Helicobacter Pylori Summary

Article Reference:
Strugatsky, D., McNulty, R., Munson, K., Chen, C.-K., Soltis, S. M., Sachs, G., & Luecke, H. (2013). Structure of the proton-gated urea channel from the gastric pathogen Helicobacter pylori. Nature, 493(7431), 255+.

Purpose:
The purpose of this article is to figure out the structure of the proton-gated urea channel from the gastric pathogen Helicobacter pylori by using multi-wavelength anomalous dispersion. By figuring out this structure, the treatment of H. pylori can be more beneficial.

Unit Topic:
The unit of study that best relates to this article is unit four. This unit best relates to the article because in the article, the HpUrel channel would open at acidic pH; thus, allowing the flow of urea to cytoplasmic urease.

In unit four, Friedrich Wohler in 1828 accidentally synthesized urea. Another unit of study that relates to this article is unit 3. This unit relates to the article because in the article, pH is a huge determining factor in whether or not the HpUrel channel would open or remain closed. The article also states that urease activity buffers the periplasm to a pH of 6.1. This is really important for the survival of Helicobacter pylori. In unit 3, we talked about pH and the importance of buffers.

Summary:
Helicobacter Pylori is an infection that causes gastric ulcers, an increase of gastric adenocarcinoma, and gastritis.

Helicobacter Pylori is something that much of the human population is infected with. The treatment of this infection is becoming less successful because of the increase in antibiotic resistance. This suggests that a more targeted approach would be advantageous to exterminate this organism. In order to find a treatment that will be effective, the unobserved structure of HpUrel must be determined.
The presence of HpUrel, which is a proton gated inner membrane urea channel, is essential for survival in the acidic mammalian stomach. The pH has a major role in determining whether or not the channel closes or opens. When the pH is neutral, the channel is closed. When the pH is acidic, the channel opens; thus, allowing the access of urea to cytoplasmic urease. The channel fully opens at a pH of about 5.0, which enables the entry of urea into the bacterium. Even in the acidic environment of the stomach, urease buffers the periplasm to a pH of about 6.1, and neutralizes the incoming protons. This is essential for the survival of Helicobacter

Pylori.
Through the use of multi-wavelength anomalous dispersion, the structure of HpUrel was determined.

HpUrel is reported to measure 45 A in height and 95 A in diameter. The HpUrel is also reported to have the structure of six protomers put together in a hexametric ring, which surrounds a bilayer of lipids. This native hexametric structure for HpUrel was confirmed with the use of blue native gel electrophoresis. In the periplasmic leaflet there are six lipid tails. In the cytoplasmic leaflet, there are eighteen lipid tails. Each protomer surrounds a channel, which is formed by six trans-membrane helices. This bundle of helices has a fold, which is seen as a two-helix hairpin pattern that is repeated three times around the center axis of the channel. With these findings, effective treatments for Helicobacter Pylori, and possibly even a cure to this infection can now have a greater chance of being found.

New Vocabulary:
With reading such a difficult article, I learned a lot of new vocabulary. I learned that motif means a decorative design or pattern. Her dress featured a checkered motif. Another word I learned was urease, which is an enzyme that hydrolyzes urea into ammonium carbonate. The enzyme urease catalyzes the reaction of urea.

Personal

Comments:
Originally when I found this article, I had no idea how I was going to be able to read it. It was extremely advanced and well beyond my ability to understand. Instead of giving up and trying to find a different article; however, the stubborn side of me decided to suck it up and learn how to understand the article. It took me a couple of days of research to understand it, and even after all my best efforts there’s still some parts I do not fully understand. This article was a challenge, but overall I’m generally really proud and pleased with myself that I stuck with it.
I felt that this article was really important because now that the structure of Helicobacter pylori is known, treatments can be more effective. Sometime in the future we might be able to even fully cure this infection.
After reading this article, there are still many questions that I would have to research. I would like to know why some people suffer from this infection and why some people do not. I would also like to know what kind of treatments were previously used and worked. Likewise, I would like to know what kind of treatments that were previously used that did not work, and why such treatments did not work. Most importantly, I would like to know what kind of treatments doctors are now going to try to use because they know the structure of Helicobacter pylori.