Dr Phillip Aldridge
Senior Lecturer
- Email: p.d.aldridge@ncl.ac.uk
- Telephone: +44 191 222 7704 or 6242
- Fax: +44 191 222 7424
- Address: Institute for Cell and Molecular Biosciences
Medical School
Newcastle University
Framlington Place
Newcastle upon Tyne
NE2 4HH
Research Interests
Flagellar assembly is a temporal process that begins at the base of the structure in the bacterial membrane. Incorporation of flagellar subunits into the growing structure is facilitated by secretion through the base of the flagellum by an associated secretion apparatus. The temporal regulation of flagellar assembly requires a complex regulatory network that couples expression of the structural subunits to the assembly process. On comparison of the regulatory networks required for flagellar assembly from different bacteria many similarities and differences are apparent.
A group of proteins involved in regulating flagellar assembly in the pathogen Salmonella enterica acts as both secretion chaperones and can influence gene expression. These proteins can be envisioned as molecular foremen at the construction site of a given flagellar structure. There is strong evidence to suggest that all proteins that are secreted through the flagellar associated secretion apparatus require a secretion chaperone. This suggests that all flagellated bacteria would possess secretion chaperones that are required for efficient flagellar assembly. We are using the regulation of gene expression during flagellar assembly as a model system to answer fundamental biological questions relevant to current medical issues regarding microbial infections.
Current Work
We are employing a cross-disciplinary approach to our research combining bacterial genetics, protein biochemistry and structural biology. Our goals include:
1) Characterisation of the molecular activities of the secretion chaperones involved in the regulation of flagellar assembly in S. enterica
2) Identification of flagellar associated secretion chaperones in Caulobacter crescentus.
Secretion substrate recognition and its regulation is an important aspect of protein secretion in all organisms. How the flagellar associated secretion apparatus achieves secretion substrate recognition is still poorly understood. Our cross disciplinary approach will lead to a comprehensive understanding of the regulation of this fundamental aspect of protein secretion.
Selected Publications
- B. E. Scharf;P. D. Aldridge;J. R. Kirby;B. R. Crane. Upward mobility and alternative lifestyles: a report from the 10th biennial meeting on Bacterial Locomotion and Signal Transduction. Mol Microbiol 2009.
- S. Saini;J. D. Brown;P. D. Aldridge;C. V. Rao. FliZ is a post-translational activator of FlhD4C2-dependent flagellar gene expression. J Bacteriol 2008.
- P. Aldridge;J. E. Karlinsey;E. Becker;F. F. Chevance;K. T. Hughes. Flk prevents premature secretion of the anti-σ factor FlgM into the periplasm. Molecular Microbiology 2006, 60(3), 630-642.
- Aldridge, P.D.; Wu, C.; Gnerer, J.; Karlinsey, J.E.; Hughes, K.T.; and Sachs, M.S. Regulatory protein that inhibits both synthesis and use of the target protein controls flagellar phase variation in Salmonella enterica. Proceedings of the National Academy of Sciences of the United States of America 2006, 103(30), 11340-11345.
- Aldridge, P.; Karlinsey, J.E.; Aldridge, C.; Birchall, C.M.; Thompson, D.; Yagasaki, J.; and Hughes, K.T. The flagellar-specific transcription factor, σ28, is the type III secretion chaperone for the flagellar-specific anti-σ28 factor, FlgM. Genes and Development 2006, 20(16), 2315-2326.
- P. Aldridge;J. Gnerer;J. Karlinsey;K. T. Hughes. Transcriptional and translational control of the Salmonella fliC gene. J Bacteriol 2006, 188, 4487-4496.
Funding
Nuffield Foundation: Awards to Newly Appointed Lecturers in Science, Engineering and Mathematics. March 2004 - 2006
Royal Society: Conference Grant. March 2005
BBSRC Research Grant Aug 2006 to 2009
Qualifications
BSc. - Leicester 1993
PhD. - Leicester and Heidelberg (Germany) 1998
Previous Positions
1996 to 2000 Division of Mol. Microbiology, Biozentrum, University of Basel, Basel, Switerland
2000 to 2003 Dept. of Microbiology, University of Washington, Seattle, WA, USA
Memberships
Society for General Microbiology
Society for Applied Microbiology
