Complete this sudoku-inspired puzzle to find the holder of an official chemistry role in the UK 

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 rearragned to give the surname of an official scientific adviser to the UK government.

This week’s letters are: A B E K M O R S Y