Nav: Home

How bacteria acquire antibiotic resistance in the presence of antibiotics

May 23, 2019

A new study's disconcerting findings reveal how antibiotic resistance is able to spread between bacteria cells despite the presence of antibiotics that should prevent them from growing. The results reveal the ability for previously drug-sensitive bacteria to survive exposure to antibiotics long enough to express resistance genes they've just acquired - effectively rendering them immune to antibiotic drugs. The mechanisms underlying this process, including a drug-jettisoning pump found in virtually all bacteria, represent targets for combatting antibiotic resistance. Bacteria can acquire new genes by receiving snippets of DNA (plasmids) from other bacteria through horizontal gene transfer mechanisms like bacterial conjugation, which often confer genetic advantages, including antibiotic resistance, in the recipient cell. A vast array of conjugative plasmids have been identified in drug-resistant bacteria, which carry one or more resistance genes to most - if not all - clinically used antibiotic drugs. While bacterial conjugation is the primary method by which drug-resistance is spread in bacterial pathogens, many aspects of the process are poorly understood and remain to be described in vivo. Using live-cell microscopy and a novel system for visualizing the transmission of plasmids in real time and at the cellular level, Sophie Nolivos and colleagues tracked the transfer of a plasmid carrying a tetracycline resistance gene from a drug-resistant E. coli donor bacterium to another bacterium initially susceptible to the antibiotic drug. Shortly after the plasmid-encoded genes were transferred, TetA, a protein that mediates tetracycline resistance, was rapidly produced in the recipient bacterium. Unexpectedly, however, Nolivos et al. observed that previously antibiotic-sensitive bacteria were still able to aquire tetracycline resistance through plasmid echange and produce the TetA resistance factor, despite being exposed to the drug. The results show that this ability stems from help from the AcrAB-TolC multidrug efflux pump of bacteria, which buys time for TetA translation by keeping tetracycline concentration below toxic levels within the bacterial cell. In a related Perspective, Vanessa Povolo and Martin Ackerman discuss the study in detail.

American Association for the Advancement of Science

Related Bacteria Articles:

Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.
How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.
The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?
Detecting bacteria in space
A new genomic approach provides a glimpse into the diverse bacterial ecosystem on the International Space Station.
Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.
Bacteria uses viral weapon against other bacteria
Bacterial cells use both a virus -- traditionally thought to be an enemy -- and a prehistoric viral protein to kill other bacteria that competes with it for food according to an international team of researchers who believe this has potential implications for future infectious disease treatment.
Drug diversity in bacteria
Bacteria produce a cocktail of various bioactive natural products in order to survive in hostile environments with competing (micro)organisms.
Bacteria walk (a bit) like we do
EPFL biophysicists have been able to directly study the way bacteria move on surfaces, revealing a molecular machinery reminiscent of motor reflexes.
Using bacteria to create a water filter that kills bacteria
Engineers have created a bacteria-filtering membrane using graphene oxide and bacterial nanocellulose.
Probiotics are not always 'good bacteria'
Researchers from the Cockrell School of Engineering were able to shed light on a part of the human body - the digestive system -- where many questions remain unanswered.
More Bacteria News and Bacteria Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab