Novel His-tag Variants for Insertion Inside Polypeptide Chain.

His-tags are protein affinity tags ubiquitously used due to their convenience and effectiveness. However, in some individual cases, the attachment of His-tags to a protein's N- or C-termini resulted in impairment of the protein's structure or function, which led to attempts to include His-tags inside of polypeptide chains. In this work, we describe newly designed internal His-tags, where two triplets of histidine residues are separated by glycine residues to avoid steric hindrances and consequently minimize their impact on the protein structure.

Recognition of γ-Subunit by β-Subunit in Translation Initiation Factor 2. Stabilization of the GTP-Bound State of I/F 2 in Archaea and Eukaryotes.

Eukaryotic and archaeal translation initiation factor 2 (e/aIF2) functions as a heterotrimeric complex. It consists of three subunits (α, β, γ). α- and β-subunits are bound to γ-subunit by hydrogen bonds and van der Waals interactions, but do not contact each other.