Scientists have announced that hospital 'superbugs', bacteria resistant to antibiotics, have been dealt a blow by the decoding of the genomes of two of the most feared of the bugs.
Japanese researchers from Juntendo University in Tokyo have decoded the DNA sequence of two antibiotic-resistant strains of the bacteria staphylococcus aureus. One of these strains, methicillin-resistant Staphylococcus aureus (MRSA), infects patients who have had operations and has become endemic in hospitals. The other, vancomycin-resistant Staphylococcus aureus (VRSA) has developed a resistance to what is known as the 'last resort' antibiotic vancomycin, which was, until recently, an effective treatment against MRSA.
It is hoped that the complete DNA sequences of the two bugs will help show why they can cause such devastation and lead to the design of therapies or vaccines. The scientists have discovered 70 new genes which could affect the virulence of the bugs and which could be targets for new drugs.
The research also shows that the genes of Staphylococcus aureus have been partly acquired from other organisms, ranging from bacteria to human beings. It is this characteristic, combined with the repeated duplication of harmful genes, that gives the bug its 'super' power. It has also been discovered that the antibiotic-resistant genes exist along mobile lengths of DNA known as plasmids. These have the ability to spread across strains of staphylococcus aureus, as well as across species.
Sources and References
-
Breakthrough in 'superbug' battle
-
War on superbugs enlists genetic codes
-
Genetic 'weapon' breakthrough in superbug fight
-
Scientists crack genetic code of staph superbug
Related Articles
Genome researchers track and stop spread of killer bug
An outbreak of a drug-resistant bacterial bug, which killed six people and infected 11 more, was stopped partially thanks to genome sequencing, a paper in Science Translational Medicine reports...
MRSA spread from city to regional hospitals tracked with genetic tags
The emergence and spread of MRSA in the UK has been tracked thanks to genetic analysis of samples taken from infected patients over a 53-year period. The study, published in the journal PNAS, suggests that hospitals in large cities act as breeding grounds for new, increasingly resistant MRSA variants...
MRSA superbug evades immune defences with a jumping gene
A gene identified in MRSA may contribute to the spread and virulence of the superbug. The gene - sasX - is located in a segment of DNA called a mobile genetic element and is capable of jumping from one bacterium to another...
Black Death DNA puzzle no longer plagues scientists
DNA extracted from the teeth of plague victims buried in London over 660 years ago has been used to reconstruct the genome of the bacteria that led to the Black Death. The study, carried out by a team of scientists from Canada and Germany, showed that the genetic make-up of this medieval bacteria has remained remarkably unchanged compared to modern day strains...
New MRSA strain not picked up by current genetic tests
A group of British and Danish scientists has identified a new strain of methicillin-resistant Staphylococcus aureus (MRSA), which has been found in cows and their milk. The new strain is also known to have infected 27 people in the UK and 24 in Denmark...
Leave a Reply
You must be logged in to post a comment.