The Journal of Biological Chemistry VOL. 289, NO. 38, pp. 26089–26106, September 19, 2014
Background: SENSITIVE TO FREEZING 2 (SFR2) is classified as a glycosyl hydrolase, and by using glycosyltransferase activity, it modifies membrane lipids to promote freeze tolerance.
Results: Although the active site of SFR2 is identical to hydrolases, adjacent loop regions contribute to its transferase activity.
Conclusion: Transferase activity evolved by modifications external to the core catalytic site.
Significance: Defined structure-function relationships will inform engineering of transferases and freeze tolerance.