Breaking News
November 15, 2018 - Lilly Submits New Drug Application to the FDA for Lasmiditan for Acute Treatment of Migraine
November 15, 2018 - Heart failure patients shouldn’t stop meds even if condition improves: study
November 15, 2018 - Breakthrough research could lead to a new wave of cancer-fighting antibodies
November 15, 2018 - New study of tribe shows influence of Western diet and lifestyle on blood pressure
November 15, 2018 - Scientists harness power of natural killer cells to treat children with neuroblastoma
November 15, 2018 - Investigating foodborne disease outbreak in Bosnia and Herzegovina based on simulation game
November 15, 2018 - Recommendations Issued for Management of Bradycardia
November 15, 2018 - Benefit unclear due to a lack of suitable studies
November 15, 2018 - TAMEST recognizes UT Southwestern’s Ralph DeBerardinis for changing our understanding of cancer
November 15, 2018 - Researchers discover key factors behind intestinal inflammation in CVID patients
November 15, 2018 - CityU develops first microarrayed 3D neuronal culture platform
November 15, 2018 - Expert suggests ways to control uncomfortable vaginal symptoms in diabetic women
November 15, 2018 - New edition of Red Journal focuses on roles of imaging in radiation oncology
November 15, 2018 - Doctors Aren’t Promoting Breastfeeding’s Cancer-Protection Benefit
November 15, 2018 - Collection of demonstration projects highlights value of patient engagement in research
November 15, 2018 - Technique to ‘listen’ to a patient’s brain during tumour surgery
November 15, 2018 - Seven-year-old returns to life as a “normal, healthy child” following bone marrow transplant
November 15, 2018 - AMSBIO expands range of high quality FFPE cancer cell line controls
November 15, 2018 - Marijuana use by kidney donors has no effect on transplant outcomes
November 15, 2018 - Exploring NMR Spectroscopy Applications through Interesting Infographics
November 15, 2018 - Chapman University wins additional $2.9 million NIH grant to study Alzheimer’s disease
November 15, 2018 - Microgel powder reduces infection and promotes healing
November 15, 2018 - Suicidal patients with prescribed access to psychotropic drugs should be closely monitored
November 15, 2018 - Nitric oxide-releasing technology shows potential to reduce healing time of diabetic foot ulcers
November 15, 2018 - Mass shootings may trigger unnecessary blood donations
November 15, 2018 - From heart disease to cancer: New study tracks shift of county death rates
November 15, 2018 - Preventing falls with new sensor technology
November 15, 2018 - Promising technology could improve detection, diagnosis of fatal ovarian cancer
November 15, 2018 - AAP updates concussion recommendations for children and teens
November 15, 2018 - Two genomic tests help identify most effective treatment for breast cancer patients
November 15, 2018 - Researchers evaluate efficacy of salivary biomarkers for early detection of oral cancer
November 15, 2018 - NIH awards $3.5 million to continue development of robotic system for treating brain tumors
November 15, 2018 - Researchers succeed in building protein nanotubes from tiny scaffolds
November 15, 2018 - Rectal bleeding
November 15, 2018 - Nasal delivery of weight-loss hormone eases breathing problems in sleeping mice
November 15, 2018 - $9.6 million grant to fund research on vascular risk factors for brain aging, dementia | News Center
November 15, 2018 - Gum disease linked with diabetes
November 15, 2018 - Study identifies unique functional brain networks associated with ASD behaviors in infancy
November 15, 2018 - EU and industry-funded project aims to personalize diabetes treatment
November 15, 2018 - NIH researchers shed light on causes of HBV-associated acute liver failure
November 14, 2018 - FDA Alert: Implanted Pumps: Safety Communication
November 14, 2018 - Weight loss & acute Porphyria
November 14, 2018 - Researchers identify three sub-types of depression
November 14, 2018 - The puzzle of a mutated gene lurking behind many Parkinson’s cases | News Center
November 14, 2018 - The mystery viruses far worse than flu
November 14, 2018 - Research highlights physical changes in the brain of self-injuring teen girls
November 14, 2018 - Speed and error rate of DNA synthesis influenced by DNA structure
November 14, 2018 - Cranberry consumption modifies impact of animal-based diet on gut health
November 14, 2018 - £500,000 grant could pave way for new antibiotic to battle against drug-resistant superbugs
November 14, 2018 - Trump Administration Finalizes Birth Control Coverage Opt-Out
November 14, 2018 - Modern life offers children almost everything they need, except daylight
November 14, 2018 - Getting better: A patient is more than a collection of numbers
November 14, 2018 - 20 Americans Die Each Day Waiting For Organs
November 14, 2018 - First bifacial molecule can invade double-stranded DNA or RNA
November 14, 2018 - Study finds lack of safety data for using flowers in cooking
November 14, 2018 - Statistical methods play key role in predicting efficacy of new drugs
November 14, 2018 - Research explores how exercise may help fight drug addiction
November 14, 2018 - Health Tip: Limit Fat, Sugar and Salt in Your Child’s Diet
November 14, 2018 - CA 19-9 Blood Test (Pancreatic Cancer): MedlinePlus Lab Test Information
November 14, 2018 - Old drug could have new use helping sick premature babies
November 14, 2018 - Surgery, not antibiotics, should remain first-line treatment for appendicitis | News Center
November 14, 2018 - Researchers to develop sports-specific classification system for blind football
November 14, 2018 - Preschool children show awake responses to naptime nonsense words
November 14, 2018 - Researchers develop innovative treatment to repair damaged brain tissues
November 14, 2018 - Survey shows negative effect of vulvovaginal atrophy symptoms on quality of life for women
November 14, 2018 - Study sheds light on mechanisms that prevent autoimmune attack
November 14, 2018 - Sleep quality found to be worse for women who undergo surgical menopause
November 14, 2018 - One-hour cognitive behavioral therapy session reduces insomnia symptoms in prisoners
November 14, 2018 - New study provides deeper insight into chromosome segregation during mitosis
November 14, 2018 - Surgical menopause leads to more disrupted sleep than natural menopause
November 14, 2018 - Inhibition of one protein clears toxic clumps seen in Parkinson’s disease, study finds
November 14, 2018 - Appendix removal is linked to lower risk of Parkinson’s
November 14, 2018 - Lifting weights for less than an hour a week may reduce cardiovascular disease risk
November 14, 2018 - Pulmonary rehabilitation rarely received by hospitalized COPD patients despite health benefits
November 14, 2018 - New anti-HER2 drug shows promising anti-tumor activity in gullet, stomach and bowel cancers
November 14, 2018 - Regular head circumference assessment of preterm babies can help identify long-term IQ problems
November 14, 2018 - Brigham investigators examine opioid use among Massachusetts adolescents, prescription trends
November 14, 2018 - Study defines biomarker in response to treatment of castration-resistant prostate cancer
November 14, 2018 - Study identifies potential therapeutic strategy for patients with clear cell renal cancer
November 14, 2018 - Bausch Health Announces U.S. Launch of Bryhali (halobetasol propionate) Lotion, 0.01%, for Plaque Psoriasis In Adults
Scientists discover peptides that can be used as new antibiotic candidates

Scientists discover peptides that can be used as new antibiotic candidates

image_pdfDownload PDFimage_print

The human body produces many antimicrobial peptides that help the immune system fend off infection. Scientists hoping to harness these peptides as potential antibiotics have now discovered that other peptides in the human body can also have potent antimicrobial effects, expanding the pool of new antibiotic candidates.

In the new study, researchers from MIT and the University of Naples Federico II found that fragments of the protein pepsinogen, an enzyme used to digest food in the stomach, can kill bacteria such as Salmonella and E. coli.

The researchers believe that by modifying these peptides to enhance their antimicrobial activity, they may be able to develop synthetic peptides that could be used as antibiotics against drug-resistant bacteria.

“These peptides really constitute a great template for engineering. The idea now is to use synthetic biology to modify them further and make them more potent,” says Cesar de la Fuente-Nunez, an MIT postdoc and Areces Foundation Fellow, and one of the senior authors of the paper.

Other MIT authors of the paper, which appears in the Aug. 20 issue of the journal ACS Synthetic Biology, are Timothy Lu, an associate professor of electrical engineering and computer science and of biological engineering, and Marcelo Der Torossian Torres, a former visiting student.

Discovering new functions

Antimicrobial peptides, which are found in nearly all living organisms, can kill many microbes, but they are typically not powerful enough to act as antibiotic drugs on their own. Many scientists, including de la Fuente-Nunez and Lu, have been exploring ways to create more potent versions of these peptides, in hopes of finding new weapons to combat the growing problem posed by antibiotic-resistant bacteria.

In this study, the researchers wanted to explore whether other proteins found in the human body, outside of the previously known antimicrobial peptides, might also be able to kill bacteria. To that end, they developed a search algorithm that analyzes databases of human protein sequences in search of similarities to known antimicrobial peptides.

“It’s a data-mining approach to very easily find peptides that were previously unexplored,” de la Fuente-Nunez says. “We have patterns that we know are associated with classical antimicrobial peptides, and the search engine goes through the database and finds patterns that look similar to what we know makes up a peptide that kills bacteria.”

In a screen of nearly 2,000 human proteins, the algorithm identified about 800 with possible antimicrobial activity. In the ACS Synthetic Biology paper, the research team focused on the peptide pepsinogen, whose role is to break down proteins in food. After pepsinogen is secreted by cells that line the stomach, hydrochloric acid in the stomach mixes with pepsinogen, converting it into pepsin A, which digests proteins, and into several other small fragments.

Those fragments, which previously had no known functions, showed up as candidates in the antimicrobial screen.

Once the researchers identified those candidates, they tested them against bacteria grown in lab dishes and found that they could kill a variety of microbes, including foodborne pathogens, such as Salmonella and E. coli, as well as others, including Pseudomonas aeruginosa, which often infects the lungs of cystic fibrosis patients. This effect was seen at both acidic pH, similar to that of the stomach, and neutral pH.

“The human stomach is attacked by many pathogenic bacteria, so it makes sense that we would have a host defense mechanism to defend ourselves from such attacks,” de la Fuente-Nunez says.

More potent drugs

The researchers also tested the three pepsinogen fragments against a Pseudomonas aeruginosa skin infection in mice, and found that the peptides significantly reduced the infections. The exact mechanism by which the peptides kill bacteria is unknown, but the researchers’ hypothesis is that their positive charges allow the peptides to bind to the negatively charged bacterial membranes and poke holes in them, a mechanism similar to that of other antimicrobial peptides.

The researchers now hope to modify these peptides to make them more effective, so that they could be potentially used as antibiotics. They are also seeking new peptides from organisms other than humans, and they plan to further investigate some of the other human peptides identified by the algorithm.

“We have an atlas of all these molecules, and the next step is to demonstrate whether each of them actually has antimicrobial properties and whether each of them could be developed as a new antimicrobial,” de la Fuente-Nunez says.

Source:

http://news.mit.edu/2018/biological-engineers-discover-new-antibiotic-candidates-0820

Tagged with:

About author

Related Articles