RT Journal Article
SR Electronic
T1 Using large-scale mutagenesis to guide single amino acid scanning experiments
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 140707
DO 10.1101/140707
A1 Vanessa E. Gray
A1 Ronald J. Hause
A1 Douglas M. Fowler
YR 2017
UL http://biorxiv.org/content/early/2017/05/22/140707.abstract
AB Alanine scanning mutagenesis is a widely-used method for identifying protein positions that are important for function or ligand binding. Alanine was chosen because it is physicochemically innocuous and constitutes a deletion of the side chain at the β- carbon. Alanine is also thought to best represent the effects of other mutations; however, this assumption has not been formally tested. To determine whether alanine substitutions are always the best choice, we analyzed 34,373 mutations in fourteen proteins whose effects were measured using large-scale mutagenesis approaches. We found that several substitutions, including histidine and asparagine, are better at recapitulating the effects of other substitutions. Histidine and asparagine also correlated best with the effects of other substitutions in different structural contexts. Furthermore, we found that alanine is among the worst substitutions for detecting ligand interface positions, despite its frequent use for this purpose. Our work highlights the utility of large-scale mutagenesis data and can help to guide future single substitution mutational scans.