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Melvyn Bragg and guests discuss enzymes, the proteins that control the speed of chemical reactions in organisms which would otherwise happen too slowly to keep the organisms alive.

Melvyn Bragg and guests discuss enzymes, the proteins that control the speed of chemical reactions in living organisms. Without enzymes, these reactions would take place too slowly to keep organisms alive: with their actions as catalysts, changes which might otherwise take millions of years can happen hundreds of times a second. Some enzymes break down large molecules into smaller ones, like the ones in human intestines, while others use small molecules to build up larger, complex ones, such as those that make DNA. Enzymes also help keep cell growth under control, by regulating the time for cells to live and their time to die, and provide a way for cells to communicate with each other.


Nigel Richards
Professor of Biological Chemistry at Cardiff University

Sarah Barry
Lecturer in Chemical Biology at King's College London


Jim Naismith
Director of the Research Complex at Harwell
Bishop Wardlaw Professor of Chemical Biology at the University of St Andrews
Professor of Structural Biology at the University of Oxford

Producer: Simon Tillotson.

Available now

43 minutes

Last on

Thu 1 Jun 2017 21:30


Nigel Richards at Cardiff University

Sarah Barry at King's College London

Jim Naismith at St Andrews and Oxford Universities

Enzymes – BBC Bitesize

Enzymes – Chemguide

Enzymes – Encyclopaedia Britannica

Introducing Metabolism – BBC Bitesize

Proteolytic enzymes, past and future – Proceedings of the National Academy of Sciences of the United States of America

Ancient enzyme resurrected from the ancestor of all bacteria – New Scientist

Enzymes – Wikipedia



Jeremy M. Berg, John L. Tymoczko and Lubert Stryer, Biochemistry (W. H. Freeman, 2002)

T. D. H. Bugg, An Introduction to Enzyme and Coenzyme Chemistry (Wiley-Blackwell, 2004)

Jonathan Clark, Understanding the Structure and Function of Enzymes (ebook)

David Dressler and Huntington Potter, Discovering Enzymes (Scientific American Library, 1991)

Brian B. Jacques, Amino Acids & Enzymes: What Are They, Why Do You Need Them (CreateSpace Independent Publishing Platform, 2014)

Steven Rose, The Chemistry of Life (Penguin, 1999)


Role Contributor
Presenter Melvyn Bragg
Interviewed Guest Jim Naismith
Interviewed Guest Sarah Barry
Interviewed Guest Nigel Richards
Producer Simon Tillotson


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