The scientists created images of the 3D molecular structures of two peptides, including one from snake venom, that inhibit angiotensin-I converting enzyme (ACE), a key protein that regulates blood pressure.
ACE inhibitors, such as the drug Captopril, are taken by millions of people in the UK to treat high blood pressure (hypertension) and heart disease. However the drugs cause side effects such as a persistent cough and angioedema (swelling of the face and throat).
In this Medical Research Council funded study, the team produced images of a snake venom peptide BPPb binding to ACE. Although this peptide has been identified previously as a possible template for drug design, it is the first time scientists have been able to see at the molecular level how the peptide binds to ACE and blocks its action.
Professor Ravi Acharya said: "We found that the BPPb peptide binds to a major portion of the active site of the ACE molecule pushing out a zinc atom which is essential for its correct functioning.
"This is the first time we've observed zinc-independent inhibition of ACE, and so these findings highlight a very exciting opportunity to design new antihypertensive drugs based on this peptide."
In addition, the researchers looked at the structure of angiotensin-II (Ang-II) bound to ACE. Ang-II is a hormone produced by ACE that also inhibits it, creating a feedback loop that stops levels of Ang-II getting too high.
Professor Acharya commented: "We already knew that Ang-II blocks ACE, but not how it does this at the molecular level. This study has shown for the first time how ACE self-regulates by producing a molecule that obstructs its active site when the concentration reaches a certain level."
The next step is to use this structural knowledge as a basis for accelerating the on-going work carried out by Professor Acharya and his collaborators on the development of next generation ACE inhibitors that have improved efficacy and fewer side effects.
The scientists will first use computers to predict the action of different drug designs, then take the best drug candidates and test them in vitro, followed by tests in animal models for hypertension.
Dave Westhead and colleagues in Experimental Haematology, Cancer Research UK (Jan 2015), £700,521
Sheena Radford, Mark Harris, Peter Stockley, Alan Berry, Alex O'Neill, Thomas Edwards, Adrian Goldman, Anastasia Zhuravleva, Wellcome Trust (Jan 2015), £443,015
Bill Kunin, EU (Jan 2015), £157,490
John Colyer, Leeds Teaching Hospitals Charitable Fund (Jan 2015), £40,000
Chris Hassall, Royal Society (Dec 2014), £14,500
Ryan Seipke, Royal Society (Nov 2014), £13,700
Alan Berry, Wellcome Trust (Oct 2014), £749,865
Ian Hope, Marie-Anne Shaw, BBSRC (Oct 2014), £396,565
Alison Ashcroft, Peter Stckley, Sheena Radford, Nic Stonehouse, David Brockwell, Darren Tomlinson, BBSRC (Oct 2014), £340,937
Les Firbank, Joe Holden, BBSRC (Oct 2014), £210,302
Darren Tomlinson and colleagues in Chemistry and Pathology, anatomy and Tumour Biology, Dr Hadwen Trusy (Oct 2014), £194,475
Paul Knox, EU (Oct 2014), £167,229
Martin Stacey and colleagues in Medicine & Health, Pfizer (Oct 2014), £90,453
Darren Tomlinson and colleagues in Experimental Oncology, YCR (Oct 2014), £69,480
Andrew Macdonald, Jamel Mankouri, Kidney Research Fund UK (Oct 2014), £58,878
Mike McPherson and colleagues in Dentistry and Engineering, Wellcome Trust (Oct 2014), £58,437
Dave Westhead and colleagues in Experimental Haemotology, Leukaemia & Lymphoma Research (Sep 2014), £281,424
Emmanuel Paci and colleagues in Chemistry, BBSRC (Sep 2014), £636,759
Andrew Peel, BBSRC (Sep 2014), £371,598
Lars Jeuken, Stephen Evans, BBSRC (Sep 2014), £333,684
Lars Jeuken, BBSRC (Sep 2014), £313,463
Michelle Peckham, Mark Harris, Rao Sivaprasadarao, Eileen Ingham, Nic Stonehouse, Nikita Gamper, Wellcome Trust (Sep 2014), £192,763
Neil Ranson, BBSRC (Aug 2014), £355,253
Stuart Egginton, BHF (Aug 2014), £271,094
Darren Tomlinson, Mike McPherson, Technology Strategy Board (Aug 2014), £98,665
Peter Henderson, Leverhulme Trust (Aug 2014), £15,222
Mike McPherson (and colleagues in the School of Chemistry), EPSRC (Jul 2014), £819,880
Peter Stockley, Neil Ranson, BBSRC (Jul 2014), £455,787
Sheena Radford, Univesity of Michigan (Jul 2014), £138,452
Ryan Seipke, British Society Antimicrobial Chemistry (Jun 2014), £11,960
John Trinick, BHF (Jun 2014), £222,614
Chris West, Leverhulme Trust (Jun 2014), £181,241
Jon Lippiat, Darren Tomlinson, BBSRC (May 2014), £125,174
Christine Foyer, Royal Society (May 2014), £24,000