Yes, CATGUT is a Scrabble word!

Letter values in Scrabble US: C 3, A 1, T 1, G 2, U 1, T 1.

Is it a valid word?

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

perennial subshrub of eastern North America having downy leaves yellowish and rose flowers and; source of rotenone
a strong cord made from the intestines of sheep and used in surgery

Also: goat's rue, wild sweet pea, tephrosia virginiana.