Protein targeting, translocation and insertion in Escherichia coli: Proteomic analysis of substrate-pathway relationships
2007 (English)Doctoral thesis, comprehensive summary (Other academic)
Approximately 10% of the open reading frames in the genome of the Gram-negative bacterium E. coli encodes secretory proteins, and 20% encodes integral inner membrane proteins (IMPs). These proteins are sorted to their correct cellular compartments (the periplasm and the outer and inner membranes) by specialized targeting and translocation/insertion systems. So far, a very limited set of model proteins have been used to study proteins sorting requirements in E. coli. The main objective of all the papers presented in this thesis was to determine the targeting and translocation/insertion requirements of more E. coli proteins. In papers I and II, this was done using focused approaches. Selected model proteins (lipoproteins and putative outer membrane proteins) were expressed from plasmids and their targeting and translocation were analysed in vitro by crosslinking experiments and/or in vivo by pulse-chase analysis in different E. coli mutant strains. In papers III a comparative sub-proteome analysis was carried out to define the role of the cytoplasmic chaperone SecB in protein targeting. In paper IV, a similar approach was used to study how protein translocation and insertion is affected upon depletion of the essential Sec-translocon component SecE. The ‘global’ approach used in paper III and IV allowed us to study protein targeting and translocation/insertion requirements on a proteome level. This led to the identification of several novel SecB substrates and a large number of potential Sec-translocon independent IMPs.
Place, publisher, year, edition, pages
Stockholm: Institutionen för biokemi och biofysik , 2007. , 132 p.
protein biogenesis, targeting, translocation, insertion, SecB, SecE, E. coli
Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
Research subject Biochemistry
IdentifiersURN: urn:nbn:se:su:diva-6990ISBN: 978-91-7155-481-9OAI: oai:DiVA.org:su-6990DiVA: diva2:197421
2007-09-07, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 12 A, Stockholm, 10:00 (English)
van Dijl, Jan-Maarten, Prof.
de Gier, Jan-Willem, Doc.
List of papers