Navigation Links
Targeted antibacterial proteins may offer antibiotic alternative
Date:11/20/2011

SOUTH SAN FRANCISCO, CA -- A novel antibacterial protein targeted against E. coli O157:H7 may offer a way to prevent or treat serious food-borne bacterial infections, as demonstrated in a study published in the December issue of Antimicrobial Agents and Chemotherapy. Results in an animal model of E. coli infection showed that the orally administered protein, developed by AvidBiotics, Inc., could prevent or treat E. coli O157:H7-induced diarrhea and intestinal inflammation when administered either on a preventative basis or after the onset of diarrhea. Moreover, animals treated with the protein also carried and shed fewer of the E. coli O157:H7 bacteria in their feces.

"E. coli O157:H7 contamination of foods like ground meats or produce is a well-publicized public health problem, with life-threatening infection outbreaks reported around the world in recent years," said Dean Scholl, Ph.D., lead author of the publication. "Antibiotics are contraindicated for patients infected with enterohemorrhagic E. coli (EHEC) strains like O157:H7, because many of those drugs induce the bacteria to produce and release harmful toxins. Anti-diarrheal medications also do not benefit infected patients, as they cause the bacteria to be retained in the intestines, leading to greater toxin exposure. Thus the successful development of treatments that can prevent infection or limit symptoms and disease duration and the possible further spread of harmful bacteria without increasing toxin release could benefit both individual patients and affected communities."

The study published by Dr. Scholl and his collaborators at AvidBiotics and Brigham and Women's Hospital/Harvard Medical School assessed AvidBiotics' anti-E. coli O157 protein, termed an Avidocin protein, in a rabbit model of infection and reported that:

  • The Avidocin protein remained active within the treated animals' intestinal tract for at least 24 hours post administration.
  • When given shortly after the animals were infected with E. coli O157:H7 but before they developed active disease, the Avidocin protein inhibited bacterial colonization and/or the symptoms of infection. Animals that received the highest dose of protein studied did not develop diarrhea at any time during the experiment. In contrast, animals given buffer alone developed typical diarrhea within 1-2 days after infection, which worsened by the 3rd day of the study.
  • Analyses of colon tissue showed less severe intestinal inflammation in Avidocin protein-treated animals compared to controls. Avidocin protein administration also greatly reduced the number of E. coli O157:H7 recovered from the intestine and the stool of treated animals.
  • When the anti-E. coli O157:H7 Avidocin protein was administered to infected animals already exhibiting disease symptoms, the existing diarrhea began to resolve in treated animals compared to animals treated with placebo. This reduction in diarrhea persisted until the experiment was terminated, 9 days post infection, at which time the feces of the treated animals appeared closer to feces from uninfected animals than the still largely liquid stool of the control animals. Thus, even after the onset of diarrhea in E. coli O157:H7-infected animals, administration of the anti-E. coli O157:H7 Avidocin protein could still mitigate the effects of infection.

"These findings suggest that an Avidocin protein targeted against E. coli O157:H7 offers promise for both the prevention and treatment of infection by this important enteric pathogen," concluded Dr. Scholl. "Moreover, this agent provides several significant advantages over conventional antibiotics, including a lack of drug-induced shiga toxin production and unintended collateral damage to normal intestinal bacterial populations. Additionally those rare variants of E. coli O157:H7 that emerge resistant to the anti-E. coli O157:H7 Avidocin protein are likely to have compromised virulence, or disease-causing properties."

About the Avidocin Protein Platform

AvidBiotics genetically engineers Avidocin proteins from R-type pyocins, antibacterial proteins produced by some Pseudomonas aeruginosa strains. These proteins specifically kill bacteria by binding to the bacterial cell and punching a hole in the cell envelope, causing membrane depolarization and ultimately cell death. AvidBiotics has previously demonstrated that Avidocin proteins can be engineered to recognize and kill in a highly targeted and specific manner a variety of bacteria, including E. coli, Salmonella, Shigella, Clostridium difficile, and Yersinia pestis (the bacterium that causes plague), thus serving as a platform for the production of numerous highly specific antibacterial agents.

AvidBiotics is also currently developing Avidocin proteins against Acinetobacter, a bacterium associated with serious, often broadly antibiotic-resistant infections in Intensive Care Units and those incurred by U.S. military deployed in Iraq and Afghanistan. In addition to the human health care uses of the Avidocin technology, AvidBiotics is collaborating with food safety and hygiene company EcoLab to develop antibacterial proteins for use against E. coli O157:H7 in meat processing.


'/>"/>
Contact: Joan Kureczka
Joan@kureczka-martin.com
415-821-2413
Kureczka/Martin Associates
Source:Eurekalert

Related biology news :

1. On the trail of a targeted therapy for blood cancers
2. Cellular discovery may lead to targeted treatment for rare form of anemia
3. Molecular fingerprints point the way to earlier cancer diagnosis and more targeted treatment
4. Targeted drug therapy prevents exercise-induced arrhythmias
5. Breakthrough in radiotherapy promises targeted cancer treatment
6. Genetic finding could lead to targeted therapy for neuroblastoma
7. New subtype of breast cancer responds to targeted drug
8. Caltech-led team provides proof in humans of RNA interference using targeted nanoparticles
9. UC to test targeted treatment for prostate cancer
10. New mechanisms of tumor resistance to targeted therapy in lung cancer are discovered
11. New targeted therapy adds benefit to erlotinib in some patients with advanced lung cancer
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/14/2016)... 2016 NXTD ) ("NXT-ID" or the ... announces the airing of a new series of commercials on ... March 21 st .  The commercials will air on Bloomberg ... on the Street show. --> NXTD ) ("NXT-ID" ... commerce market, announces the airing of a new series of ...
(Date:3/11/2016)... http://www.apimages.com ) - --> http://www.apimages.com ... at AP Images ( http://www.apimages.com ) - Germany ... produce the new refugee identity cards. DERMALOG will be unveiling this ... Hanover next week.   --> ... to produce the new refugee identity cards. DERMALOG will be unveiling ...
(Date:3/10/2016)... , March 10, 2016 ... market research report "Identity and Access Management Market by ... Compliance, and Governance), by Organization Size, by Deployment, by ... published by MarketsandMarkets, The market is estimated to grow ... Billion by 2020, at a Compound Annual Growth Rate ...
Breaking Biology News(10 mins):
(Date:5/4/2016)... York , May 4, 2016 ... Transparency Market Research "Metabolomics Market - Global Industry Analysis, ... the metabolomics market is anticipated to expand at a ... USD 2,494.8 million by 2024. Metabolomics is ... metabolites, within cells, biofluids, tissues or organisms. Together, these ...
(Date:5/3/2016)... Francisco, CA (PRWEB) , ... May 03, 2016 ... ... Morf Playbook™ enterprise talent development, skill-building and compliance training platform on mobile ... training course: Overview of Regulatory Requirements for Medical Devices. The course is ...
(Date:5/3/2016)... ... May 03, 2016 , ... Kerafast Inc., developers ... from laboratories across the globe, today announced the availability of a Zika virus ... research toward treatment and prevention measures for the Zika virus, the virus’s geographical ...
(Date:5/3/2016)... ... 2016 , ... According to world renowned prostate cancer surgeon, Dr. David ... had two main treatment options: surgery or radiation. Based on a patient’s goals, disease ... has enabled doctors to administer higher doses of radiation to prostate cancer ...
Breaking Biology Technology: