The main goal of the Small Biosystems Lab is to combine advanced experimental techniques and theoretical knowledge to address questions related to energy processes in the nano-scale. The main research lines are single-molecule biophysics and non-equilibrium physics. The research developed has spanned the study of intermolecular interactions (such as peptides and proteins binding to DNA), intramolecular interactions (DNA hybridization, DNA, RNA and protein folding) and fundamental research in nonequilibrium physics of molecular systems, where Brownian fluctuations rule energy, entropy and information flows. The group has also demonstrated the power of combining nonequilibrium physics theories and single molecule methods to extract ligand-DNA binding free energies and binding sites by mechanically footprinting DNA with unprecedented accuracy. Their research is now moving towards information-work energy conversion and how to define thermodynamic information in nonequilibrium processes under feedback control and mutational molecular ensembles.
Two recent developments will expand future research in the group. First, the optical tweezers with temperature controller that operates in the range 5-40ºC. This permits to measure enthalpy and entropy differences down to the single weak molecular bond accuracy (1kcal/mol) improving the knowledge of nucleic acids thermodynamics. Second, a new line of research based on electrical measurements of single molecule translocation across nanopores (using glass pipette nanochannels) is now available in the lab. The new electrical setup combined with optical tweezers allows for controlled molecular translocation through electrical and force measurements, offering a potentially useful tool for single molecule sequencing.
Fèlix Ritort Farran (Full Professor) ritort(at)ub.edu
Maria Mañosas Castejon (Postdoctoral Researcher Ramon y Cajal)
I. Di Terlizzi*, M. Gironella*, D. Herraez-Aguilar, T. Betz, F. Monroy, M. Baiesi, and F. Ritort. “Variance Sum Rule for Entropy Production”. Science Magazine, 1st March 2024. Doi: 10.1126/science.adh1823
Generalized continuous Maxwell demons. J. P. Garrahan and F. Ritort. Phys. Rev. E 107, 3, 034101. March 2023. Doi: 10.1080/14756366.2022.2158822
N-States Continuous Maxwell Demon. Raux P.; Ritort F. Entropy 2023, 25(2), 321. Doi: 10.3390/e25020321
Molten globule-like transition state of protein barnase measured with calorimetric force spectroscopy. Rico-Pasto M., Zaltron A., Davis S.J., Frutos S., Ritort F. Proceedings of the National Academy of Sciences of the United States of America, 119, 11, e2112382119, 2022
Temperature-dependent elastic properties of DNA. Rico-Pasto M., Ritort F. Biophysical Reports, 2, 3, 100067, 2022
Measurement of the specific and non-specific binding energies of Mg2+ to RNA. Martinez-Monge A., Pastor I., Bustamante C., Manosas M., Ritort F. Biophysical Journal, 121, 16, 3010, 2022
Folding Free Energy Determination of an RNA Three-Way Junction Using Fluctuation Theorems. Aspas-Caceres J., Rico-Pasto M., Pastor I., Ritort F. Entropy, 24, 7, 895, 2022
Force dependence of proteins’ transition state position and the bell–evans model. Rico-Pasto M., Zaltron A., Ritort F. Nanomaterials. 2021, 11, 11
Dissipation Reduction and Information-to-Measurement Conversion in DNA Pulling Experiments with Feedback Protocols. Rico-Pasto M., Schmitt R.K., Ribezzi-Crivellari M., Parrondo J.M.R., Linke H., Johansson J., Ritort F. Physical Review X. 2021, 11, 3, 031052
Cooperativity-Dependent Folding of Single-Stranded DNA. Viader-Godoy X., Pulido C.R., Ibarra B., Manosas M., Ritort F. Physical Review X. 2021, 11, 3, 031037
Sugar-pucker force-induced transition in single-stranded DNA. Viader-Godoy X., Manosas M., Ritort F. International Journal of Molecular Sciences. 2021, 22, 9, 4745
Direct detection of molecular intermediates from first-passage times. Thorneywork A.L., Gladrow J., Qing Y., Rico-Pasto M., Ritort F., Bayley H., Kolomeisky A.B., Keyser U.F. Science Advances. 2020, 6(18)
Detection of single DNA mismatches by force spectroscopy in short DNA hairpins. Landuzzi F., Viader-Godoy X., Cleri F., Pastor I., Ritort F. Journal of Chemical Physics. 2020, 152(7)
Descifrando los mecanismos de motores moleculares que trabajan en el AND. CNS2022-135910. IP: Maria Mañosas Castejon. Ministerio de Ciencia e Innovación (2023-2025)
Energía e información en la nanoescala en materia biológica. PID2022-139913NB-I00. IP: Félix Ritort Ferran. Ministerio de Ciencia e Innovación (2023-2026)
ICREA ACADEMIA 2008, 2013, 2018. IP: Félix Ritort Ferran. Generalitat de Catalunya (2009-2023).
Experimental measurement of entropy and information in single molecules and cells. PID2019-111148GB-I00. Ministerio de Ciencia, Innovación y Universidades. IP: Felix Ritort Ferran/Maria Mañosas Castejon(2020-2023)
PROtein SEQuencing using Optical single molecule real-time detection (PROSEQO). IP: Félix Ritort. European Union (Horizon 2020). 2016-2019
-Optical tweezers instruments (3 at room temperature, 1 with temperature controller), 1 magnetic tweezers, 1 instrumental setup for single molecule translocation also combined with optical tweezers.
Università degli Studi di Padova (Italy); B. Ibarra (IMDEA,Madrid); U. Keyser (U. Cambridge); U. Seifert (U. Stuttgart), P. Pietzonka (U. Cambridge), M. Baiesi and I. Di Terlizzi (U. Padova); A. Alemany (Hubrecht Inst.,Utrecht), J. Johansson and H. Linke (U. Lund), J. M. Parrondo (U. Autonoma Madrid) and M. Ribezzi (ESPCI, Paris), on information-energy conversion; A. Zaltron, G. Mistura, F. Seno (U. Padova), J. Sancho (U. Zaragoza) and S. Frutos (Parc científic, Barcelona) on protein folding; C. V. Bizarro (U. Porto Alegre) on RNA unzipping. G. Wuite (U. Vrije, Amsterdam) on red blood cell dynamics; V. Croquette (ENS, Paris) on helicase dynamics; F. Cleri (U. Lille, France) on simulations of hairpin folding kinetics; A. Crisanti (U. La Sapienza, Roma) and M. Picco (U. Paris VI, Paris) on fluctuation theorems in glassy systems; F. Westerlund (U. Chalmers, Gotheborg) on force spectroscopy of nucleic acids.