The team - from Leeds' Astbury Centre for Structural Molecular Biology and Faculty of Biological Sciences - found that an antibiotic known as Rifamycin SV was able to prevent the protein b2microglobulin (b2m) from forming into fibrils. b2m is known to accumulate in renal dialysis patients and forms fibrils within the joints, causing extreme pain and arthritis.
By using a specialised analytical technique called ion mobility spectrometry-mass spectrometry (IMS-MS), the researchers were able to see at what stage of the process Rifamycin SV prevented amyloid fibril formation.
They believe the technique could enable potential drugs to be identified for the many other proteins which form amyloid fibrils, linked to a wide range of human disorders.
"Traditional drug design for diseases like Alzheimer's is incredibly difficult because the proteins you're trying to target are changing shape and structure all the time," explains University of Leeds Professor of Structural Molecular Biology, Sheena Radford. "It's like trying to consistently pick out one bead of a particular shape from box of potentially millions of similar beads. This new technique allows us to see the shape of the protein as it changes, so we can more easily identify exactly which part we need to target."
In their normal, folded state, proteins are unable to link together to form long fibrillar assemblies, but if they unfold, they expose areas where they can bind to each other. Initially they form small groups of two, three or four proteins, and then these link into long strands, which twist together to form fibrils.
Most analytical techniques can only show the mass of the protein or its make-up in terms of amino acids, neither of which changes as the protein unfolds. Others are unable to look at individual molecules within complex mixtures.
However, IMS-MS can measure the mass and shape of a protein, allowing researchers to watch the unfolding process and the aggregation into small groups and then assembly into the fibril and to find which of these species is able to bind a ligand and stop the assembly process.
In the research published today, researchers found that Rifamycin SV stopped the formation of protein fibrils by binding to an unfolded protein molecule with a particular shape, enabling for the first time, an unfolded protein of a particular shape to be identified as a target for the design of new inhibitors of fibril assembly.
"We're fortunate to be one of the few universities in the UK able to use IMS-MS to study amyloid fibril formation," says Professor of Biomolecular Mass Spectrometry, Alison Ashcroft, who specialises in this type of analysis. "Although fibrils take years to develop in the body, we are able to 'grow' them in hours in the lab. By using IMS-MS to help us map exactly how they are formed, we can better understand the mechanism by which it happens and - we hope - find ways to stop it."
Graham Askew, Simon Walker, BBSRC (Jan 2018), £699,781
Jennifer Tomlinson, Royal Society (Jan 2018), £512,801
Alex O'Neill and colleagues in Chemistry, BBSRC (Nov 2017), £431,865
Tom Bennett, BBSRC (Oct 2017), £523,679
Neil Ranson, Darren Tomlinson, BBSRC (Oct 2017), £494,318
Nikita Gamper, BBSRC (Oct 2017), £490,426
Amanda Bretman and colleagues from UEA, NERC (Oct 2017), £430,886
Juan Fontana, Rosetrees Trust consumables grant (Oct 2017), £22,500
Helen Miller, DSM Nutritional Products AG (Sep 2017), £69,988
Neil Ranson, Juan Fontana, Mark Harris, Michelle Peckham, Ralf Richter, Peter Stockley, Patricija Van Oosten-Hawle and colleagues in Engineering, FMH and MAPS, Wellcome Trust Equipment Call (Sep 2017), £418,000
Jamie Johnston, Physiological Society (Sep 2017), £10,000
Frank Sobott, Adrian Goldman, Mark Harris, Andrew Macdonald, Stephen Muench, Sheena Radford and colleagues in FMH and MAPS, Wellcome Trust Equipment Call (Aug 2017), £415,000
Ralf Richter, David Brockwell, Eric Hewitt, Jessica Kwok, Emanuele Paci and MAPS/FMH, BBSRC (Jun 2017), £600,000
Eric Blair, Adrian Whitehouse, Nicola Stonehouse, Alison Baker, Richard Bayliss, Joan Boyes, Ryan Seipke, Sally Boxall and MAPS/FMH, BBSRC (Jun 2017), £376,000
Stefan Kepinski, Yoselin Benitez-Alfonso, Tom Bennett, Michelle Peckham, BBSRC (Jun 2017), £331,000
Roman Tuma, Lars Jeuken, Paul Millner, Sheena Radford, Peter Stockley and MAPS/FMH, BBSRC (Jun 2017), £222,000
Vas Ponnambalam, Darren Tomlinson, Stephen Wheatcroft, BHF (May 2017), £107,878
Graham Askew in collaboration with Bangor University, BBSRC (Mar 2017), £477,383
Stephen Muench, BBSRC (Mar 2017), £132,945
Nic Stonehouse, MRC (Mar 2017), £906,341
Bill Kunin, Steve Sait, BBSRC (Mar 2017), £602,831
Adrian Goldman, EU (Mar 2017), £546,576
Sheena Radford, Wellcome Trust (Mar 2017), £1,836,482
Tom Bennett, Royal Society (Mar 2017), £15,000
Jamie Johnston, Royal Society (Mar 2017), £15,000
Beatrice Filippi, Royal Society (Mar 2017), £15,000
Ryan Seipke, BBSRC (Feb 2017), £52,116
Mary O'Connell, BBSRC (Feb 2017), £46,986
Hannah Dugdale, NERC (Feb 2017), £504,138
Anastasia Zhuravleva, EPSRC (Jan 2017), £100,792
Richard Bayliss, Cancer Research UK (Jan 2017), £1,600,000
John Barr, EU (Jan 2017), £339,000
Mark Harris, Royal Society (Jan 2017), £250,000
Alison Dunn, NERC (Jan 2017), £105,000
Alex Breeze, Pancreatic Cancer Research Fund (Jan 2017), £180,000
Alison Dunn, NERC (Dec 2016), £18,000
Lisa Collins, BBSRC (Dec 2016), £1,681,835
Brendan Davies, Leverhulme Trust (Dec 2016), £247,555
Alan Benson, Mark Drinkhill, Ed White, British Heart Foundaion (Dec 2016), £217,223
Adrian Goldman, Royal Society (Dec 2016), £82,999
Lisa Roberts, Alex Breeze, Brendan Davies, Timothy Devinney, Oliver Harlen, Joseph Holden, Anthea Hucklesby, Pamela Jones, Philip Mellor, RCUK (Nov 2016), £484,172
Lisa Roberts, Alex Breeze, Brendan Davies, Timothy Devinney, Oliver Harlen, Joseph Holden, Anthea Hucklesby, Pamela Jones, Philip Mellor, Wellcome Trust (Nov 2016), £119,343
Katie Field, Rank Prize Funds (Nov 2016), £20,000
Jessica Kwok, Royal Society (Nov 2016), £14,948
John Ladbury, Cancer Research UK (Oct 2016), £4,250