Tag: collagen

Yes Virginia, vegan collagen is real!

KindofStephen

When Algenist launched the Genius Liquid Collagen with “vegan collagen” my first thought was, “What? Only animals have collagen!”⁣

Well, you’re looking at a vial of collagen that has been produced by yeast.⁣
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Collagen is the main structural protein in animals, there are over 28 types of collagen. Type I collagen makes up about 90% of the collagen found in humans.
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Collagen gives our skin its strength, flexibility, structure, and durability. Collagen is a triple helix, made of three coils of amino acids wrapped around each other. This coiled structure allows collagen to be stretched without breaking.⁣ Check out an earlier post I wrote about collagen for more information.
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Plants and microbes don’t normally make collagen, but turns out they can! With some help from science, of course.⁣
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Vegan collagen is often produced from modified yeast and bacteria, scientists have been doing this for decades. Collagen can also be produced by modified plants, like the tobacco plant.⁣
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In one method, 4 genes that encode for the building blocks of collagen were added into a yeast’s genetic structure. The human genes were expressed in the modified yeast and they started producing the building blocks of human collagen type I. These building blocks were collected and treated with pepsin (a digestive enzyme), which assembled them into collagen and broke down any material that didn’t form properly.⁣
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Why make microbe or plant-based collagen? It’s often purer and it doesn’t rely on animals. Though it occurs rarely, animal collagen can cause foreign body or allergic reactions. Animal sources of collagen are fish, pigs, and cows.⁣
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Collagen is useful as a moisturizer for the skin, but also has medical applications. Collagen is used as a material for cosmetic filler, as carriers in drug delivery, as sutures, and as scaffolds for tissue engineering. Collagen can also be modified and used for neuron regeneration, blood vessel repair, bone regeneration, wound healing, and more!⁣

M Nokelainen, High‐level production of human type I collagen in the yeast Pichia pastoris, Yeast, 2001. DOI: 10.1002/yea.730

A quick look at collagen

KindofStephen

Collagen, you’ve seen it in your skincare products and have probably eaten it at some point (Yay for artificially-coloured and jiggly gelatin). But what is it?

Collagen is composed of a triple helix, three strands of proteins made up of joined amino acids wrapped around each other. The main amino acid constituents of these proteins are glycine, proline, hydroxyproline, lysine, and hydroxylysine. The unique chemical structure of the amino acids helps form the shape and structure that their compounds make.

There are many types of collagen, which differ in their amino acid composition. Type I collagen is the most abundant in the human body, and Type I, III, IV, and others are found in our skin. In our body, multiple strands of collagen are found bundled together in fibrils.

You may have heard that ascorbic acid or Vitamin C is crucial in the formation of collagen, but how? Ascorbic acid is used in the conversion of proline to hydroxyproline along with oxygen, and alpha-ketoglutarate. The reaction is catalyzed or sped up by the enzyme prolyl hydroxylase and an iron. Similarly, it is needed in the hydroxylation of lysine to hydroxylysine by the enzyme lysyl hydroxylase.

Collagens are naturally glycosylated, meaning they have sugar molecules bound to them – they are found attached to the lysine and hydroxylysine molecules by the enzymes galactosyltransferase and glucosyltransferase. While this glycosylation is not fully understood, they seem important in forming and retaining the structure of the collagen. You may have heard of glycation or advanced glycation endproducts (AGEs), this happens when excessive sugar molecules are bound to the collagen non-enzymatically and can affect its structure, function, and flexibility.

The additional -OH (hydroxy) group on the hydroxyproline helps water molecules bind tightly to collagen. The coiled structure of collagen’s triple helix gives it impressive tensile strength and allows it to stretch when forces are applied. When too much force is applied the triple helix structure can become disorganized and damaged, no longer able to return to its triple helix form.

Experiments, where collagen was exposed to UV radiation in vitro, have shown that free radicals generated from the UV energy can cleave or break apart some of the bonds holding the amino acids together. When enough bonds are broken the triple helix structure can no longer be maintained and the collagen fibre loses its shape and function. Adding ascorbic acid to the solution of collagen, when it was exposed to UV, reduced some of the free radicals produced – leading to fewer bonds breaking and structure disruption. This may highlight one of the ways naturally present antioxidants in the skin help us defend against the environment.

N. Metreveli, L. Namicheishvili, K. Jariashvili, G. Mrevlishvili, A. Sionkowska. Mechanisms of the influence of UV irradiation on collagen and collagen-ascorbic acid solutions. International Journal of Photoenergy (2006), DOI: 10.1155/IJP/2006/76830

Duer Research Group. Collagen glycation and diabetes. Website, URL: https://www.ch.cam.ac.uk/group/duer/research/collagen-glycation-and-diabetes

A. Masic, L. Bertinetti, R. Schuetz, S.W. Chang, T.H. Metzger, M.J. Buehler, P. Fratzl. Osmotic pressure induced tensile forces in tendon collagen. Nature Communications (2015), DOI: 10.1038/ncomms6942

J.M. Waller, H.I. Maibach. ge and skin structure and function, a quantitativeapproach (II): protein, glycosaminoglycan, water, andlipid content and structure. Skin Research and Technology (2006), DOI: 10.1111/j.0909-752X.2006.00146.x