Molecular recognition of sulfotyrosine and phosphotyrosine by the Src homology 2 domain.

We study molecular recognition of two closely resembling posttranslational modification products, phosphotyrosine (pTyr) and sulfotyrosine (sTyr). The differences in charge, size, and binding geometry of pTyr and sTyr are the main recognition elements. Protein engineering can be applied to alter the specificity and strength of the recognition.