Breaking News
February 16, 2019 - Therapeutic endoscopy has an expanding role in the treatment of IBD
February 16, 2019 - Catalyst Biosciences Presents Updated Data from Its Phase 2/3 Trial of Subcutaneous Marzeptacog Alfa (Activated) in Individuals with Hemophilia A or B with Inhibitors at the 12th Annual EAHAD Congress
February 16, 2019 - Rerouting nerves during amputation reduces phantom limb pain before it starts
February 16, 2019 - A Hormone Produced When We Exercise Might Help Fight Alzheimer’s
February 16, 2019 - Millions of British people breathe toxic air travelling to GPs
February 16, 2019 - Conformance of genetic characteristics found to be crucial for longer preservation of kidney graft
February 16, 2019 - Researchers use optogenetic tool to control, visualize receptor signals in neural cells
February 16, 2019 - New reversible antiplatelet therapy could reduce risk of blood clots, prevent cancer metastasis
February 16, 2019 - Testosterone is not the only hormone needed for penis development
February 16, 2019 - FDA Advisory Committee Recommends Approval of Spravato (esketamine) Nasal Spray for Adults with Treatment-Resistant Depression
February 15, 2019 - Heart surgery technology developed at Baptist Health debuts after years of secrecy
February 15, 2019 - Prescription Opioids Double Risk of Triggering Fatal Car Crash
February 15, 2019 - New study helps doctors better understand high blood pressure in pregnant women
February 15, 2019 - Beta wave control in Parkinson’s diseased brain could be a potential therapy
February 15, 2019 - Media representations of love may justify gender-based violence in young people
February 15, 2019 - Yoga May Help With Rheumatoid Arthritis Symptoms, Severity
February 15, 2019 - Obstructive sleep apnea linked to inflammation, organ dysfunction
February 15, 2019 - Master your mind: A challenge from WELL for Life
February 15, 2019 - Why Some Brain Tumors Respond to Immunotherapy
February 15, 2019 - Must-Reads Of The Week From Brianna Labuskes
February 15, 2019 - Researchers uncover novel mechanism and potential new therapeutic target for Alzheimer’s
February 15, 2019 - Genetic variations in a fourth gene associated with higher ALL risk in Hispanic children
February 15, 2019 - Disruptive behavioral problems in kindergarten linked with lower employment earnings in adulthood
February 15, 2019 - New bioengineered device enhances the production of T-cells
February 15, 2019 - HDL proteome behaves like a tiny Velcro ball that is rolling on surfaces
February 15, 2019 - Puerto Rican children more likely to have poor or decreasing use of asthma inhalers
February 15, 2019 - Quality of patient care does not improve after physician-hospital integration
February 15, 2019 - Synopsys release new software for implant design and patient-specific planning
February 15, 2019 - 6 out of 10 hip replacements last 25 years or longer
February 15, 2019 - Health Tip: What You Should Know About Antibiotics
February 15, 2019 - New research challenges medical consensus that adenoids and tonsils significantly shrink during teenage years
February 15, 2019 - Discovery of weakness in a rare cancer could be exploited with drugs
February 15, 2019 - UVA scientists find potential explanation for mysterious cell death in Alzheimer’s, Parkinson’s
February 15, 2019 - New rules requiring female athletes to lower testosterone levels are based on flawed data
February 15, 2019 - Researchers comprehensively sequence the human immune system
February 15, 2019 - Researchers study animal venoms to identify new medicines for treating diseases
February 15, 2019 - Movement of wrist bones revealed by MRI and computer modeling
February 15, 2019 - Philips introduces new premium digital X-ray room to help shorten patient wait times
February 15, 2019 - Women fare worse than men following aortic heart surgery, study finds
February 15, 2019 - High-protein and low-calorie diet helps older adults lose weight safely, shows study
February 15, 2019 - Drug microdosing effects may not measure up to big expectations
February 15, 2019 - Discharged, Dismissed: ERs Often Miss Chance To Set Overdose Survivors On ‘Better Path’
February 15, 2019 - A digitized lab environment to be showcased at smartLAB 2019
February 15, 2019 - Scientists uncover main mechanisms of fluconazole drug resistance
February 15, 2019 - New study seeks to understand how colibactin causes cancer
February 15, 2019 - Photoacoustic imaging accurately measures the temperature of deep tissues
February 15, 2019 - Large study finds no association between phthalate exposure and breast cancer risk
February 15, 2019 - New research explains presence of ‘natural’ magnetism in human cells
February 15, 2019 - Bio-Rad launches new digital PCR system and kit for monitoring treatment response in CML patients
February 15, 2019 - Excessive daytime sleepiness in OSA patients linked to greater risk for cardiovascular diseases
February 15, 2019 - Scientists shed light on damaging cell effects linked to aging
February 15, 2019 - Celiac disease may be caused by stomach bug in childhood
February 15, 2019 - NHS performance figures highlight the true scale of Emergency Department crisis
February 15, 2019 - High intensity exercise may improve health by increasing gut microbiota diversity
February 15, 2019 - Apellis’ APL-2 Receives Orphan Drug Designation from the FDA for the Treatment of Autoimmune Hemolytic Anemia
February 15, 2019 - Couples creating art or playing board games release ‘love hormone’
February 15, 2019 - Glimpsing The Future At Gargantuan Health Tech Showcase
February 15, 2019 - Common herbicide found to increase the risk of lymphoma
February 15, 2019 - Over-abundance of energy to cells could increase cancer risk
February 15, 2019 - Oxford Genetics appoints Jocelyne Bath as new Chief Operating Officer
February 15, 2019 - Castration-resistant metastatic prostate cancer responds to combination of immune checkpoint inhibitors
February 15, 2019 - Large-scale clinical trial begins to study liver transplantation between people with HIV
February 15, 2019 - Cannabis use among adolescents linked with increased risk of depression in adulthood
February 15, 2019 - Fractures, head injuries common in electric scooter accidents, UCLA study finds
February 15, 2019 - Prenatal maternal depression has important consequences for infant temperament, study shows
February 15, 2019 - Stereotactic body radiotherapy effective in treating men with low- or intermediate-risk prostate cancer
February 15, 2019 - Zogenix Submits New Drug Application to U.S. Food & Drug Administration for Fintepla for the Treatment of Dravet Syndrome
February 15, 2019 - Certain birthmarks warrant quick treatment, pediatricians say
February 15, 2019 - New machine learning method predicts if atypical ductal hyperplasia will turn cancerous
February 15, 2019 - Whole-genome sequencing and sharing real-time data could limit spread of foodborne bacteria
February 15, 2019 - FDA warns doctor for illegally marketing unapproved implantable device
February 15, 2019 - New injury documentation tool may provide better evidence for elder abuse cases
February 15, 2019 - Physiological age is a better predictor of survival than chronological age, shows study
February 15, 2019 - New study reveals high success rate for hip and knee replacements
February 15, 2019 - Prenatal exposures to BPA may pose threat to human ovarian function
February 15, 2019 - Suspicious spots on the lungs of children with rhabdomyosarcoma do not behave like metastases
February 15, 2019 - Diet drinks daily could raise stroke risk says study
February 15, 2019 - Many Systematic Reviews Do Not Fully Report Adverse Events
February 15, 2019 - Seven tips to protect your child from burns
February 15, 2019 - Keynote speakers announced for CBD Expo MIDWEST
MIT researchers develop antimicrobial peptides from South American wasp’s venom

MIT researchers develop antimicrobial peptides from South American wasp’s venom

image_pdfDownload PDFimage_print

Altered peptides from a South American wasp’s venom can kill bacteria but are nontoxic to human cells

The venom of insects such as wasps and bees is full of compounds that can kill bacteria. Unfortunately, many of these compounds are also toxic for humans, making it impossible to use them as antibiotic drugs.

After performing a systematic study of the antimicrobial properties of a toxin normally found in a South American wasp, researchers at MIT have now created variants of the peptide that are potent against bacteria but nontoxic to human cells.

In a study of mice, the researchers found that their strongest peptide could completely eliminate Pseudomonas aeruginosa, a strain of bacteria that causes respiratory and other infections and is resistant to most antibiotics.

“We’ve repurposed a toxic molecule into one that is a viable molecule to treat infections,” says Cesar de la Fuente-Nunez, an MIT postdoc. “By systematically analyzing the structure and function of these peptides, we’ve been able to tune their properties and activity.”

De la Fuente-Nunez is one of the senior authors of the paper, which appears in the Dec. 7 issue of the journal Nature Communications Biology. Timothy Lu, an MIT associate professor of electrical engineering and computer science and of biological engineering, and Vani Oliveira, an associate professor at the Federal University of ABC in Brazil, are also senior authors. The paper’s lead author is Marcelo Der Torossian Torres, a former visiting student at MIT.

Venomous variants

As part of their immune defenses, many organisms, including humans, produce peptides that can kill bacteria. To help fight the emergence of antibiotic-resistant bacteria, many scientists have been trying to adapt these peptides as potential new drugs.

The peptide that de la Fuente-Nunez and his colleagues focused on in this study was isolated from a wasp known as Polybia paulista. This peptide is small enough — only 12 amino acids — that the researchers believed it would be feasible to create some variants of the peptide and test them to see if they might become more potent against microbes and less harmful to humans.

“It’s a small enough peptide that you can try to mutate as many amino acid residues as possible to try to figure out how each building block is contributing to antimicrobial activity and toxicity,” de la Fuente-Nunez says.

Like many other antimicrobial peptides, this venom-derived peptide is believed to kill microbes by disrupting bacterial cell membranes. The peptide has an alpha helical structure, which is known to interact strongly with cell membranes.

In the first phase of their study, the researchers created a few dozen variants of the original peptide and then measured how those changes affected the peptides’ helical structure and their hydrophobicity, which also helps to determine how well the peptides interact with membranes. They then tested these peptides against seven strains of bacteria and two of fungus, making it possible to correlate their structure and physicochemical properties with their antimicrobial potency.

Based on the structure-function relationships they identified, the researchers then designed another few dozen peptides for further testing. They were able to identify optimal percentages of hydrophobic amino acids and positively charged amino acids, and they also identified a cluster of amino acids where any changes would impair the overall function of the molecule.

Fighting infection

To measure the peptides’ toxicity, the researchers exposed them to human embryonic kidney cells grown in a lab dish. They selected the most promising compounds to test in mice infected with Pseudomonas aeruginosa, a common source of respiratory and urinary tract infections, and found that several of the peptides could reduce the infection. One of them, given at a high dose, could eliminate it completely.

“After four days, that compound can completely clear the infection, and that was quite surprising and exciting because we don’t typically see that with other experimental antimicrobials or other antibiotics that we’ve tested in the past with this particular mouse model,” de la Fuente-Nunez says.

The researchers have begun creating additional variants that they hope will be able to clear infections at lower doses. De la Fuente-Nunez also plans to apply this approach to other types of naturally occurring antimicrobial peptides when he joins the faculty of the University of Pennsylvania next year.

“I do think some of the principles that we’ve learned here can be applicable to other similar peptides that are derived from nature,” he says. “Things like helicity and hydrophobicity are very important for a lot of these molecules, and some of the rules that we’ve learned here can definitely be extrapolated.”

Source:

http://news.mit.edu/2018/repurpose-wasp-venom-antibiotic-drug-1207

Tagged with:

About author

Related Articles