... FEBSDiscussion The characterization of the SsAH enzyme describedhere strongly suggests that the Ser171–cisSer195–Lys96catalytic triad, similarly to other members of thisfamily, forms the ... suggests that, inaddition to the classical catalytic Ser-cisSer-Lys, a putative additionalCys-cisSer-Lys catalytic site, likely to be responsible for nitrile hydrolysis, is present in these proteins. ... (SP5).Some torsional space exploration of the side chain wasnecessary to avoid clashes with the Nd2 atom of Asn98.AcknowledgementsThis work is part of the ‘FANS’ project N°2881 fundedby the...