 I know this won't matter to you or it makes sense to you because you may not be watching these in order, but this is the last video I'm making of the different types of antibiotics. I'm pretty excited. It's been a long one. There's lots of good antibiotics and I hope I have to make this list longer because we get new antibiotics that will help keep my kids and my future grandkids safe, right? So we are going to talk about an anti-metabolite drug that actually interferes with the production of mycolic acid. So mycolic acid is only going to be found in your acid-fast bacteria, which is they're called that because of the acid-fasting. And that would be the mycobacterium and the nocardia, which nocardia we rarely ever talk about as far as mycobacterial diseases, you really only have the two, mycobacterium tuberculosis causing TB and then mycobacterium lepre, which causes leprosy or Hansen's disease. So this antibiotic is selective against the mycobacterium, making it super, super important because tuberculosis is such a huge problem, a worldwide pandemic, so it's going to impact the production of cell walls, but just the cell walls that have a bunch of mycolic acid in it. There are certainly our side effects, but a couple of interesting things about this. Number one, treatment time is a long time, right? Six months are longer if you're treating TB or latent TB, six, nine, 12-month treatments. And the reason for that is because bacteria, as they divide, is when they become really vulnerable and when they can be killed. When they're making new cell walls or when they're producing proteins so that cells can divide, right? But mycobacteria are really, really slow-growing organisms, so they don't divide very quickly, and that's why it takes a long time. And any given day, you're not going to kill that many of them, so that's why the treatment time is going to be really long. You see here the example of the mycolic acid inhibitor would be isoniazid. So this is a very important antibiotic. This drug is usually used in combination with other drugs, so you've got streptomycin, as we mentioned, can be good against killing mycobacterium. We've also done a video on rifampin, so you see a combination therapy usually. But I do want to talk about one other combination you'll see, isoniazid is also often used with ethambutol, which is a different antibiotic, and we barely talk about it. And it's not a very good antibiotic, it's actually not super effective. But this is an interesting example of when we use a combination therapy. Isoniazid, on its own, is the more effective antibiotic. Having ethambutol can make it slightly more effective, but the main reason you do so is to slow resistance. I like to say that any time an organism evolves drug resistance, it's won the lottery. Well, if you throw two or more drugs at an organism, the hope is you're making it win the lottery two or three or four times, which means random mutations shouldn't cause problems. So one reason to use a combination therapy is because it's more effective. But also remember that a second reason to use a combination of drugs is to hopefully avoid issues with resistance. All right, so that is the mycolic acid inhibitors, isoniazid being the most important one there. I hope this helps. Have a wonderful day. Be blessed.