Sentence: Moreover , S118 of wild-type protein formed H-bonds with T134 and G135 but these interactions were lost in PRRSVAV ( S118A ) and PRRSVES ( S117A ) indicating that the substitution of important H-bond interaction in PRRSVAS ( S118A ) and PRRSVES ( S117A ) affected the flexibility around the catalytic triad , conformation and proteolytic activity. 
 Section: finding