Browse/search for people

Publication - Professor Christiane Berger-Schaffitzel

    Membrane protein insertion and proton-motive-force-dependent secretion through the bacterial holo-translocon SecYEG-SecDF-YajC-YidC


    Schulze, RJ, Komar, J, Botte, M, Allen, WJ, Whitehouse, S, Gold, VAM, Nijeholtb, JALA, Huard, K, Berger, I, Schaffitzel, C & Collinson, I, 2014, ‘Membrane protein insertion and proton-motive-force-dependent secretion through the bacterial holo-translocon SecYEG-SecDF-YajC-YidC’. Proceedings of the National Academy of Sciences of the United States of America, vol 111., pp. 4844-4849


    The SecY/61 complex forms the protein-channel component of the ubiquitous protein secretion and membrane protein insertion apparatus. The bacterial version SecYEG interacts with the highly conserved YidC and SecDF-YajC subcomplex, which facilitates translocation into and across the membrane. Together, they form the holo-translocon (HTL), which we have successfully over-expressed and purified. In contrast to the homo-dimeric SecYEG, the HTL is a hetero-dimer composed of single copies of SecYEG and SecDF-YajC-YidC. The activities of the HTL differ from the archetypal SecYEG complex. It is more effective in cotranslational insertion of membrane proteins and the posttranslational secretion of a beta-barreled outer-membrane protein driven by SecA and ATP becomes much more dependent on the proton-motive force. The activity of the translocating copy of SecYEG may therefore be modulated by association with different accessory subcomplexes: SecYEG (forming SecYEG dimers) or SecDF-YajC-YidC (forming the HTL). This versatility may provide a means to refine the secretion and insertion capabilities according to the substrate. A similar modularity may also be exploited for the translocation or insertion of a wide range of substrates across and into the endoplasmic reticular and mitochondrial membranes of eukaryotes.

    Full details in the University publications repository