• Mike Merrick's Research

Related links

• AT JIC:
• Molecular Microbiology
• ON THE WEB:
• Microbes in Norwich

Curriculum Vitae

• 1970 BSc, Genetics, University of Birmingham, UK
• 1973 PhD, Genetics, University of Birmingham, UK
• 1973 - 1976 Postdoctoral Fellow, John Innes Centre, UK
• 1976 - 1995 Research Scientist, Nitrogen Fixation Laboratory, University of Sussex, UK
• 1995 - present Project Leader, Dept. of Molecular Microbiology, John Innes Centre, UK
• 2007 - Honorary Professor, University of East Anglia, UK
• 2001 - present Associate Head of Department. John Innes Centre, UK

Mike Merrick

Associate Head of Department

Molecular Microbiology

Contact details

mike.merrick@jic.ac.uk

Research interests

Research in my laboratory is focussed on bacterial nitrogen metabolism and the ways in which bacteria control all aspects of that metabolism in response to the availability of fixed nitrogen.  Bacteria can use a wide range of organic and inorganic sources of nitrogen and they must therefore coordinate both the expression of genes and the activities of proteins required for nitrogen metabolism with the availability of nitrogen sources in their environment and with their intracellular nitrogen status (for reviews see: Merrick and Edwards, 1995; Arcondeguy et al, 2001).  

My major interests are the biology of ammonium transport across cell membranes, and of PII signal transduction proteins. Ammonium transport (Amt) proteins are ubiquitous, being found in eubacteria, archaebacteria, fungi, plants, and lower animals.  Members of the Amt family are also present in higher animals including humans where their homologues are the Rhesus (Rh) proteins. PII proteins control nitrogen metabolism in prokaryotes and in plant plastids. Indeed their evolutionary origin appears to have been to control, by the PII protein GlnK, of ammonium uptake by Amt proteins in bacteria.

We pioneered the use of the Escherichia coli AmtB protein as model system in which to study the mode of action of Amt proteins (Merrick et al., 2006).  Our studies have included mechanistic questions (Javelle et al., 2007; Hub et al., 2010), determination of the X-ray structure of the AmtB-GlnK complex (Conroy et al., 2007) and solution of the first Rh protein structure using a rare bacterial Rh protein from Nitrosomonas europeaea (Lupo et al., 2007). We have also focussed on the mechanisms whereby PII proteins sense cellular N status and control cellular N metabolism (Truan et al., 2010; Radchenko et al., 2010).