Gabriele Butkute, events and administrative assistant at the Society of Biology, writes about Sir David Hopwood, a scientist featured in the Biology: Changing the World top ten poll.
Professor Sir David Hopwood, a British geneticist and microbiologist, carried out fundamental research into the genetics of the soil bacteria Streptomyces, an organism which gives rise to half the world’s antibiotics in use today.
Ever since the discovery of penicillin in 1928, antibiotics have been one of the most widely used groups of drugs, and this has led to increasing antibiotic resistance.
After graduating in botany from St John’s College, Cambridge in 1954, Hopwood chose to do a PhD in the Botany School at Cambridge in the field of microbial genetics, focusing on a group of soil bacteria called Streptomyces.
This group of bacteria were known to be a very promising source of antibiotics as they had already been shown to secrete a number of products, such as streptomycin and tetracycline, as a part of their metabolism. Such products can act as signalling molecules, stimulate or inhibit enzyme function or be a part of bacteria defence mechanism. In order to defend themselves from other bacteria and reduce competition for habitat and food, Streptomyces produce antibiotics.
During the course of his PhD, Hopwood demonstrated that Streptomyces can exchange genetic information between bacterial cells. Hopwood carried on the work at the University of Glasgow and later at the John Innes Centre in Norwich, and found out how the genes, responsible for the production of antibiotics, are arranged.
His research group was the first to show that antibiotic genes are clustered, which means that when genetic material is being transferred between bacteria, those genes are likely to be transferred together. Later he initiated the sequencing of the clusters, only to find out that not all of them are ‘switched on’ all the time – Streptomyces contain many additional gene clusters that don’t create a product under standard laboratory conditions.
This discovery was the first step into what is now known as ‘designer antibiotics’ – genetically engineering bacteria to produce new antibiotics. Hopwood was the first to produce a hybrid antibiotic by genetic manipulation of different Streptomyces bacteria in 1985. Such an extraordinary achievement plays a big and promising role in creating new antibiotics and this way battling resistance to the existing ones.
In 2001 he co-ordinated the sequencing of Streptomyces coelicolor at the Sanger Institute, which was the largest sequenced genome at the time.
Hopwood has been an Emeritus Fellow in the Department of Molecular Microbiology at the John Innes Centre since his formal retirement in 1998, and continues to actively participate in the field of novel antibiotic discovery using genetic manipulation by editing, writing commentaries, contributing to symposia and organising a biennial series of summer schools in Croatia.
Biology: Changing the World is a heritage project of the Society, supported by the Heritage Lottery Fund and in partnership with the Biotechnology and Biological Sciences Research Council.