Yes, DENATURE is a Scrabble word!

Letter values in Scrabble US: D 2, E 1, N 1, A 1, T 1, U 1, R 1, E 1.

Is it a valid word?

DENATURE is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

add nonfissionable material to (fissionable material) so as to make unsuitable for use in an atomic bomb
modify (as a native protein) especially by heat, acid, alkali, or ultraviolet radiation so that all of the original properties are removed or diminished
make (alcohol) unfit for drinking without impairing usefulness for other purposes