transferase activity, transferring nitrogenous groups peptidyl-cysteine S-nitrosylase activity https://github.com/geneontology/go-ontology/issues/23262 protein nitrosylase activity 2010-11-16T09:49:26Z S-nitrosylase activity bf RHEA:66684 molecular_function GO:0035605 RHEA:67152 Catalysis of the transfer of a nitric oxide (NO) group to a sulphur atom within a cysteine residue of a protein. This term should not be used to annotate the nitrosylating action of nitric oxide synthase (NOS) if the nitroso group is synthesized directly on the substrate. catalytic activity, acting on a protein