|at 4/16/2018 04:08:00 PM||DISEASES|
Origin of teixobactinFirst of all, teixobactin is a peptide, and it comes from a soil bacterium that was difficult to culture. But a new culture method made it possible to isolate teixobactin. Subsequently the biochemists were able to create the identical antibiotic synthetically.
This moment likely is as important as the original discovery of penicillin. Experiments in the Petri dish and in mice show that teixobactin is a broad spectrum antibiotic, has no toxicity and treats all of the problem bugs that are associated with drug resistance. To the clinician it is a dream come true. For decades they hoped for an effective treatment for drug resistant bacteria. And now this seems to materialize. In the US there are 2 million drug resistant infections every year. More than 23,000 patients die from them every year.
Six problem bugs that are drug resistantThere are currently 6 problem bugs that have developed resistance. 1 in 4 nursing home patients may have one of these resistant bugs: carbapenem-resistant Enterobacteriaceae, methicillin-resistant Staphylococcus aureus (MRSA), ESBL-producing Enterobacteriaceae, vancomycin-resistant Enterococcus (VRE), multidrug-resistant Pseudomonas aeruginosa and multidrug-resistant Acinetobacter.
3 years ago a research team showed that teixobactin killed MRSA and VRE. The underlying publication by Ishwar Singh and colleagues described how cyclic peptides their research team has successfully synthesized teixobactin analogues. He said that these findings may “lead to the first new class of antibiotic drug in 30 years”.
Mouse experiments using teixobactin analoguesThe next level of evidence came from mouse experiments. Ten analogues of teixobactin were tested on mice that had infections due to drug resistant bacteria.
One team working at the Singapore Eye Research Institute could show that mice that had Staphylococcus aureus keratitis (infection of the cornea with bacteria) achieved a cure of this infection with synthetic teixobactin. An additional observation was that the amount of swelling (edema) and inflammation that is part of the infection was quickly resolving with teixobactin. This additional anti-inflammatory effect of teixobactin is an asset that will be a necessity, when it comes to treating infections in patients.
At this point there have been no clinical trials. This is the next step before physicians can prescribe teixobactin for their patients. Dr. Singh said, “We are probably around six to ten years away from a drug that doctors can prescribe to patients”.
New antibiotic treats
antibiotic resistant tuberculosisIn addition to teixobactin there is another story that gives hope for cases of resistant tuberculosis. In an Iranian publication from August 2017 it is described how compounds from the Persian shallot have full antibiotic activity against known drug resistant E.coli strains.
The same antibiotic derived from Persian shallot is also effective against resistant tuberculosis. Dr. Sanjib Bhakta and Professor Gibbons from Great Britain said that their ability to synthesize the effective antibiotics is a great breakthrough. Prof. Gibbons said: “Natural products from plants and microbes have enormous potential as a source of new antibiotics. Nature is an amazingly creative chemist, and it is likely that plants such as the Persian shallot produce these chemicals as a defence against microbes in their environment. Dr. Bhakta and I will be dedicating our research to discovering new antibiotics and understanding how they function.”