Enzymes are everywhere!
Vipers: Lowering your blood pressure since 1981
It could kill you: Most vipers are scary enough as is, but jararaca vipers are venomous to boot. But what's truly fascinating is the unique way their venom works. Unlike a traditional toxin, viper venom functions by preventing the blood from clotting, meaning the snakes actually kill their victims by causing them to bleed to death. But it just might cure you: Lucky for us, slow-clotting blood isn't always a bad thing. Researchers have found that small doses of viper venom can prevent arteries from hardening, thus stopping the kinds of blood clots that commonly occur in cardiac patients. In fact, jararaca viper venom (or at least a synthesized version of it) is a key ingredient in most of today's ACE inhibitors.
Introduced in 1981, ACE inhibitors are drugs that work by slowing down the body's angiotensin converting enzyme (ACE). When left untreated, the ACE enzyme can produce a peptide that causes muscle constriction around blood vessels. That kind of constriction can set off a chain reaction whereby a person's blood vessels narrow and his or her blood pressure shoots through the roof, leading to greater risk of heart attack and other ailments. Because the ACE inhibitors can stop this domino effect, they're frequently used to treat millions of men and women with high blood pressure.
The Renin – Angiotensin – Aldosterone System. Angiotensinogen (14 amino acids), the precursor of all angiotensin peptides, is synthesized by the liver. In the circulation, it is cleaved by renin, forming angiotensin I. In turn, angiotensin I (10 amino acids) is cleaved by angiotensin-converting enzyme (ACE), which is bound to the cells lining the blood vessel, to form angiotensin II (8 amino acids). In the adrenal glands, angiotensin II stimulates the production of aldosterone. Aldosterone raises blood pressure by prompting the kidneys to retain more salt. Used with permission from the New England Journal
1. What does ACE stand for?
2. What does an enzyme do?
3. What reaction does the ACE speed up?
4. Why do some drugs contain ACE inhibitors?
5. Why does the jararaca viper’s venom contain an ACE inhibitor?
Now Find Your Own!
· Choose an organ of the human body and research an associated enzyme (ex. Heart enzymes)
o Find the name (usually end in –ase) and function (usually build or break down)
o Find or draw a picture of the enzyme at work
o Find a disease that is associated with an error in this enzyme
o Find treatments used to overcome this disease