( This ( ( reacts ( with ( ( the ( amine group ) ) ( of ( the ( N-terminal ( amino acid ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (VBZ reacts) (PP (IN with) (NP (NP (DT the) (JJ amine) (NN group)) (PP (IN of) (NP (DT the) (JJ N-terminal) (JJ amino) (NN acid)))))) (. .)))
This reacts with the amine group of the N-terminal amino acid.
(ROOT (S (NP (NNP Amino) (NNS acids)) (VP (VBP contain) (NP (PDT both) (NP (DT a) (JJ carboxylic) (JJ acid) (NN group)) (CC and) (NP (DT a) (-LRB- -LRB-) (NN n) (-RRB- -RRB-) (JJ amine) (NN group)))) (. .)))