( Proteins ( ( are ( ( long ( chain molecules ) ) ( of ( ( amino acids ) ( with ( ( a backbone ) ( of ( covalently ( bonded atoms ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNPS Proteins)) (VP (VBP are) (NP (NP (JJ long) (NN chain) (NNS molecules)) (PP (IN of) (NP (NP (JJ amino) (NNS acids)) (PP (IN with) (NP (NP (DT a) (NN backbone)) (PP (IN of) (NP (JJ covalently) (VBN bonded) (NNS atoms))))))))) (. .)))
Proteins are long chain molecules of amino acids with a backbone of covalently bonded atoms.
(ROOT (S (NP (NNPS Proteins)) (VP (VBP are) (NP (NP (JJ long) (NNS chains)) (PP (IN of) (NP (JJ amino) (NNS acids))))) (. .)))