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Published on: July 14, 2015
The ST Pinch: A side chain-to-side chain hydrogen-bonded motif
Martha G Bomar1, Upadhyayula S Raghavender, Alexander W I Spindel
1Center for Advanced Drug Research, SRI International, Harrisonburg, Virginia 22802, USA.
Abstract:
The ST Pinch is a 12-membered hydrogen-bonded motif (Ser/Thr-Xaa-Ser/Thr) involving the side chain oxygen atoms of two Ser/Thr residues. We identified the ST Pinch in 104 proteins in a database containing high-resolution crystal structures. Conformational analysis of the ST Pinch in these proteins points to specific preferences for the Xaa residue and a high propensity of this residue to adopt positive φ angles. Our results suggest that this motif serves as a linker of secondary structural elements within proteins and is a new addition to the existing list of short hydrogen bond-stabilized motifs in proteins.
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