When a cofactor binds to an enzyme it changes the shape of the active site slightly so it's just the right fit for the substrate. Vitamin C is a classic example of a cofactor. It's essential for the formation of collagen, a protein that acts like fibreglass reinforcement for our bodies.
Collagen keeps our skin firm, helps hold our organs together and forms the scabby scaffolding that new skin grows on after we're wounded. The key to collagen's strength is its shape — it's made up of fibres twisted together like rope. A bunch of enzymes are involved in making and twisting collagen, and one of those enzymes needs a molecule of vitamin C to do its job. The vitamin C locks onto the enzyme's active site, changing its shape so it's a better fit for the collagen molecule substrate.
The enzyme makes a chemical change in the collagen to give it a nice three-ply twist. Without vitamin C, the enzyme can't get a hold on the collagen, and the resulting fibres come out a little frayed. And without top shelf collagen our wounds don't heal properly, giving us gums and complexions that only the mother of an 18th century sailor could love.
The B-group vitamins all act in a similar way, whipping enzyme active sites into shape. They're cofactors in of most of our cells' everyday reactions — releasing energy from food, making and breaking proteins, fats and carbohydrates and building DNA. And without vitamin K as a cofactor the enzymes that clot our blood just can't work. But it's not just vitamins that make good cofactors — minerals do it too. A lot of the minerals we eat are metals, so they always have a positive charge when they dissolve in our bodies.
And slotting a small positive charge in just the right spot can turn an enzyme's active site on in a jiffy. Magnesium — the stuff that burns in birthday sparklers — is a cofactor for hundreds of enzymes. It's essential for everything from building DNA and proteins to storing energy and making nerve signals and muscle contractions.
And while we may not have heard of manganese, molybdenum and selenium, there are enzymes that just don't work without them, and neither would we. But rejigging enzymes isn't the only job in town for vitamins - vitamin A and D work at an even more basic level. They act as hormones that directly regulate our genes.
When sunlight hits your skin, UV rays convert some cholesterol into vitamin D. It's the only vitamin we can make ourselves, so we only need it from food if we're taking slip-slop-slap to the extreme. Vitamin D cholecalciferol is the keeper of calcium levels in our blood and our bones.
Those switches make our cells produce the proteins that increase calcium in our blood, by absorbing more calcium from our food or dragging it from our bones. If you're not getting or making enough vitamin D, you're not making these proteins so your body can't absorb enough calcium from your food.
Blood takes priority over bone so other hormones will leach calcium from your skeleton. Antioxidant ; part of an enzyme needed for protein metabolism; important for immune system health; aids in iron absorption.
Found only in fruits and vegetables, especially citrus fruits, vegetables in the cabbage family, cantaloupe, strawberries, peppers, tomatoes, potatoes, lettuce, papayas, mangoes, kiwifruit. Fat-soluble vitamins are stored in the body's cells and are not excreted as easily as water-soluble vitamins. They do not need to be consumed as often as water-soluble vitamins, although adequate amounts are needed. If you take too much of a fat-soluble vitamin, it could become toxic.
A balanced diet usually provides enough fat-soluble vitamins. You may find it more difficult to get enough vitamin D from food alone and may consider taking a vitamin D supplement or a multivitamin with vitamin D in it. Talk to your health care provider about the right supplement for you. Needed for vision, healthy skin and mucous membranes, bone and tooth growth, immune system health.
Vitamin A from animal sources retinol : fortified milk, cheese, cream, butter, fortified margarine, eggs, liver. Beta-carotene from plant sources : Leafy, dark green vegetables; dark orange fruits apricots, cantaloupe and vegetables carrots, winter squash, sweet potatoes, pumpkin.
Needed for proper absorption of calcium ; stored in bones. Egg yolks, liver, fatty fish, fortified milk, fortified margarine. When exposed to sunlight, the skin can make vitamin D. Polyunsaturated plant oils soybean, corn, cottonseed, safflower ; leafy green vegetables; wheat germ; whole-grain products; liver; egg yolks; nuts and seeds.
Leafy green vegetables such as kale, collard greens, and spinach; green vegetables such as broccoli, Brussels sprouts, and asparagus; also produced in intestinal tract by bacteria. This information does not replace the advice of a doctor. For example, aspartate aminotransferase is an enzyme that transfers amines between amino acids.
Each copy of the enzyme contains two vitamin B6 molecules, and without these molecules the enzyme cannot do anything. One use of Vitamin C is in the formation of collagen. Collagen is produced by special ribosomes in certain cells, and then exported from the cells to form collagen networks.
During the process of collagen formation, the body must manufacture hydroxylproline from the amino acid proline. Vitamin C is essential to this reaction. Without vitamin C, collagen cannot be produced -- the first signs of this are very weak and easily broken blood vessels and loose teeth which are held in their sockets by collagen.
The body is able to store some vitamins, such as vitamin A up to a year's supply is stored in your liver. Other vitamins need to be re-supplied frequently. Sign up for our Newsletter!
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