Yes, MYCOPLASMAS is a Scrabble word!

Letter values in Scrabble US: M 3, Y 4, C 3, O 1, P 3, L 1, A 1, S 1, M 3, A 1, S 1.

Is it a valid word?

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

any of a group of small parasitic bacteria that lack cell walls and can survive without oxygen; can cause pneumonia and urinary tract infection