Navigation Links
NIH scientists link quickly spreading gene to Asian MRSA epidemic

National Institutes of Health (NIH) scientists and their colleagues in China have described a rapidly emerging Staphylococcus aureus gene, called sasX, which plays a pivotal role in establishing methicillin-resistant S. aureus (MRSA) epidemics in most of Asia. Senior author Michael Otto, Ph.D., of NIH's National Institute of Allergy and Infectious Diseases, says these findings illustrate at the molecular level how MRSA epidemics may emerge and spread. Moreover, their study identifies a potential target for novel therapeutics.

MRSA is a leading cause of severe infections that occur predominantly in hospitals. MRSA epidemics happen in waves, with old clones of MRSA bacteria disappearing and new clones emerging, a process whose molecular underpinnings are not fully understood.

Previous data indicated that the sasX gene is extremely rare. Therefore, the researchers were surprised when they analyzed 807 patient samples of invasive S. aureus taken over the past decade from three Chinese hospitals. Their data showed that sasX is more prevalent in MRSA strains from China than previously thought, and the gene's frequency is increasing significantly: From 2003 to 2011, the percentage of MRSA samples containing sasX almost doubled, from 21 to 39 percent.

This finding suggests that the sasX gene is involved in molecular processes that help MRSA spread and cause disease. The researchers determined in laboratory and mouse studies that sasX helps bacteria to colonize in the nose, cause skin abscesses and lung disease, and evade human immune defenses. Further, the scientists say their work provides additional evidence for a long-held theory that the emergence of new clones of highly virulent MRSA bacteria occurs through horizontal gene transfer, the exchange of DNA between different strains. Notably, the sasX gene is embedded in a so-called mobile genetic element, a DNA segment that can transfer easily between strains.

Most sasX-positive samples found in the study were from the ST239 group, the predominant MRSA lineage in China and large parts of Asia. However, because the scientists have already observed the transfer of sasX to MRSA clones other than those belonging to the ST239 group, Dr. Otto and his team predict that the frequency of sasX will increase internationally. They plan to both monitor its spread and work to develop therapeutics to prevent MRSA strains expressing sasX from colonizing and infecting people.

Min Li, Ph.D., associate professor at Fudan University in Shanghai, a former postdoctoral fellow in Dr. Otto's laboratory, designed the study. Other collaborators are from the University of California, San Francisco.


Contact: Ken Pekoc
NIH/National Institute of Allergy and Infectious Diseases

Related medicine news :

1. Warwick scientists uncover how checkpoint proteins bind chromosomes
2. Scientists rewrite rulebook on breast cancer in landmark global study
3. Scientists tailor cell surface targeting system to hit organelle ZIP codes
4. Scientists identify major source of cells defense against oxidative stress
5. Scientists uncover multiple faces of deadly breast cancer
6. Scientists solving the mystery of human consciousness
7. A*STAR scientists discover special class of natural fats stimulates immune cells to fight diseases
8. Hutchinson Center and TGen scientists discover potential break through in pancreatic cancer
9. Scientists study link between amyloid beta peptide levels and Alzheimers disease
10. Scientists measure how energy is spent in martial arts
11. Scientists link 2 cancer-promoting pathways in esophageal cancer
Post Your Comments:
(Date:10/13/2017)... ... October 13, 2017 , ... The American Board of Family Medicine's ... President and Chief Executive Officer, succeeding Dr. James C. Puffer upon his retirement. Dr. ... 2018 until Dr. Puffer’s retirement at the end of 2018. Upon assuming the role ...
(Date:10/13/2017)... ... ... Apple Rehab Shelton Lakes , which specializes in the delivery of sub-acute ... of a disaster drill on October 3rd. , Apple Rehab participated with the Shelton ... well as the Connecticut Long Term Care Mutual Aid Plan (LTC-MAP). The LTC-MAP ...
(Date:10/13/2017)... Texas (PRWEB) , ... October 13, 2017 , ... Yisrayl ... this week that explains one of the most popular and least understood books in ... like cryptic and puzzling descriptions that have baffled scholars for centuries. Many have tossed ...
(Date:10/12/2017)... ... October 12, 2017 , ... First ... compliance program management, will showcase a range of technology and learning solutions at ... (NCAL) Convention and Expo to be held October 14–18, 2017 at the Mandalay ...
(Date:10/12/2017)... ... , ... The American College of Medical Informatics (ACMI) will present the 2017 ... Session of AMIA’s Annual Symposium in Washington, D.C. AMIA’s Annual Symposium is ... pioneer in the field of medical informatics, this prestigious award is presented to an ...
Breaking Medicine News(10 mins):
(Date:9/27/2017)... Israel and NEW YORK , Sept. 27, ... with mobile health and big data solutions, today announced that its MyDario ... Please check your local TV listings for when The Dr. Oz Show ... ... season this month. ...
(Date:9/23/2017)... , Sept. 22, 2017 Janssen Biotech, ... complete response letter from the U.S. Food and Drug ... approval of sirukumab for the treatment of moderately to ... indicates additional clinical data are needed to further evaluate ... to severely active RA. ...
(Date:9/19/2017)... medical device company developing a non-invasive, robotically assisted, platform therapy that uses pulsed sound energy ... ... Jim Bertolina, PhD ... Tom Tefft ... executive Josh Stopek , PhD, who has led R&D and business development teams at ...
Breaking Medicine Technology: