in this video, we're going to talk about the trip operations specifically in the presence of tryptophan. And so when tryptophan, this amino acid is really, really abundant and prevalent and found in high levels in the environment, then the cell does not really have a need to synthesize its own tryptophan. And so the trip Oberon which has genes for synthesizing its own tryptophan, it's going to be inactive when there is plenty of tryptophan that is abundant in the environment. And so what happens is tryptophan is going to act as a co repressor to the repressor protein. And so the co repressor tryptophan is going to bind to and activate the Trip repressor protein. And so if we take a look at our image down below, we can see that cellular tryptophan is going to co repress the trip operation when it's readily abundant for the cell. And so we're specifically looking at the trip Operandi in the presence of tryptophan. And so when tryptophan is really, really abundant and prevalent, then the cell has no need to synthesize its own tryptophan. And so it needs to shut down the trip opera. And so this is how it works. The trip regulatory gene which encodes Trip our which is our suppressor protein which has its own promoter, it's going to be transcribed and translated into an inactive trip repressor. And the inactive trip repressor is only going to be activated in the presence of tryptophan. And so when tryptophan is really really, really abundant, then there's going to be tryptophan available to bind to the inactive trip repressor and the tryptophan is going to act as the co repressor here. So the tryptophan is acting as the co repressor. And so the trip to fan co repressor is going to bind to the inactive trip our repressor. And that is going to form an active trip repressor and notice the active trip repressor is capable of binding to the trip operator. And when it's bound to the trip operator it's going to block and inhibit transcription, turning off the trip operandi. And so it's going to prevent the RNA polymerase from binding to the promoter and proceeding with transcription. And so basically what we're seeing here is again when the trip operation is in the presence of tryptophan. When tryptophan is readily available then the cell has no need to create its own tryptophan. And so it's going to shut down the trip operandi through this mechanism where tryptophan acts as a co repressor. And so this here concludes our brief introduction to what happens to the trip papa ran in the presence of tryptophan. And so moving forward we'll be able to talk about the trip operation in the absence of tryptophan. So I'll see you all in that video