Navigation Links
Supersized 'island' of resistance genes discovered in an infectious bacterium

Researchers have discovered a cluster of 45 genes coding for antibacterial drug resistance in the bacterium, Acinetobacter baumannii, a major cause of hospital-acquired infections worldwide. The study was reported in the open-access journal PLoS Genetics.

"We expected to find resistance genes," said lead author, Pierre-Edouard Fournier, researcher at the Structural and Genomic Information Laboratory at France's National Center for Scientific Research (CNRS). "But the grouping of most of these genes within a single genomic island was totally unexpected." The resistance island--a group of resistance genes clustered close together on a chromosome--is the largest discovered to date.

The research team also discovered new resistance genes. "We were surprised to discover 19 new resistance genes that escaped the scrutiny of the large number of laboratories already working on multi-drug resistant A. baumannii throughout the world. This is a demonstration of the efficiency of the whole genome approach in characterizing new pathogens," said Jean-Michel Claverie, senior author of the report and Director of the Structural and Genomic Information Laboratory at CNRS.

This bacterium acquires resistance genes quickly--just thirty years ago it was completely susceptible to antibiotics and now it is resistant to a wide-range of antibiotics.

"A. baumannii is exceptionally prone to pick up foreign DNA from other bacteria," Claverie said. The study traced the origin of many resistance genes to other bacteria, including Salmonella, indicating frequent genetic swapping between bacteria.

Resistance genes are usually located on small auxiliary circles of DNA called plasmids that can be exchanged with other individuals. But in A. baumannii, resistance genes were incorporated into the main chromosome, not the plasmids, according to the study.

"It is like the A. baumannii genome is 'anticipating' any antibacterial challenge by setting up some kind of easily accessible 'shelves' to store the antibacterial resistances genes as they become needed and are available in the environment," Claverie said.

The research team compared the entire genomes of two A. baumannii strains, one completely susceptible to antibiotics and one highly resistant.

"This is the first study of its kind to study the resistance mechanisms of a bacterial strain by whole genome sequencing," said Fournier. "Our strategy of sequencing the whole genome of a bacterial strain with specific features is valuable and fast."

Resistant A. baumannii has become a major public health concern worldwide. Recently, a high incidence of resistant A. baumannii was reported in US Army service members injured in Afghanistan and Iraq. In France, the resistant strain is widespread in 54 healthcare facilities, where 26% of infected patients die.

"Less than 2 years after the start of the French epidemic episode, we found the complete genome ID of the microbe involved and developed a better understanding of what to expect for the future, in terms of new antibiotic resistance," Claverie said. "This work will guide a future international effort on identifying all major A. baumannii resistant strains throughout the world, and help follow the emergence of new strains and understand their mode of evolution."


'"/>

Source:Public Library of Science


Related biology news :

1. Plant defenses prompt bacterial countermeasure in the form of island DNA excision
2. Study identifies predictors of HIV drug resistance in patients beginning triple therapy
3. Researchers make gains in understanding antibiotic resistance
4. MUHC scientists describe genetic resistance to rampant virus
5. New polysaccharide may help combat multidrug resistance in cancer
6. New book explains antibiotic resistance for a broad audience
7. Insects develop resistance to engineered crops
8. Retroviral resistance gene found
9. Drug resistance testing in treatment-naive HIV patients is cost-effective
10. Researchers use RNAi libraries to identify regulators of apoptosis and chemoresistance
11. Gaining ground in the race against antibiotic resistance
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/2/2016)... , June 2, 2016 The Department ... has awarded the 44 million US Dollar project, for the ... Vehicle Plates including Personalization, Enrolment, and IT Infrastructure , ... in the production and implementation of Identity Management Solutions. Numerous ... however Decatur was selected for the ...
(Date:5/20/2016)... May 20, 2016  VoiceIt is excited to ... VoicePass. By working together, VoiceIt and ... VoiceIt and VoicePass take slightly different approaches to ... both security and usability. ... this new partnership. "This marketing and ...
(Date:4/28/2016)... and BANGALORE, India , April 28, 2016 ... a product subsidiary of Infosys (NYSE: INFY ), ... a global partnership that will provide end customers ... mobile banking and payment services.      (Logo: ... innovation area for financial services, but it also plays a ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... ... and technical consulting, provides a free webinar on Performing Quality Investigations: ... 2016 at 12pm CT at no charge. , Incomplete investigations are still a ...
(Date:6/23/2016)... June 22, 2016  Amgen (NASDAQ: AMGN ... QB3@953 life sciences incubator to accelerate the ... shared laboratory space at QB3@953 was created to help ... obstacle for many early stage organizations - access to ... sponsorship, Amgen launched two "Amgen Golden Ticket" awards, providing ...
(Date:6/22/2016)... DIEGO , June 22, 2016 ... that will allow them to produce up to ... from one lot within one week. These high-quality, ... time laboriously preparing cells and spend more time ... possible through a proprietary, high-volume manufacturing process that ...
(Date:6/22/2016)...  According to Kalorama Information, the dominant trends ... include significant efforts in automation as well as ... affordable sequencers, say the healthcare market research firm, ... sample prep materials.  The healthcare market research company,s ... Next Generation Sequencing (NGS) , highlights major trends ...
Breaking Biology Technology: