( ( Profiles ( for ( ( ( a ( single ( polypeptide chain ) ) ) or ) ( ( difference profiles ) ( for ( two ( aligned ( polypeptide chains ) ) ) ) ) ) ) ) ( ( may ( be examined ) ) . ) )
(ROOT (S (NP (NP (NNS Profiles)) (PP (IN for) (NP (NP (DT a) (JJ single) (NN polypeptide) (NN chain)) (CC or) (NP (NP (NN difference) (NNS profiles)) (PP (IN for) (NP (CD two) (JJ aligned) (NN polypeptide) (NNS chains))))))) (VP (MD may) (VP (VB be) (VP (VBN examined)))) (. .)))
Profiles for a single polypeptide chain or difference profiles for two aligned polypeptide chains may be examined.
(ROOT (S (NP (NNP Insulin)) (VP (VBZ is) (VP (VBN made) (PRT (RP up)) (PP (IN of) (NP (CD two) (JJ polypeptide) (NNS chains))))) (. .)))