Science & Research Projects
Projects currently in development and previous work
The cadherins are a family of molecules involved with cell adhesion. They consist of several (usually 5) extracellular domains, a transmembrane region and an intracellular domain which binds to catenins. Whilst the Ca2+ dependent nature of cadherin-mediated adhesion, and the Trp2 to His-Val-Ala homodimerisation process is well known, there remain several different mechanisms proposed for homodimer-homodimer interaction for cell adhesion.
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We have been using a combination of computational and molecular techniques to investigate the potential mechanism and sites of interaction for cadherin-homodimer-mediated cell adhesion. The image on the right is a rendered view of the EC1 extracellular domain of C-cadherin from Xenopus. The domain was cropped from the pdb 1L3W using Sybyl from Tripos and the image shown here was rendered by pyMol. The EC1 domain contains the well characterised His-Val-Ala binding pocket involved in homodimer formation, along with the key dimerisation residue Trp2. |
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The chlamydiae are obligate intracellular parasites, and are an important group of disease-causing bacteria. C. trachomatis is responsible for both genito-urinary infection and occular (trachoma) infection in humans and is one of the most significantly increasing sexually transmitted infections worldwide.
As part of my PhD studies, I investigated the use of the C. trachomatis incA protein as a potential marker for infection and target for a diagnostic test. This work was also a 'proof of concept' for the Antigen Finder algorithm (below). The work has continued beyond my PhD work with the help of an MSc student this year, and further investigation has been done using our new confocal microscope.
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The image on the left shows the results of an immunocytochemistry performed on a culture of C. trachomatis-infected McCoy fibroblasts. Cell nuclei are counterstained blue with hemotoxylin and chlamydial inclusion bodies appear brown from HRP-mediated DAB oxidation. The primary antibody was produced after application of the Antigen Finder algorithm (below) to the chlamydial incA protein. If you are interested in the chlamydiae, then visit the excellent on-line resource: www.chlamydiae.com which covers everything you would ever need to know! |
Cranfield Health recently acquired a shiney new Zeiss laser scanning confocal microscope. I have been using this to extend some of my previous chlamydia work, and to improve on some of the more established techniques in our lab. At the moment the new protocols are very much a work in progress!
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The two images on the left show human chromosomes at metaphase, spread on a slide and stained with a Sytox green fluorophore. The image on the far left also includes a complete nucleus with clearly condensed chromatin - probably late prophase Obtaining successful metaphase spreads is the first step towards developing a robust Fluorescent In Situ Hybridisation (FISH) protocol for the lab. |
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The image shown on the right is Confocal microscope image of a Chlamydia trachomatis-infected McCoy cell. The cell nucleus is stained with a Sytox Green fluorophore and the intracellular chlamydia inclusion body is detected with a specific antibody labelled with an Alexa-Fluor 555 conjugate. |
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