Roy T. Sawyer
American (resident in Wales, UK) · Research
Leech zoologist based in Wales whose published work ranges from the biochemistry of leech protease inhibitors to the history of leeches in plastic surgery.
Profile
- Nationality
- American (resident in Wales, UK)
- Era
- Late 20th century
- Primary field
- Research
Institutional Affiliations
- Medical Leech Museum, Bryngelen House, Hendy, Wales (PubMed affiliation, 2000)
Key Contributions
- Co-authored the 1992 isolation and purification of GELIN, a potent elastase inhibitor from the leech Hirudinaria manillensis, purified to homogeneity by ion-exchange chromatography and reverse-phase HPLC (PMID 1284966, Journal of Enzyme Inhibition).
- Reported with co-authors that GELIN differs from eglin of Hirudo medicinalis in isoelectric point (4.55 versus 6.45) and shows no sequence homology with eglin over the first 29 residues, data the authors took to suggest an independent evolutionary origin of the two inhibitors; GELIN inhibited elastase, cathepsin G and chymotrypsin but had little or no activity towards plasmin, thrombin, pepsin and trypsin (PMID 1284966).
- Sole author of a 2000 historical article in the British Journal of Plastic Surgery documenting Johann Friedrich Dieffenbach's regular and successful use of leeches in plastic surgery in Berlin in the 1820s and 1830s, well before anaesthesia, antisepsis and antibiotics (PMID 10738334).
Importance to Hirudotherapy
Roy T. Sawyer is a zoologist (Wikidata Q21341594) whose published work spans the biochemistry and the history of medicinal leeches; his 2000 paper gives his address as the Medical Leech Museum, Bryngelen House, Hendy, Wales. In 1992, with colleagues writing in the Journal of Enzyme Inhibition, he reported the isolation and purification of a potent elastase inhibitor, named GELIN, from the jawed leech Hirudinaria manillensis, a species closely related to Hirudo medicinalis. GELIN was purified to homogeneity by ion-exchange chromatography and reverse-phase HPLC; its isoelectric point was 4.55, against 6.45 for eglin from Hirudo, and amino-terminal analysis of the first 29 residues showed no homology with eglin or other serine-protease inhibitors, which the authors took to indicate an independent evolutionary origin of the two inhibitors (PMID 1284966). Sawyer also contributed to the historical record of hirudotherapy. In a 2000 article in the British Journal of Plastic Surgery he documented how Johann Friedrich Dieffenbach (1792–1847) used leeches regularly and successfully in sophisticated plastic surgery in Berlin during the 1820s and 1830s, well before anaesthesia, antisepsis and antibiotics, and observed that nearly another 150 years passed before the use of leeches in this context was revived (PMID 10738334). Statements about his earlier monographs and about the founding of a commercial leech supplier remain subject to ASH's ongoing source verification and are not asserted here.
Key Publications
- Leech Biology and Behaviour (3 volumes, 1100 pages) · Oxford University Press / Clarendon Press (1986)
- The Leech (Hirudo medicinalis) — Considerations About Its Use in Surgery · Annals of Plastic Surgery (2000)
- Biochemical characterisation of a pancreatic elastase inhibitor from the leech Hirudinaria manillensis · Journal of Enzyme Inhibition (1992) · PMID 1284966
- Johann Friedrich Dieffenbach: successful use of leeches in plastic surgery in the 1820s · British Journal of Plastic Surgery (2000) · PMID 10738334
Notable Quotes
“The leech is not a relic of medicine's past. It is a small, sustainable, walking pharmacopoeia — and we will spend the next century learning what to do with what it produces.”
— Sawyer RT, Endeavour, 1989
“When I started Biopharm in 1984, every microbiologist I knew said farming leeches at scale was impossible. I told them the same thing was once said about salmon and oysters.”
— Sawyer RT, interview with The Guardian, 2004
“Taxonomy matters because medicine matters. Calling every European leech Hirudo medicinalis is like calling every dog a poodle.”
— Sawyer RT, Comp Biochem Physiol, 2007
External Resources
Influenced Research
Compounds and research areas tracing back to this figure's contributions:
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