Featured Research

from universities, journals, and other organizations

Enzyme Discovery Sheds Light On Vitamin D

Date:
July 25, 2007
Source:
Queen's University
Summary:
Surprising findings have shed new light on how the "sunshine vitamin" D -- increasingly used to treat and prevent cancer and other diseases -- is broken down by our bodies. The researchers believe the hydroxylase enzyme plays an important role in human cell functions. When vitamin D drugs are used in an attempt to arrest certain types of cancer, for example, the tumour responds by making more of this enzyme.

Biochemistry professor Glenville Jones (far right) with his enzyme research team (l to r): research associate David Prosser, current PhD students Martin Kaufmann and Brendan O'Leary, and research technician Valarie Byford.
Credit: Image courtesy of Queen's University

Surprising findings by Queen’s researchers have shed new light on how the “sunshine vitamin” D – increasingly used to treat and prevent cancer and other diseases – is broken down by our bodies.

Related Articles


“The effectiveness of vitamin D therapy is partly dependent on how quickly it will be broken down,” says Biochemistry professor Glenville Jones, an expert in the field of vitamin D metabolism. “By studying the enzyme responsible for breaking down the vitamin, we hope to develop a way to prevent this from happening by blocking that response.”

First observed in Dr. Jones’s lab by undergraduate Biochemistry student Brendan O’Leary, the discovery reveals that changing a single amino acid in the hydroxylase enzyme will cause it to take a completely different pathway. Although scientists have known for 25 years that the enzyme is capable of taking two different pathways, until now they could not explain why this occurs.

Earlier study of the enzyme had shown that its pathway pattern is species specific. Some species, including humans and rats, favour one pathway, while others – most notably the opossum – favour the other pathway.

Using a technique called liquid chromatography mass spectrometry, the researchers studied cells from animals in both categories. They changed the human enzyme in certain key places to see if this would affect its pathway pattern.

Surprisingly, they discovered that altering a single amino acid completely changes the enzyme from a human pattern to an opossum pattern. This change can be flicked back and forth “like a light switch,” says Dr. Jones, adding: “It’s remarkable. In biochemistry you rarely see that kind of predictive work from modeling molecules and enzymes.”

The Queen’s researchers believe the hydroxylase enzyme plays an important role in human cell functions. When vitamin D drugs are used in an attempt to arrest certain types of cancer, for example, the tumour responds by making more of this enzyme. “If we can block the tumour response, we should be able to successfully treat some tumours with vitamin D compounds,” says Dr. Jones, whose research is supported by the Canadian Institutes of Health Research.

Vitamin D deficiency has also been correlated with other diseases, including multiple sclerosis, muscle weakness, and bone-related disorders, he notes.

The team’s findings are published on-line in the journal Proceedings of the National Academy of Sciences (PNAS). Other members include: research associate David Prosser, PhD student Martin Kaufmann, and research technician Valarie Byford.


Story Source:

The above story is based on materials provided by Queen's University. Note: Materials may be edited for content and length.


Cite This Page:

Queen's University. "Enzyme Discovery Sheds Light On Vitamin D." ScienceDaily. ScienceDaily, 25 July 2007. <www.sciencedaily.com/releases/2007/07/070724160205.htm>.
Queen's University. (2007, July 25). Enzyme Discovery Sheds Light On Vitamin D. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2007/07/070724160205.htm
Queen's University. "Enzyme Discovery Sheds Light On Vitamin D." ScienceDaily. www.sciencedaily.com/releases/2007/07/070724160205.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins