About Careers Internship MedBlogs Contact us
Medindia LOGIN REGISTER
Advertisement

Researchers Zero in on Antibiotic Resistance Enzyme

by Kathy Jones on April 8, 2014 at 10:43 PM
Font : A-A+

 Researchers Zero in on Antibiotic Resistance Enzyme

New biochemistry research indicates that resistance to an entire class of antibiotics called aminoglycosides has the potential to spread to many types of bacteria.

A mobile gene called NpmA was discovered in E. coli bacteria isolated from a Japanese patient several years ago. Global spread of NpmA and related antibiotic resistance enzymes could disable an entire class of tools doctors use to fight serious or life-threatening infections.

Advertisement

Using X-ray crystallography, researchers at Emory University School of Medicine made an atomic-scale snapshot of how the enzyme encoded by NpmA interacts with part of the ribosome, protein factories essential for all cells to function. NpmA imparts a tiny chemical change that makes the ribosome, and the bacteria, resistant to the drugs' effects.

The results, published in PNAS Early Edition, provide clues to the threat NpmA poses, but also reveal potential targets to develop drugs that could overcome resistance from this group of enzymes.
Advertisement

First author of the paper is postdoctoral fellow Jack Dunkle, PhD. Co-senior authors are assistant professor of biochemistry Christine Dunham, PhD and associate professor of biochemistry Graeme Conn, PhD.

Doctors generally use aminoglycoside antibiotics only for serious infections, because they can be toxic to the kidney and inner ear. But the growing problem of resistance to other types of antibiotics has sparked renewed interest in aminoglycosides' clinical use.

Examples of aminoglycosides include: streptomycin (the first antibiotic remedy for tuberculosis), kanamycin, tobramycin (often used in cystic fibrosis), gentamicin and neomycin.

Aminoglycosides bind to ribosomes, interfering with protein production in bacteria. Most mobile genes that confer aminoglycoside resistance chemically alter the antibiotics, and are active against only a few antibiotics. Instead, the NpmA-encoded enzyme modifies the ribosome so that aminoglycoside antibiotics don't interfere with it anymore. That's why it's more dangerous.

Another feature of NpmA that makes it dangerous is that it recognizes structural features that are common to all bacterial ribosomes. The information the Emory team obtained suggests that NpmA, found in E. coli, could easily work in other types of bacteria.

The structures of ribosome alone and the NpmA enzyme alone were already available; the Emory team was able to capture the two together in a "pre-catalytic state."

Aminoglycosides are naturally produced by certain types of soil bacteria against other bacteria, and the producer bacteria have to make a resistance enzyme to prevent self-poisoning. Scientists hypothesize that the genes that encode this type of resistance enzymes in pathogenic bacteria were originally acquired from an aminoglycoside producer, Conn says.



Source: Eurekalert
Advertisement

Advertisement
News A-Z
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
What's New on Medindia
Monkeypox Outbreak: What it is, How Does it Spread & the Prevention
Seasonal Allergy Medications
How to Choose the Best Eczema-Friendly Moisturizer for Children?
View all
Recommended Reading
News Archive
Date
Category
Advertisement
News Category

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
MRSA - The Super Bug Drug Resistance - Antibiotic Resistance Food Preservatives - How Safe Are They? Antibiotics Eye Infections Natural Antibiotics to Fight Bacterial Infections Antibiotic Resistance - An Emerging Global Crisis 

Most Popular on Medindia

Drug Interaction Checker Blood Pressure Calculator Find a Hospital Find a Doctor Iron Intake Calculator Nutam (400mg) (Piracetam) Sinopril (2mg) (Lacidipine) Loram (2 mg) (Lorazepam) Calculate Ideal Weight for Infants Sanatogen

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2022

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use