 lysozyme; flexibility; protein structure; packing
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:16 p.m.
|Number of data points||17|
|Proteins||Endolysin ; Endolysin|
|Assays/Quantities/Protocols||Experimental Assay: Tm buffers:Potassium phosphate: - ; Experimental Assay: ddG ; Experimental Assay: Tm buffers:Potassium phosphate: 20 mM|
|Libraries||Mutations for sequence MNIFEMLRIDEGLRLKIYKDTEGYYTIGIGHLLTKSPSLNAAKSELDKAIGRNCNGVITKDEAEKLFNQDVDAAVRGILRNAKLKPVYDSLDAVRRCALINMVFQMGETGVAGFTNSLRMLQQKRWDEAAVNLAKSRWYNQTPNRAKRVITTFRTGTWDAYKNL|