Breaking News
February 22, 2019 - AbbVie Announces New Drug Application Accepted for Priority Review by FDA for Upadacitinib for Treatment of Moderate to Severe Rheumatoid Arthritis
February 22, 2019 - Nature versus nurture and addiction
February 22, 2019 - New website connects researchers with data experts, resources | News Center
February 22, 2019 - Today’s Concerns About Drug Prices Echo The Past
February 22, 2019 - CT and Doppler equipment have low accuracy in detecting cerebral vasospasm and ischemia
February 22, 2019 - Study finds out similarity in function between healthy retina cell and tumor cell
February 22, 2019 - CWRU awarded NIH grant to identify effective treatments for intimate partner violence
February 22, 2019 - Oncotype DX Not Cost-Effective for Low-Risk Breast Cancer
February 22, 2019 - Scientists discover new type of immune cells that are essential for forming heart valves
February 22, 2019 - Talk About Déjà Vu: Senators Set To Re-Enact Drug Price Hearing Of 60 Years Ago
February 22, 2019 - Genetic defect linked to pediatric liver disease identified
February 22, 2019 - New cellular atlas could provide a deeper insight into blinding diseases
February 22, 2019 - Growing number of cancer survivors, fewer providers point to challenge in meeting care needs
February 22, 2019 - Innovative compound offers a new therapeutic approach to treat multiple sclerosis
February 22, 2019 - $1.5 million grant to develop opioid treatment program for jail detainees
February 22, 2019 - FDA’s new proposed rule would update regulatory requirements for sunscreen products in the U.S
February 22, 2019 - Most Hip, Knee Replacements Last Decades, Study Finds
February 22, 2019 - Wellness problems prevalent among ob-gyn residents
February 22, 2019 - In the Spotlight: “The world is your oyster in geriatrics”
February 22, 2019 - Successful testing of multi-organ “human-on-a-chip” could replace animals as test subjects
February 22, 2019 - Analysis of cervical precancer shows decline in two strains of HPV
February 22, 2019 - Sugary stent eases suturing of blood vessels
February 22, 2019 - From surgery to psychiatry: A medical student reevaluates his motivations
February 22, 2019 - Is New App From Feds Your Answer To Navigating Medicare Coverage? Yes And No
February 22, 2019 - New pacemakers powered by heartbeats could reduce need for surgery
February 22, 2019 - The United States records highest drug overdose death rates
February 22, 2019 - Phase 1 data reinforce safety profile of new drug for treating Duchenne muscular dystrophy
February 22, 2019 - Vitamin D supplementation less effective in the presence of obesity, shows study
February 22, 2019 - CPRIT awards nearly $20 million to The University of Texas MD Anderson Cancer Center
February 22, 2019 - Sarepta Announces FDA Acceptance of Golodirsen (SRP-4053) New Drug Application for Patients with Duchenne Muscular Dystrophy Amenable to Skipping Exon 53
February 22, 2019 - An institutional effort to reduce the amount of opioids prescribed following lumbar surgery
February 22, 2019 - Family-history-based models perform better than non-family-history based models
February 22, 2019 - Failure to take statins leads to higher mortality rates | News Center
February 22, 2019 - New study explains why some patients report phantom sensations after limb amputation
February 22, 2019 - First motor-controlled heart valves implanted by Mainz University Medical Center
February 22, 2019 - Novel preclinical model mimics persistent interneuron loss seen in preterm infants
February 22, 2019 - Global health burden of glaucoma has increased, study reveals
February 22, 2019 - A holistic approach key to minimize treatment complexity in patients with interstitial lung disease
February 22, 2019 - 1 in 10 middle-aged Chinese adults are at high risk for heart disease, finds study
February 22, 2019 - More than half a million breast cancer patient’s lives saved by improvements in treatment
February 22, 2019 - Study finds no evidence that tougher policies prevent teenage cannabis use
February 22, 2019 - New blood test detects genetic disorders in fetuses
February 22, 2019 - Lower Self-Perception Observed in Children With Amblyopia
February 22, 2019 - Up to 15 percent of children have sleep apnea, yet 90 percent go undiagnosed
February 22, 2019 - Rare pulmonary defect prompts parents’ nationwide search for answers | News Center
February 22, 2019 - Lesbian and bisexual women at greater risk of being overweight, study finds
February 22, 2019 - UQ research may explain why vitamin D is essential for brain health
February 22, 2019 - Heart Attacks Rising Among Younger Women
February 22, 2019 - How your smartphone is affecting your relationship
February 22, 2019 - Orthopaedic surgeon receives prestigious award, $10 million grant | News Center
February 22, 2019 - New sepsis test could save thousands of lives
February 22, 2019 - Cervical cancer could be eradicated by 2100
February 21, 2019 - Sustained smoking cessation can lower risk of seropositive RA
February 21, 2019 - Thousands with chronic UTIs are not receiving the treatment they need
February 21, 2019 - Are teens getting high on social media? The surprising study seeking the pot-Instagram link
February 21, 2019 - Stanford expands biobank services | News Center
February 21, 2019 - Scientists identify link between drinking contexts and early onset intoxication among adolescents
February 21, 2019 - Strong social support may reduce cardiovascular disease risk in postmenopausal women
February 21, 2019 - Rapid expansion of interventions could prevent up to 13 million cases of cervical cancer within 50 years
February 21, 2019 - Motif Bio Receives Complete Response Letter From The FDA
February 21, 2019 - Researchers map previously unknown disease in children
February 21, 2019 - A skeptical look at popular diets: Going gluten-free
February 21, 2019 - Podcast: KHN’s ‘What The Health?’ How Safe Are Your Supplements?
February 21, 2019 - Factors associated with increased risk of developing surgical site infections
February 21, 2019 - Anticipatory signals in eye movements can help measure attentive capacity, learning with greater precision
February 21, 2019 - Study explores daily exposure to indoor air pollutants
February 21, 2019 - Evening exercise does not negatively affect sleep, may also reduce hunger
February 21, 2019 - Artificial intelligence technique can be used to identify alcohol misuse in trauma setting
February 21, 2019 - Overweight, obesity in adolescence associated with increased risk of renal cancer later in life
February 21, 2019 - BGU develops new AI platform for monitoring and predicting ALS progression
February 21, 2019 - Researchers discover a new promising target to improve HIV vaccines
February 21, 2019 - Brief Anesthesia in Infancy Does Not Mar Neurodevelopment
February 21, 2019 - Gaming system helps with autism diagnosis
February 21, 2019 - Heart Disease: Six Things Women Should Know
February 21, 2019 - More States Say Doctors Must Offer Overdose Reversal Drug Along With Opioids
February 21, 2019 - Researchers explore case studies focused on industries that kill more people than employed
February 21, 2019 - Only half of GP practice buildings are fit for purpose
February 21, 2019 - Intense exercise, fasting and hormones can enhance waste-protein removal, study shows
February 21, 2019 - Scientists can monitor brain activity to predict epileptic seizures few minutes in advance
February 21, 2019 - Study quantifies hepatic and intestinal mRNA expression of Ugt isoforms in rats
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