Navigation Links
Researchers track antibiotic-resistant strains of Salmonella from farm to fork
Date:8/29/2013

Continuing research on Salmonella may enable researchers to identify and track strains of antibiotic resistant bacteria as they evolve and spread, according to researchers in Penn State's College of Agricultural Sciences.

Tracing the transmission of individual strains from agricultural environments to humans through the food system is difficult because of the rapid evolution of resistance patterns in these bacteria. Resistance patterns change so quickly that, until now, it has been impossible to determine where some highly resistant strains are coming from.

Michael DiMarzio, a doctoral candidate in food science working under the direction of Edward Dudley, associate professor and Casida Development Professor of Food Science, developed a method for identifying and tracking strains of Salmonella enterica serological variant Typhimurium as they evolve and spread.

Every year in the United States, the various strains of Salmonella together are responsible for an estimated 1 million illnesses, 20,000 hospitalizations and 400 deaths at an economic cost exceeding $3 billion. Salmonella Typhimurium accounts for at least 15 percent of clinically reported salmonellosis infections in humans nationally. The number of antibiotic-resistant isolates identified in humans is increasing steadily, suggesting that the spread of antibiotic-resistant strains is a major threat to public health.

"Typhimurium infections have exhibited a gradual decline in susceptibility to traditional antibiotics, a trend that is concerning in light of this pathogen's broad host range and its potential to spread antibiotic resistance determinants to other bacteria," DiMarzio said. "Now more than ever, it is imperative to effectively monitor the transmission of Salmonella Typhimurium throughout the food system to implement effective control measures."

Building on recent research done in Dudley's lab, DiMarzio developed the new approach to identify antibiotic resistant strains of Salmonella Typhimurium focusing on virulence genes and novel regions of the bacteria's DNA known as clustered regularly interspaced short palindromic repeats, or CRISPRs. They report their results in the September issue of Antimicrobial Agents and Chemotherapy.

CRISPRs are present in many foodborne pathogens. The researchers demonstrated that CRISPR sequences can be used to identify populations of Salmonella with common antibiotic-resistance patterns in both animals and humans.

"Specifically, we were able to use CRISPRs to separate isolates by their propensity for resistance to seven common veterinary and human clinical antibiotics," DiMarzio said. "Our research demonstrates that CRISPRs are a novel tool for tracing the transmission of antibiotic-resistant Salmonella Typhimurium from farm to fork."

DiMarzio found that several subtypes of Salmonella Typhimurium showed up repeatedly in the frozen collection of Salmonella samples taken from cows, pigs and chickens in Penn State's Animal Diagnostic Laboratory. In this case, researchers looked at 84 unique Salmonella Typhimurium isolates collected from 2008 to 2011.

"We know those strains are widely disbursed, and the thing they have in common is that they have noticeably higher levels of antibiotic resistance," he said. "So we examined clinical samples of Salmonella taken from humans, and it turned out that we see an overlap -- the ones we see in humans are the ones we see a lot in animals. You would expect that, but it is confirmation that our method works."

DiMarzio noted that the researchers identified subsets of the overall Salmonella bacteria population that seem to be more prone to acquiring antibiotic resistance.

"Our challenge now is to learn what makes those strains different -- why do some strains acquire resistance while others don't, even though both are circulating widely among animal populations?" he said. "We will need to know that to try to control them."


'/>"/>

Contact: A'ndrea Elyse Messer
aem1@psu.edu
814-865-9481
Penn State
Source:Eurekalert

Related biology news :

1. Researchers develop model of near-optimal genetic code
2. Researchers develop novel polymer to help oral medications reach the bloodstream
3. Researchers develop rapid, cost-effective early detection method for organ transplant injury
4. UTHealth, Swedish researchers uncover mystery in blot clotting disorder
5. Researchers develop software tool for cancer genomics
6. Rice, MD Anderson researchers win NIH grant to study protein networks
7. Researchers discover how inhibitory neurons behave during critical periods of learning
8. UCLA researchers invent portable device for common kidney tests
9. Harvard Stem Cell researchers create cells that line blood vessels
10. Researchers figure out why gold nanoparticles can penetrate cell walls
11. Finnish researchers develop quick test kit for detecting phenolic compounds in drinking water
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2016)... and BANGALORE, India , April ... EdgeVerve Systems, a product subsidiary of Infosys (NYSE: ... today announced a global partnership that will provide ... to use mobile banking and payment services.      ... a key innovation area for financial services, but it also ...
(Date:4/19/2016)... UAE, April 20, 2016 The ... as a compact web-based "all-in-one" system solution for all ... fingerprint reader or the door interface with integration authorization ... access control systems. The minimal dimensions of the access ... into the building installations offer considerable freedom of design ...
(Date:4/13/2016)... 13, 2016  IMPOWER physicians supporting Medicaid patients in ... new clinical standard in telehealth thanks to a new ... higi platform, IMPOWER patients can routinely track key health ... mass index, and, when they opt in, share them ... to a local retail location at no cost. By ...
Breaking Biology News(10 mins):
(Date:5/26/2016)... New Jersey and READING, ... Indegene ( http://www.indegene.com ), a leading ... to life science, pharmaceutical and healthcare organisations and ... of innovative scientific support throughout the product lifecycle, ... with the launch of IntraScience.      ...
(Date:5/26/2016)... Despite the volatility that continues to ... Today,s pre-market research on ActiveWallSt.com directs the investor community,s focus ... RDUS ), Cerus Corp. (NASDAQ: CERS ), ... Prime Therapeutics Inc. (NASDAQ: FPRX ). Register with ... http://www.activewallst.com/ On Wednesday, shares in ...
(Date:5/26/2016)... ... 26, 2016 , ... Kinder Scientific (KinderScientific.com), a leading animal ... the Company for the future. Kinder Scientific announces restructured ownership and additional ... appointed Chairman of the Board, Curtis D. Kinghorn has been appointed CEO/President and ...
(Date:5/25/2016)... San Diego, Calif. (PRWEB) , ... May 25, 2016 , ... ... San Diego area and has consistently been rated one of its top attractions. ... over the globe to participate in a unique and intimate team-building experience. , Each ...
Breaking Biology Technology: