So this is ultimately step number one that we have here. Now, step number two is catalyzed by an enzyme we call the Ubiquitin conjugating enzyme conjugating enzyme or E Two. And what this enzyme ultimately does is it transfers that Ubiquitin from the enzyme E One onto the enzyme E Two. So just like the enzyme E One contains this sulfidel group in the active side, enzyme Two also contains a cysteine residue that contains that sulfhydrol group. And so we simply have a shutter link, a transferring of the Ubiquitin from enzyme One to enzyme two. So we see that the activated version of Ubiquitin that we formed in step number one is now transferred onto the second enzyme by attaching it onto the cysteine residue of enzyme Two, E Two.