Reaction of sulfenyl halides with cytochrome c. A novel method for heme cleavage

Nay 1'973 1, lntroduelion The h.eme group of y~oc~rome c is linked ~o .the polypep~ide ehAn by thieeth,er b.rAges 11 ]. Me~ods presently used for home cleavage involve the use of heawj metals ~uth as silver ,and m.ercury I2, 3], performic acid [4], or, as recently reported, iodine mad cyanogen bromide I5]. Attempting to selectively modify No single ~ryp~ophan residue of horse heart ytochlome c by sulfeny] halide~ .~], we found tha~ ~h~, ~-eagen~ alS~ a]lOv~ a rapid and quanIi~a.tiv-e cleavage of ~e tlaioethe~ bonds linking tlae h.eme to ~,e p~o!ein.