The Collinson Lab explore the molecular mechanisms underlying protein translocation across biological membranes for the purposes of transport across (protein secretion and mitochondrial import) and into phospholipid bilayers (membrane protein insertion).

The group studies the ubiquitous Sec machinery using the tractable model organism E. coli by a comprehensive characterisation of function and structure. The structure of the core-SecY translocon responsible for secretion, both alone and in complex with a pre-protein mimic, has been determined in collaboration with Profs Tom Rapoport and Werner Kühlbrandt. Current efforts explore how the free energy available from ATP hydrolysis and the trans-membrane proton motive force (PMF) produce the drive responsible for protein passage into and across the membrane.

Recent developments have identified and produced the holo-translocon capable of both secretion and membrane insertion. New projects exploit the availability of this complex towards the understanding of the cellular mechanisms for membrane protein insertion by a wide ranging analysis of its structure and function (collaboration with recent School of Biochemistry, Bristol appointments: Profs Christiane Schaffitzel and Imre Berger).

A Wellcome Trust Senior Investigator Award has just been initiated in order to utilise the methods and expertise employed for the bacterial translocation system to the much more complex (and interesting!) process governing mitochondrial protein import, membrane protein insertion, folding and assembly.