Researchers Find Compound Effective In Destroying Antibiotic-Resistant Biofilms

[OKIsItJustMe]

http://news.ncsu.edu/releases/melander/

Researchers Find Compound Effective In Destroying Antibiotic-Resistant Biofilms

For Immediate Release

Tracey Peake | News Services | 919.515.6142

Release Date: April 8, 2010

Researchers at North Carolina State University have found a chemical compound that, when used in conjunction with conventional antibiotics, is effective in destroying biofilms produced by antibiotic-resistant strains of bacteria such as the Staphylococcus strain MRSA and Acinetobacter. The compound also re-sentsitizes those bacteria to antibiotics.

Infections from antibiotic-resistant bacteria such as MRSA are especially difficult to get rid of because the bacteria can attach to surfaces and then create biofilms, sticky layers of cells that act as a shield and prevent antibiotics from destroying the bacteria underneath. While a limited number of existing antibiotics may destroy part of the biofilm, enough bacteria survive to create a recurring infection as soon as antibiotic therapy stops, and over time the surviving bacteria build resistance to that antibiotic.

NC State chemist Dr. Christian Melander had already shown that combining a compound made from a class of molecules known as 2-aminoimidazoles with antibiotics was effective in dispersing the biofilms created by certain bacterial strains. The next step was to see if this combination could remove resistant bacteria from surfaces.

“The problem with biofilms is that even if you treat with effective antibiotics, they never succeed in completely dispersing the biofilm and killing the bacteria on the surface they’ve stuck to,” Melander says. “This is especially exacerbated when the bacteria are antibiotic-resistant. Basically, if you are trying to treat a multi-drug resistant bacterial infection, you need to worry about both the bacteria forming a biofilm and disarming their antibiotic resistance genes.”

Melander and his team, in collaboration with NC State biochemist John Cavanagh, found that pre-treating the bacteria with their compound and then introducing the antibiotic penicillin one hour later increased the penicillin’s effectiveness 128-fold, even when the bacteria was penicillin resistant. The antibiotics also provided a 1,000-fold enhancement to the ability of the 2-aminoimidazole to disperse biofilms.

The researchers’ results were published online March 8 in the journal Antimicrobial Agents and Chemotherapy.

“We had two goals in mind – to overcome antibiotic resistance and to disperse biofilms,” Melander says. “This compound cooperates with conventional antibiotics, overcoming an infectious threat that would otherwise persist if treated with either agent individually.”

The Department of Chemistry is part of NC State’s College of Physical and Mathematical Sciences, and the Department of Biochemistry is a part of the College of Agriculture and Life Sciences.

-peake-Note to editors: An abstract of the paper follows.

“Synergistic Effects Between Conventional Antibiotics and 2-Aminoimidazole-Derived Antibiofilm Agents”

Authors: Christian Melander, Steven A. Rogers, Robert W. Huigens III and John Cavanagh, NC State University

Published: Online in March 8 edition of Antimicrobial Agents and Chemotherapy

Abstract: 2-Aminoimidazoles are an emerging class of small molecules that possess the ability to inhibit and disperse biofilms across bacterial order, class and phylum. Herein, we report the synergistic effect between a 2-aminoimidazole/triazole conjugate and antibiotics toward dispersing pre-established biofilms, cumulating with a three orders of magnitude increase of biofilm dispersion towards Staphylococcus aureus biofilms. Furthermore, we document that the 2-Aminoimidazole/triazole conjugate will also resensitize multi-drug resistant strains of bacteria to the effects of conventional antibiotics, including MRSA and multi-drug resistant Acinetobacter baumannii.

[Dogmudgeon]

1. Woo hoo!

:woohoo:

I've been in de facto quarantine since Xmas -- I have resistant strains of both staphylococci and streptococci, and have been off-limits to my relatives under age 12. Which also means their parents.

And the ear infections and cellulitis aren't such a vacation, either. (Right now, my immune system has gotten the better of the struggle. ¡Viva la Lucha!)

The breakdown of human ecology sure does suck. I'm happy for this breakthrough, but we need some ecological solutions to prevent these custom-mutated pathogens from evolving in the first place. Same deal with food -- reform (get rid of) industrial farming practices and replenish the soil, THEN think about genetic modification.

One crisis at a time ...

--d!

[OKIsItJustMe]

3. It will be a while before this can help you I fear

In the meantime encourage all of your visitors to wash their hands diligently.

http://www.eurekalert.org/pub_releases/2009-03/sfgm-hmi032709.php

31 March 2009

Handwashing more important than isolation in controlling MRSA superbug infection

Regular handwashing by hospital staff and visitors did more to prevent the spread of the MRSA superbug than isolating infected patients.

At the Society for General Microbiology meeting in Harrogate today (Tuesday 31 March), Dr Peter Wilson from University College Hospital, London, reported on a year-long study in two hospital intensive care units. In the middle six months of the year patients with MRSA were not moved to single rooms or nursed in separate MRSA bays. The rates of cross infection with MRSA were compared to the periods when patients were moved. Patients were tested for MRSA weekly and hand hygiene by staff and visitors was audited and encouraged. There was no evidence of increased transmission of infection when patients were not moved.

Moving seriously-ill patients when they are identified as having MRSA can be hazardous and it involves ward staff in extra hygiene measures.

MRSA are Staphylococcus aureus bacteria that are resistant to the meticillin class of antibiotics. Many people carry these bacteria and it is generally not harmful if they are healthy. MRSA can cause serious illness in patients with weak or damaged immune systems and the elderly and it is widespread in hospitals. Treatment options are limited and it is vitally important to develop strategies to stop the spread of MRSA in healthcare environments.

'If a patient carrying MRSA is critically ill, moving them to a single room is less of a priority than clinical care,' said Dr Wilson. 'If the criteria are strictly applied, compliance with hand hygiene practices on intensive care units is less than on a general ward because of the very high number of contacts per hour. Another study is needed in a general ward where a high level of compliance with hand hygiene is easier to achieve.'

...

[damntexdem]

2. Wonderful news!

I sent the URL to my state public health affiliate.