Breaking News
January 21, 2019 - Researchers uncover specific microbial signatures of intestinal disease
January 21, 2019 - Plan Your Plate | NIH News in Health
January 21, 2019 - Fecal occult blood test may improve CRC outcomes in some
January 21, 2019 - Mount Sinai joins with Paradigm and ReqMed to repurpose drug for treatment of MPS
January 21, 2019 - FDA Advisory Committee Votes on Zynquista (sotagliflozin) as Treatment for Adults with Type 1 Diabetes
January 21, 2019 - The causes and complications of snoring
January 21, 2019 - Placenta adapts and compensates when pregnant mothers have poor diets or low oxygen
January 21, 2019 - New implant could restore the transmission of electrical signals in injured central nervous system
January 21, 2019 - Rapid-acting fentanyl test strips found to be effective at reducing overdose risk
January 21, 2019 - Coronary Artery Calcium May Help Predict CVD in South Asians
January 21, 2019 - The mystery of the super-ager
January 21, 2019 - Scientists develop smart microrobots that can change shape depending on their surroundings
January 21, 2019 - Keep Moving to Keep Brain Sharp in Old Age
January 21, 2019 - Despite progress, gay fathers and their children still structurally stigmatized
January 21, 2019 - New drug for treating liver parasites in vivax malaria
January 21, 2019 - Merck recognized with 2018 Life Science Industry Award for best use of social media
January 21, 2019 - Coeur Wallis equips the canton of Valais with 260 SCHILLER defibrillators
January 21, 2019 - Scientists propose quick and pain-free method for diagnosing kidney cancer
January 21, 2019 - Signs of memory loss could point to hearing issues
January 21, 2019 - HeartFlow Analysis shows highest diagnostic performance for detecting coronary artery disease
January 21, 2019 - How Much Caffeine is Too Much?
January 21, 2019 - Take a timeout before you force your child to apologize
January 21, 2019 - Scientists design two AI algorithms to improve early detection of cognitive impairment
January 21, 2019 - Novel therapy for children with chronic hormone deficiency provides lifeline for parents
January 21, 2019 - Bioethicists call for oversight of poorly regulated, consumer-grade neurotechnology products
January 21, 2019 - Study shows hereditary hemochromatosis behind many cancers and joint diseases
January 21, 2019 - Short bouts of stairclimbing throughout the day can improve cardiovascular health
January 20, 2019 - Liver Transplant Survival May Improve With Race Matching
January 20, 2019 - Study implicates hyperactive immune system in aging brain disorders
January 20, 2019 - Cancer Diagnosis May Quadruple Suicide Risk
January 20, 2019 - Parkinson’s disease experts devise a roadmap
January 20, 2019 - Research brings new hope to treating degenerative brain diseases
January 20, 2019 - Scientists pinpoint a set of molecules that wire the body weight center of the brain
January 20, 2019 - Researchers get close to developing elusive blood test for Alzheimer’s disease
January 20, 2019 - UCLA researchers demonstrate new technique to develop cancer-fighting T cells
January 20, 2019 - Researchers discover how cancer cells avoid genetic meltdown
January 20, 2019 - Exercise makes even the ‘still overweight’ healthier: study
January 20, 2019 - University of Utah to establish first-of-its-kind dark sky studies minor in the US
January 20, 2019 - School-based nutritional programs reduce student obesity
January 20, 2019 - Improved maternity care practices in the southern U.S. reduce racial inequities in breastfeeding
January 20, 2019 - New enzyme biomarker test indicates diseases and bacterial contamination
January 20, 2019 - Republican and Democratic governors have different visions to transform health care, say researchers
January 20, 2019 - Researchers discover that spin flips happen in only half a picosecond in the course of a chemical reaction
January 20, 2019 - Suicide Risk Up More Than Fourfold for Cancer Patients
January 20, 2019 - Doctors find 122 nails in Ethiopian’s stomach
January 20, 2019 - UV disinfection technology eliminates up to 97.7% of pathogens in operating rooms
January 20, 2019 - Researchers discover mechanism which drives leukemia cell growth
January 20, 2019 - AHA: Infection as a Baby Led to Heart Valve Surgery for Teen
January 20, 2019 - Injection improves vision in a form of childhood blindness
January 20, 2019 - Multiple sclerosis therapies delay progression of disability
January 20, 2019 - New study finds infrequent helmet use among bike share riders
January 20, 2019 - Clearing up information about corneal dystrophies
January 20, 2019 - Researchers describe new behavior in energy metabolism that refutes existing evidence
January 20, 2019 - New study takes first step toward treating endometriosis
January 20, 2019 - Researchers find how GREB1 gene promotes resistance to prostate cancer treatments
January 20, 2019 - Replacing Sitting Time With Activity Lowers Mortality Risk
January 20, 2019 - A simple, inexpensive intervention makes birth safer for moms and babies in parts of Africa
January 19, 2019 - New anti-inflammatory compound acts as ‘surge protector’ to reduce cancer growth
January 19, 2019 - Significant flaws found in recently released forensic software
January 19, 2019 - New Leash on Life? Staying Slim Keeps Pooches Happy, Healthy
January 19, 2019 - Men and women remember pain differently
January 19, 2019 - Rising air pollution linked with increased ER visits for breathing problems
January 19, 2019 - Study uses local data to model food consumption patterns among Seattle residents
January 19, 2019 - The brain’s cerebellum plays role in controlling reward and social behaviors, study shows
January 19, 2019 - Relationship between nurse work environment and patient safety
January 19, 2019 - Pioneering surgery restores movement to children paralyzed by acute flaccid myelitis
January 19, 2019 - Genetic variants linked with risk tolerance and risky behaviors
January 19, 2019 - New research provides better understanding of our early human ancestors
January 19, 2019 - First-ever tailored reporting guidance to improve patient care and outcomes
January 19, 2019 - 4.6 percent of Massachusetts residents have opioid use disorder
January 19, 2019 - New study suggests vital exhaustion as risk factor for dementia
January 19, 2019 - New antibiotic discovery heralds breakthrough in the fight against drug-resistant bacteria
January 19, 2019 - Ural Federal University scientists synthesize a group of multi-purpose fluorophores
January 19, 2019 - Researchers identify new therapeutic target in the fight against chronic liver diseases
January 19, 2019 - Preparation, characterization of Soyasapogenol B loaded onto functionalized MWCNTs
January 19, 2019 - FDA Approves Ontruzant (trastuzumab-dttb), a Biosimilar to Herceptin
January 19, 2019 - Tobacco use linked with higher use of opioids and sedatives
January 19, 2019 - Study delves deeper into developmental dyslexia
January 19, 2019 - Anti-vaccination movement one of the top health threats in 2019 says WHO
January 19, 2019 - Newly developed risk score more effective at identifying type 1 diabetes
IU researchers observe bacteria’s ‘DNA uptake’ process

IU researchers observe bacteria’s ‘DNA uptake’ process

image_pdfDownload PDFimage_print

Indiana University scientists have made the first direct observation of a key step in the process that bacteria use to rapidly evolve new traits, including antibiotic resistance.

Using methods invented at IU, researchers recorded the first images of bacterial appendages — over 10,000 times thinner than human hair — as they stretched out to catch DNA. These DNA fragments can then be incorporated into bacteria’s own genome through a process called DNA uptake or “horizontal gene transfer.”

The work is reported June 11 in the journal Nature Microbiology.

“Horizontal gene transfer is an important way that antibiotic resistance moves between bacterial species, but the process has never been observed before, since the structures involved are so incredibly small,” said senior author Ankur Dalia, an assistant professor in the IU Bloomington College of Arts and Sciences’ Department of Biology.

“It’s important to understand this process, since the more we understand about how bacteria share DNA, the better our chances are of thwarting it,” he added.

Nearly 1 million people are affected by antibiotic-resistant bacteria each year, according to the World Health Organization. WHO has found evidence of these strains in nearly 490,000 people with tuberculous and 500,000 people with other infectious diseases.

The bacterium used in the study was Vibrio cholerae, the microbe that causes cholera. The bacterial structures used to catch DNA in the environment are extremely thin, hair-like appendages called pili.

Although scientists were aware that pili play a role in DNA uptake, Dalia said that direct evidence demonstrating how they work was lacking until this study. In order to observe pili in action, the scientists used a new method invented at IU to “paint” both the pili and DNA fragments with special glowing dyes.

The team who developed the new method to label pili with dyes was led by IU Distinguished Professor Yves Brun and IU Ph.D. student Courtney Ellison.

The new study uses these dyes to reveal that pili act like microscopic “harpooners” that cast their line through pores in the cell’s wall to “spear” a stray piece of DNA at the very tip. The pili then “reel” the DNA into the bacterial cell through the same pore.

Dalia said the pore is so small that the DNA would need to fold in half to fit through the opening in the cell.

“It’s like threading a needle,” said Ellison, who is first author on the study. “The size of the hole in the outer membrane is almost the exact width of a DNA helix bent in half, which is likely what is coming across. If there weren’t a pilus to guide it, the chance the DNA would hit the pore at just the right angle to pass into the cell is basically zero.”

Next, Dalia said the team wants to study exactly how pili “hook” onto the DNA at just the right spot, especially since the protein involved in the process appears to interact with DNA in an entirely new way. They also look forward to applying their pili labeling method to study other functions played by these diverse bacterial structures.

“These are really versatile appendages,” Dalia said. “This method invented at IU is really opening up our basic understanding about a whole range of bacterial functions.”

Source:

https://news.iu.edu/stories/2018/06/iub/releases/11-scientists-watch-bacteria-harpoon-dna-to-speed-their-evolution.html

Tagged with:

About author

Related Articles