MRC National Institute for Medical Research, London
Science for Health
Martin Webb group project:
Development of fluorescent biosensors and other probes
We have developed fluorescent biosensors based on engineered proteins, to probe for various products of the ATPases and GTPase reactions, inorganic phosphate, nucleoside diphosphate and single-stranded DNA. These involve placing particular fluorescent groups at single amino acids on the surface of the protein, such that the fluorophore senses the ligand binding. Biosensors for inorganic phosphate and nucleoside diphosphate are now available commercially for use by the wider scientific community, as well as by biotech companies.
Crystal structure of the phosphate biosensor: a coumarin-labelled phosphate binding protein.
In addition we are synthesising novel fluorophore-labeled purine nucleotides, in collaboration with Dr John Corrie (NIMR) and using them to investigate the mechanisms of several enzymes, particularly the myosin motors. These analogues have a series of lengths of linker attached to the ribose. In this way, the fluorophore can be closer to or further from the surface of the protein, when the nucleotide is bound and so modulate interactions and fluorescence properties.
Selected publications
- Kunzelmann, S and Webb, MR (2009)
A biosensor for fluorescent determination of ADP with high time resolution.
Journal of Biological Chemistry 284, 33130-33138 PubMed abstract - Dillingham, MS; Tibbles, KL; Hunter, JL; Bell, JC; Kowalczykowski, SC and Webb, MR (2008)
A fluorescent single-stranded DNA binding protein as a probe for sensitive, real time assays of helicase activity.
Biophysical Journal 95, 3330-3339 PubMed abstract - Okoh, MP; Hunter, JL; Corrie, JET and Webb, MR (2006)
A biosensor for inorganic phosphate using a rhodamine-labeled phosphate binding protein.
Biochemistry 45, 14764-71 PubMed abstract - Webb, MR; Reid, GP; Munasinghe, VRN and Corrie, JET (2004)
A series of related nucleotide analogues that aids optimization of fluorescence signals in probing the mechanism of P-Loop ATPases, such as actomyosin.
Biochemistry 43, 14463-71 PubMed abstract
Webb group
Recent publications
Research projects
- DNA helicases: mechanism of coupling ATP hydrolysis to DNA translocation
- Myosins: the relationship between ATP hydrolysis and mechanical events
- Development of fluorescent biosensors and other probes
- The role of small G proteins in cell signalling
Expertise/techniques
Webb biography
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