... of parallel b strands associated to an antiparallel strand (b2) and is surrounded by helices (a1 , a2 , a3 , a7 and a8 ) The second domain consists of helices a4 , a5 and a6 all clustered on the top ... indicating that Rv1399c is composed of 22% of a- helices, 25% of b-strand and 39% of random coil The catalytic triad is located at the bottom of a small ˚ ˚ pocket, 20 A length and 10 A wide The pocket ... hydrolases (Fig 3) These enzymes share a functional catalytic triad made of a catalytic nucleophile serine, associated to a proton carrier histidine and a charge relaying aspartic (or glutamic) acid...