First large-scale analysis completed of intra-species genetic variation in gut’s resident organisms
HSNewsBeat | Updated 9:00 AM, 01.29.2015
|Posted in: Research
From the 29 January 2015 University of Washington press release
First large-scale analysis completed of intra-species genetic variation in gut’s resident organisms
HSNewsBeat | Updated 9:00 AM, 01.29.2015
|Posted in: Research
Designer viruses could be the new antibiotics | Ars Technica.by Oct 16 2014, 11:30am EDT
From the news article
Bacterial infections remain a major threat to human and animal health. Worse still, the catalog of useful antibiotics is shrinking as pathogens build up resistance to these drugs. There are few promising new drugs in the pipeline, but they may not prove to be enough. Multi-resistant organisms—also called “superbugs”—are on the rise, and many predict a gloomy future if nothing is done to fight back.
The answer, some believe, may lie in using engineered bacteriophages, a type of virus that infects bacteria. Two recent studies, both published in the journal Nature Biotechnology, show a promising alternative to small-molecule drugs that are the mainstay of antibacterial treatments today.
From basic to synthetic biology
Nearly every living organism seems to have evolved simple mechanisms to protect itself from harmful pathogens. These innate immune systems can be a passive barrier, blocking anything above a certain size, or an active response that recognizes and destroys foreign molecules such as proteins and DNA.
An important component of the bacterial immune system is composed of a family of proteins that are tasked specifically with breaking down foreign DNA. Each bug produces a set of these proteins that chew the genetic material of viruses and other micro-organism into pieces while leaving the bacterial genome intact.
In vertebrates, a more advanced system—called the adaptive immune system—creates a molecular memory of previous attacks and prepares the organism for the next wave of infection. This is the principle on which vaccines are built. Upon introduction of harmless pathogen fragments, the adaptive immunity will train specialist killer cells that later allow a faster and more specific response if the virulent agent is encountered again.
Crisp news
Until recently, people thought bacteria were too simple to possess any sort of adaptive immunity. But in 2007, a group of scientists from the dairy industry showed that bacteria commonly used for the production of cheese and yogurts could be “vaccinated” by exposure to a virus. Two years earlier, others noticed similarities between repetitive sections in bacterial genomes and the DNA of viruses. These repetitive sequences—called CRISPR for “clustered regularly interspaced short palindromic repeats”—had been known for 20 years, but no one could ever explain their function.
Do our medicines boost pathogens?
From the 21 December 2011 Science News Today article
Scientists of the Institute of Tropical Medicine (ITG) discovered a parasite that not only had developed resistance against a common medicine, but at the same time had become better in withstanding the human immune system. With some exaggeration: medical practice helped in developing a superbug. For it appears the battle against the drug also armed the bug better against its host.
“To our knowledge it is the first time such a doubly armed organism appears in nature,” says researcher Manu Vanaerschot, who obtained a PhD for his detective work at ITG and Antwerp University. “It certainly makes you think.”…