Chemistry wordoku #154

Solve this wordoku in the same way as a sudoku with letters instead of numbers (each of the nine letters in each row, column and nine-square cell). Once solved, one of the overall diagonals can be rearranged to give the surname of a chemist and biologist whose research at the Massachusetts Institute of Technology in the US includes protein modification, with special emphasis on N–linked protein glycosylation.

This week’s letters are: A E I L M P R S T