Scientists discover how a key enzyme heals sun-damaged DNA

Ohio State University scientists discover the enzyme that can heal sun-damaged skin in less than a second. In the future, we could use sunscreen that treats DNA and change the treatment for skin cancer.
Written by Boonsri Dickinson, Contributing Editor

Imaging lathering yourself with subatomic sunscreen before you venture out into the sun. The sunscreen could do more than just protect your skin from harmful ultraviolet light — it could fix your sun-damaged skin instantly.

However, the pro-active skin care products are a bit futuristic. But the idea of using products that can rapidly repair DNA might one day be possible thanks to a laboratory discovery made by Ohio State University scientists.

The researchers witnessed for the first time how the enzyme photolyase repairs sun-damaged DNA — and it does so in a few billionths of a second.

The thing is, this enzyme is found in plants and animals (except mammals).

Bacteria has this protection, but we don't. So when our skin is exposed to the sun, the ultraviolet light makes chemical bonds form in the wrong places along the DNA.

Sun-damaged skin is more than a superficial problem.

What happens on vacation, doesn't necessarily stay there. Our choices we make about our exposure to the sun is a major health issue.

As you probably already know, chronic sun damage causes DNA mutations that can lead to skin cancer and other diseases.

The experiments didn't take place on a beach or anywhere like that.

In a lab at Ohio State, the physicist and chemist Dongping Zhong synthesized DNA and gave it an artificial dose of sunshine by applying ultraviolet light. After the DNA appeared to have the same hallmarks of sun damaged skin, Zhong added the enzyme to the mix.

That's when the scientists stalked the enzyme's every atomic move. Zhong used ultrafast light pulses to take a series of pictures to see how the photolyase worked on the DNA. The enzyme basically gets rid of the wrong chemical bonds that formed during sun exposure and quickly makes the bonds revert back into how they were before during the sun damaged it.

But it doesn't stop there. The photolyase then gets its photon and electron back because original bond doesn't need it anymore. This way, the enzyme can continue to repair other damaged DNA.

“It sounds simple, but those two atomic particles actually initiated a very complex series of chemical reactions,” Zhong said in a statement. “People have been working on this for years, but now that we’ve seen it, I don’t think anyone could have guessed exactly what was happening,”

While we have some other enzymes that can heal damaged DNA, it doesn't quite work as well as the photolyase.

In the future, I wouldn't be surprised to see the shelves at a local drugstore full of skin care products capable of healing our sun-damaged DNA skin, made with the special ingredients: two subatomic particles.

Until then, use regular sunscreen and umbrella chairs for added protection.

If you're thinking of emailing Zhong to ask him which lamp to buy, don't. Someone already asked him that. Humans don't have the enzyme, he explained to the curious email correspondent. Now if you have fish, that's another story. In that case, use visible blue light in the fish tank to undo any previous UV damage.

This post was originally published on Smartplanet.com

Editorial standards