Vitamin K (VK) is a crucial cofactor involved in the blood clotting process. Specifically, it is essential for the modification of certain proteins by gamma-carboxylating glutamic acid residues.
The Role of Vitamin K
The reference material explains that Vitamin K (VK) is needed to convert 10-12 glutamic acid residues on the NH2-terminal of precursor coagulation proteins into their active form, gamma-carboxyglutamic acid. This conversion is carried out by a VK-dependent gamma-glutamyl carboxylase.
In simpler terms:
- Vitamin K acts as a helper molecule (cofactor): It facilitates a chemical reaction necessary for blood clotting.
- It modifies proteins: Specifically, it changes the structure of some proteins involved in coagulation.
- This modification is essential for these proteins to work: Without Vitamin K, these proteins cannot trigger the blood clotting cascade effectively.
Key Points
- Vitamin K (VK) is not just one substance; there are different forms of it (e.g., K1, K2).
- It's primarily known for its role in blood coagulation, but it also plays roles in bone health.
- A deficiency in Vitamin K can lead to increased bleeding risk.
- Sources of Vitamin K include green leafy vegetables, some fruits, and gut bacteria.
Summary Table
| Aspect | Description |
|---|---|
| Role | Cofactor in the gamma-carboxylation of glutamic acid residues on coagulation proteins. |
| Function | Enables the transformation of precursor coagulation proteins into their active form, gamma-carboxyglutamic acid, through the action of gamma-glutamyl carboxylase. |
| Importance | Vital for proper blood clotting and some aspects of bone metabolism. |
| Consequences of deficiency | Can lead to increased risk of bleeding. |
