History and present activities

The Hof Fluorescence Group is a part of the Biophysical Chemistry Department at the Heyrovsky Institute of the  Czech Academy of Sciences (CAS). The main research interest is focused on the development of new fluorescence methods and their application in the research of structure, functionality and dynamics of biomembranes and proteins on the picosecond to millisecond time scale. Moreover, advanced in vivo fluorescence microscopy and recently also label-free imaging (i.e. Optical Near-Field Electron Microscopy (ONEM)) lie in the interest.

The group succeeded to develop  several novel fluorescence techniques including the method of time dependent fluorescence shift (TDFS), z-scan Fluorescence Correlation Spectroscopy (z-FCS), Fluorescence Lifetime Correlation Spectroscopy (FLCS), Fluorescence Spectral Correlation Spectroscopy (FSCS), Dynamic Saturation Optical Microscopy (DSOM) and Förster resonance Energy Transfer analyzed by Monte-Carlo simulations (MC-FRET) for quantitative size determination of nanodomains. 

Moreover, the group implemented cutting edge fluorescence microscopic techniques like   photoactivation localization microscopy (PALM), superresolution optical fluctuation imaging (SOFI), single particle tracking (SPT), and imaging FCS (imFCS). 

Applications of those techniques are connected with current grant projects, are:

  • Membrane biophysics at the atomistic level
  • Nanoscale membrane organization and its relationship to protein function
  • Structural and dynamic analysis of cellular nanostructures involved in human immune responses to pathogens
  • Intracellular trafficking in the context of neurodegeneration, with a focus on lipid droplets and vesicular transport
  • Innovative microscopy approaches, including Optical Near-Field Electron Microscopy (ONEM) in combination with Graphene-Induced Energy Transfer (GIET)

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The group started in 2000 supported by a start-up investment of a Zeiss Confocor 1 FCS Microscope.

  • In 2001 the lab was extended by additional rooms and equipment (TCSPC and steady state fluorimeters (IBH, Horiba JY).
  • In 2004 the confocal microscope was extended for Fluorescence Lifetime Correlation Spectroscopy. The growth of the laboratory was heavily supported by the home institute as well as by the Czech Science Foundation.
  • In 2005 the Academy of Sciences financed the built up of a Time Resolved Single Molecule Sensitive Confocal Fluorescence Microscope (PicoQuant, Olympus) and the group became part of the newly founded Department of Biophysical Chemistry.
  • In 2006 Martin Hof became the coordinator of the National Research Centre "Advanced Fluorescence Microscopy in Biological and Medical Sciences" that was financed by the Ministry of Education. Part of if the resources were use for combining the expanding the above mentiones microscope by a galvanosanner and building a second  confocal TCSPC microscope
  • In 2011 Martin Hof was awarded by the PRAEMIUM ACADEMIAE by the Academy of Sciences of the Czech Republic. Thanks to that generous award, two wide-field microscopes enabling photo-activated localization microscopy (PALM), superresolution optical fluctuation imaging (SOFI), and single particle tracking (SPT) were built. Morever, a Titan Sapphir Laser for two-photon excitation was purchased
  • In 2018 Martin Hof successfully applied for the EXPRO project supporting the excellence in science, which has further accelerated the group research mainly in the field of protein production.
  • In 2020 the group became member of a consortium (together with Unicersities Leiden and Vienna) developing including Optical Near-Field Electron Microscopy (ONEM), funded by the FET-OPEN EC Horizon initiative. 

The group has published more than 250 scientfic papers within the last 25 years. Prof. Hof selected following 25 papers as milestones:

  1. Svobodová, B (Svobodova, Barbora) [1] , [2] ; St'astny, D (St'astny, David) [1] , [3] ; Blom, H (Blom, Hans) [4] ; Mikhalyov, I (Mikhalyov, Ilya) [5] ; Gretskaya, N (Gretskaya, Natalia) [5] ; Balleková, A (Ballekova, Alena) [1] ; Sezgin, E (Sezgin, Erdinc) [6] ; Hof, M (Hof, Martin) [1] ; Sachl, R (Sachl, Radek) [1] Revised Diffusion Law Permits Quantitative Nanoscale Characterization of Membrane OrganizationAnal Chem DOI10.1021/acs.analchem.5c00021

  2. Scollo, F (Scollo, Federica) [1] ; Kulig, W (Kulig, Waldemar) [3] ; Nicita, G (Nicita, Gabriele) [2] ; Ludwig, AK (Ludwig, Anna-Kristin) [4] ; Ricardo, JC (Ricardo, Joana C.) [1] ; Zito, V (Zito, Valeria) [5] ; Kapusta, P (Kapusta, Peter) [1] ; Vattulainen, I (Vattulainen, Ilpo) [3] ; Cebecauer, M (Cebecauer, Marek) [1] ; Gabius, HJ (Gabius, Hans-Joachim) [4] ; Kaltner, H (Kaltner, Herbert) [4] ; Maccarrone, G (Maccarrone, Giuseppe) [2] ; Hof, M (Hof, Martin) [1] Unraveling the GM1 Specificity of Galectin-1 Binding to Lipid Membranes  ACS BIO & MED CHEM AU DOI10.1021/acsbiomedchemau.5c00040

  3. Javanainen, M. - Šimek, Jan - Tranter, D. - O'Keefe, S. - Karki, S. - Biriukov, D. - Šachl, Radek - Paavilainen, V. O. Lipid Scrambling Pathways in the Sec61 Translocon Complex. Journal of the American Chemical Society. Roč. 147, č. 19 (2025), s. 15970-15984.

  4. Scollo, Federica - Tempra, Carmelo - Evci, Huseyin - Riopedre Fernández, Miguel - Olžyńska, Agnieszka - Javanainen, Matti - Uday, Arunima - Cebecauer, Marek - Cwiklik, Lukasz - Martinez-Seara, Hector - Jungwirth, Pavel - Jurkiewicz, Piotr - Hof, Martin Can calmodulin bind to lipids of the cytosolic leaflet of plasma membranes? Open Biology. Roč. 14, č. 9 (2024), č. článku 240067.

  5. Davidović, David - Kukulka, M. - Sarmento, M. J. - Mikhalyov, I. - Gretskaya, N. - Chmelová, Barbora - Ricardo, Joana Catarina - Hof, Martin - Cwiklik, Lukasz - Šachl, Radek Which Moiety Drives Gangliosides to Form Nanodomains? Journal of Physical Chemistry Letters. Vol. 14, no. 25 (2023), p. 5791-5797

  6. Singh, Vandana - Macharová, Sabína - Riegerová, Petra - Steringer, J. P. - Mueller, H. - Lolicato, F. - Nickel, W. - Hof, Martin - Šachl, Radek Determining the Functional Oligomeric State of Membrane- Associated Protein Oligomers Forming Membrane Pores on Giant Lipid Vesicles. Analytical Chemistry. Roč. 95, č. 23 (2023), s. 8807-8815.

  7. Franke, Christian; Chum, Tomas; Kvicalova, Zuzana; Glatzova, Daniela; Gentsch, Gregor Joerg; Rodriguez, Alvaro; Helmerich, Dominic A.; Herdly, Lucas; Mavila, Harsha; Frank, Otakar; Brdicka, Tomas; van de Linde, Sebastian and Cebecauer, Marek. Approach to map nanotopography of cell surface receptors. Comms Biol. 5: 218 (2022); DOI: 10.1038/s42003-022-03152-y

  8. Vinklárek, I. S.; Vel'as, L.; Riegerová, P.; Skála, K. ; Mikhalyov, I.; Gretskaya, N.; Hof, M.; Šachl, R. Experimental Evidence of the Existence of Interleaflet Coupled Nanodomains: An MC-FRET Study. Journal of Physical Chemistry Letters. Vol. 10, no. 9 (2019), p. 2024-2030.

  9. Kokkonen, P.; Sýkora, J.; Prokop, Z.; Ghose, A.; Bednář, D.; Amaro, M.; Beerens, K.; Bidmanová, Š.; Slánská, M.; Březovský, J.; Damborský, J.; Hof, M. Molecular Gating of an Engineered Enzyme Captured in Real Time. Journal of the American Chemical Society. Vol. 140, no. 51 (2018), p. 17999-18008. 

  10. Lukes, Tomas; Glatzova, Daniela; Kvicalova, Zuzana; Levet, Florian; Benda, Ales; Letschert, Sebastian; Sauer, Markus; Brdicka, Tomas; Lasser, Theo and Cebecauer, Marek. Quantifying protein densities on cell membranes using super-resolution optical fluctuation imaging. Nat Commun. 8:1731 (2017). DOI: 10.1038/s41467-017-01857

  11. Melcrová, A.; Pokorná, Š.; Pullanchery, S.; Kohagen, M.; Jurkiewicz, P.; Hof, M.; Jungwirth, P.; Cremer, P. S.; Cwiklik, L. The complex nature of calcium cation interactions with phospholipid bilayers. Scientific Reports. Vol. 6, DEC 2016 (2016).

  12. Amaro, M.; Šachl, R.; Aydogan, G.; Mikhalyov, I.; Vácha, R.; Hof, M. GM1 Ganglioside Inhibits β-Amyloid Oligomerization Induced by Sphingomyelin. Angewandte Chemie: International edition. Vol. 55, no. 32 (2016), p. 9411-9415 ISSN 1521-3773.

  13. Amaro M.; Brezovský J.; Kováčová S.; Sýkora J.; Bednář D.; Němec V.; Lišková V.; Kurumbang NP; Beerens K.; Chaloupková R.; Paruch K.; Hof M.; Damborský J. Site-specific analysis of protein hydration based on unnatural amino Acid fluorescence., J. Am. Chem. Soc., 2015, 137(15):4988-92. 

  14. Sýkora, J.; Brezovský, J.; Koudeláková, T.; Lahoda, M.; Fořtová, A.; Chernovets, T.; Chaloupková, R.; Štěpánková, V.; Prokop, Z.; Smatanová, I.K.; Hof, M.; Damborský, J. Dynamics and hydration explain failed functional transformation in dehalogenase design.  Nat. Chem. Biol. Vol. 10, no. 6 (2014), p. 428-430. 

  15. Benda, A.; Kapusta, P.; Hof, M.; Gaus, K. Fluorescence spectral correlation spectroscopy (FSCS) for probes with highly overlapping emission spectra, 2014, Opt. Express, 22, 3, 2973-2988.

  16. Jurkiewicz, P.; Cwiklik, L.; Vojtíšková, A.; Jungwirth, P.; Hof, M. Structure, Dynamics, and Hydration of POPC/POPS Bilayers Suspended in NaCl, KCl, and CsCl Solutions, 2012, BBA - Biomembranes 1818, 3, 609-616. 

  17. Šachl, R.; Humpolíčková; J.; Štefl, M.; Johansson, L.B.-Å.; Hof, M. Limitations of Electronic Energy Transfer in Lipid Nanodomain Size Estimation, 2011, Biophys. J., 101, L60-L62.

  18. Beranová, L.; Cwiklik, L.; Jurkiewicz, P.; Hof, M.; Jungwirth, P. Oxidation Changes Physical Properties of Phospholipid Bilayers: Fluorescence Spectroscopy and Molecular Simulations, 2010, Langmuir 26, 61406144.

  19. Jesenská, A. - Sýkora, Jan - Olžyńska, Agnieszka - Brezovský, J. - Zdráhal, Z. - Damborský, J. - Hof, Martin Nanosecond Time-Dependent Stokes Shift at the Tunnel Mouth of Haloalkane Dehalogenases. Journal of the American Chemical Society. Roč. 131, č. 2 (2009), s. 494-501.

  20. Humpolíčková, Jana - Benda, Aleš - Sýkora, Jan - Macháň, Radek - Kral, Teresa - Gasinska, B. - Enderlain, J. - Hof, Martin Equilibrium dynamics of spermine-induced plasmid DNA condensation revealed by fluorescence lifetime correlation spectroscopy. Biophysical Journal. Roč. 94, č. 3 (2008), L17-L19.

  21. Jurkiewicz, P., A. Olżyńska, M. Langner, M. Hof Headgroup Hydration and Mobility of DOTAP/DOPC Bilayers: A Fluorescence Solvent Relaxation Study (2006) Langmuir, 22, 8741 8749.

  22. Magdalena Przybylo, Jan Sýkora, Jana Humpolíčková, Aleš Benda, Anna Zan, Martin Hof „The lipid diffusion in giant unilamellar vesicles is more than two times faster than in supported phospholipid bilayers under identical conditions“ (2006) Langmuir 22: 9096-9099

  23. Aleš Benda, Veronika Faguľová, Alexander Deyneka, Joerg Enderlein and Martin Hof „Fluorescence Lifetime Correlation Spectroscopy Combined with Lifetime Tuning: New Perspectives in Supported Phospholipid Bilayer Research“ (2006), Langmuir 22: 9580-9585

  24. A.Benda, M.Beneš, V. Mareček, A.Lhotský, W.Th.Hermens & M.Hof “How to Determine Diffusion Coefficients in Planar Phospholipid Systems by Confocal Fluorescence Correlation Spectroscopy” (2003), Langmuir, 19, 4120-4126.

  25. J. Sýkora, P. Kapusta, V. Fidler, & M. Hof `On What Time-Scale Does Solvent Relaxation in Phospholipid Bilayers Happen?' (2002), Langmuir, 18(3), 571-574.