title: Single Particle Plasmon Sensors as Label-Free Technique To Monitor MinDE Protein Wave Propagation on Membranes.
abstract: We use individual gold nanorods as pointlike detectors for the intrinsic dynamics of an oscillating biological system. We chose the pattern forming MinDE protein system from Escherichia coli (E. coli), a prominent example for self-organized chemical oscillations of membrane-associated proteins that are involved in the bacterial cell division process. Similar to surface plasmon resonance (SPR), the gold nanorods report changes in their protein surface coverage without the need for fluorescence labeling, a technique we refer to as NanoSPR. Comparing the dynamics for fluorescence labeled and unlabeled proteins, we find a reduction of the oscillation period by about 20%. The absence of photobleaching allows us to investigate Min proteins attaching and detaching from lipid coated gold nanorods with an unprecedented bandwidth of 100 ms time resolution and 1 h observation time. The long observation reveals small changes of the oscillation period over time. Averaging many cycles yields the precise wave profile that exhibits the four phases suggested in previous reports. Unexpected from previous fluorescence-based studies, we found an immobile static protein layer not dissociating during the oscillation cycle. Hence, NanoSPR is an attractive label-free real-time technique for the local investigation of molecular dynamics with high observation bandwidth. It gives access to systems, which cannot be fluorescently labeled, and resolves local dynamics that would average out over the sensor area used in conventional SPR.
authors.affiliation: Institute of Physical Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Lambertz
authors.affiliation: Department of Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry , Am Klopferspitz 18, D-82152 Martinsried, Germany.
authors.forename: Ariadna
authors.initials: A
authors.lastname: Martos
authors.affiliation: Institute of Physical Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Henkel
authors.affiliation: Institute of Physical Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Neiser
authors.affiliation: Institute of Physical Chemistry, University of Goettingen , Tammannstrasse 6, D-37077 Goettingen, Germany.
authors.forename: Torben-Tobias
authors.initials: TT
authors.lastname: Kliesch
authors.affiliation: Institute of Physical Chemistry, University of Goettingen , Tammannstrasse 6, D-37077 Goettingen, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Janshoff
authors.affiliation: Department of Cellular and Molecular Biophysics, Max Planck Institute of Biochemistry , Am Klopferspitz 18, D-82152 Martinsried, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Schwille
authors.affiliation: Institute of Physical Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Sönnichsen
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D018797:Cell Cycle Proteins / Q000737:chemistry*; D004926:Escherichia coli; D029968:Escherichia coli Proteins / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D006046:Gold / Q000097:blood / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods
chemical_list: D018797:Cell Cycle Proteins; D029968:Escherichia coli Proteins; D005456:Fluorescent Dyes; D008051:Lipid Bilayers; C093548:MinE protein, E coli; D006046:Gold; D000251:Adenosine Triphosphatases; C072069:MinD protein, E coli
keywords: Min system; Optical dark-field spectroscopy; gold nanorod; plasmon sensor; protein coverage; spatiotemporal dynamics