Figure 4.
Proposed model of the pertussis-like toxins transfer target. a, structure of opsin in complex with the C terminus of transducin (Scheerer et al. (38), Protein Data Bank code 3DQD); their K345L mutant was reverted to lysine for this figure. Gαi3 is shown in teal; the position of the C terminus and ADP-ribosylated residues discussed in text are shown. The plasma membrane and GPCR (green) are at the top. b, ADP-ribosyltransferase assays using EcPltA or pertussis toxin in which potential acceptor cysteines within Gαi3ΔN were mutated to serine; or c, following iodoacetamide and lysine methylation; d, mutation of Lys-345; or e, Asn-346 and Asn-347 to alanine.