Isabel and Alice publish paper on a new way to detect antimicrobial resistance

A new, quicker way of detecting antibiotic resistance in bacteria has been developed by a team of scientists from the EPSRC funded interdisciplinary research collaboration, i-sense.

Isabel Bennett and Alice Pyne along with collaborators at UCL have developed a new technique that uses nanotechnology to detect antibiotic resistance in approximately 45 minutes.

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The standard method for detecting resistance is a relatively slow process that typically takes between 12 and 24 hours. The ability to reduce this time could significantly help the ongoing battle against antibiotic-resistant bacteria - a problem which is predicted to cause 10 million deaths per year and cost the global economy $100 trillion by 2050.

Speeding up the time it takes to identify antibiotic-resistant bacteria could improve our ability to prescribe antibiotics correctly and reduce the misuse of antibiotic treatments - a key step in the fight against antibiotic resistance.

The new method was developed by Isabel at UCL in collaboration with Alice and Prof. Rachel McKendry, also from UCL, and uses a new Atomic Force Microscopy (AFM) detection system. 

Our method allowed us to quickly differentiate between resistant and sensitive phenotypes in multiple strains of E. coli, a bacteria implicated in a number of challenging infections including UTIs.

Dr Isabel Bennett

UCL

This method uses a nanomechanical cantilever sensor together with a laser to detect single bacterial cells as they pass through the laser’s focus, which provides a simple readout of antibiotic resistance by detecting growth (resistant) or death (sensitive) of the bacteria.

By placing a reflective surface - a small stiff cantilever - in a filtered growth medium in a petri dish and reflecting a laser off it onto a photodiode detector, it is possible to detect bacteria as they pass through the path of the laser, therefore altering the signal at the detector.

Following the addition of the antibiotic to the petri dish, the study has shown that it is possible to detect whether fewer bacteria interfere with the laser beam, thereby indicating cell death in the antibiotic-sensitive bacteria.

The new technique developed by Isabel builds on an AFM method from a previous study, however this method doesn’t require the bacteria to be immobilised - making the new detection system much faster.

Isabel said: “Our method allowed us to quickly differentiate between resistant and sensitive phenotypes in multiple strains of E. coli, a bacteria implicated in a number of challenging infections including UTIs.”

Alice added: “We were able to show that our faster method was able to reproduce values from gold standard measurements, such as MIC’s in a fraction of the time.”

The study - Cantilever Sensors for Rapid Optical Antimicrobial Sensitivity Testing - was conducted by Dr Isabel Bennett as part of her PhD supervised by Dr Alice Pyne and Professor Rachel McKendry.

The research by the all-female team of scientists is published in the journal ACS Sensors. The journal has published an interview with Dr Bennett following the paper being selected as an ACS editors choice.


Read the paper here

EMBO DNA topology and topoisomerase meeting in Les Diablerets

EMBO DNA topology and topoisomerase meeting in Les Diablerets

I was lucky enough to have been selected to give a talk at the 2019 EMBO workshop on DNA topology and topoisomerases in genome dynamics in Les Diablerets. This was my second time attending this meeting, and it was particularly exciting for me, as I was returning to present data that came from a new collaboration with James Provan, Sean Colloms and Andrzej Stasiak which came from the last EMBO meeting.

Isabel passes her viva! Congratulations Dr Bennett

Isabel passes her viva! Congratulations Dr Bennett

Congratulations to Dr Bennett on passing (and enjoying) her viva, and thank you to her brilliant examiners, Til Bachmann and Carmel Curtis for making it such a great experience. Its been an absolute pleasure working with Isabel for the past 5 years - I’m excited to see what the future has in store for you.

A new chapter - Alice moves to the University of Sheffield to take up a lectureship in the Department of Materials Science

After almost a decade, Alice is leaving UCL to take up a position at the University of Sheffield in the Department of Materials Science and Engineering.

I am really excited to start a new chapter in my research, continuing on with all of my current collaborators, but also to find new collaborators, both in Engineering and Materials Science, and throughout the University of Sheffield. This should be made a little easier by the growing DNA presence at the University of Sheffield, which I encountered at #NAF2019, and whom I hope to meet more of through SInFoNiA.

I can’t wait to get started, and to meet my new colleagues. I’d also like to thank everyone at UCL who’s contributed to my journey there, its been an incredible place to learn and work. I look forward to visiting, I will have an honorary position there, so will be back often!

 

The Robert Hadfield Building, University of Sheffield

The 15th Nucleic Acids Forum #NAF2019

The 15th Nucleic Acids Forum #NAF2019

NAF 2019 was a brilliant meeting, organised by David Rueda, at the Royal Society of Chemistry. There were a series of brilliant talks, with an engaged and interested audience. Alice’s talk on supercoiling in DNA minicircles - ‘Untangling DNA, one molecule at a time’ - was well received, and she was awarded a model of the structure of the BDNA double helix, fabricated by Molecular Models. Thanks to the Nucleic Acids Group, David Rueda and his lab for organising an inspiring day of talks. We’re already looking forward to next year!

Caught in the act - catching the membrane attack complex on camera

Caught in the act - catching the membrane attack complex on camera

Our immune system relies on nanomachines, such as the membrane attack complex (MAC) to kill invasive bacteria in our blood. Our research, published in the EMBO journal and Nature Communications, provides us with a better understanding of how the immune system kills bacteria. This may guide the development of new therapies that harness the immune system against bacterial infections, and strategies that repurpose the immune system to act against other rogue cells in the body.

Untangling DNA - one molecule at a time at BIRS: The Topology of Nucleic Acids

Untangling DNA - one molecule at a time at BIRS: The Topology of Nucleic Acids

Alice is visiting the Banff International Research Station (BIRS) in Banff, Alberta to present our work on DNA topology at The Topology of Nucleic Acids: Research at the Interface of Low-Dimensional Topology, Polymer Physics and Molecular Biology.

If you’d like to see the talk, you can watch it here.

'Targeting Twist' at the Physics of Life PolNET2 2018 Symposium

'Targeting Twist' at the Physics of Life PolNET2 2018 Symposium

On the 10th December 2018, Kavit attended the ‘Physics of Life PoLNET2 2018 Symposium: Molecules, Mechanics, Medicine and More!’ at the University of York. The interdisciplinary symposium aimed to showcase collaborative projects across Biology and Physics with discussions ranging from evolution to epigenetics.