Individual Macromolecule Motion in a Crowded Living Cell

What is it about?

The 'SINGLE-MOLECULE DEMON' (single-molecule ratchet) in IMAGING/MICROSCOPY/SUPER-RESOLUTION MICROSCOPY (NANOSCOPY) and SPECTROSCOPY: Dilute Liquids and Live Cells https://www.growkudos.com/publications/10.2174%252F138920111795470949/reader

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Why is it important?

Zeno Földes-Papp**: The FUNDAMENTAL NATURAL LAWS OF SINGLE-MOLECULE TIME RESOLUTION of freely diffusing molecules. ON THE MOVE TOWARDS NEW HORIZONS. A universal theory on single molecules was drawn upon experimental facts by forming the concept of "THE MEANINGFUL TIME Tm" acting AS FUNDAMENTAL NATURAL LAWS OF SINGLE-MOLECULE TIME RESOLUTION of freely diffusing molecules (i.e. with negligible external forces like a significant hydrodynamic flow or without firm binding or attachment (immobilization) to a solid phase like artificial surfaces and biological menbranes) in dilute liquid and live cells (3D-diffusional normal and anomalous processes as well as in or on artificial or biological membranes as (2D-diffusional normal and anomalous processes). The physical laws correspond to the MATHEMATICAL EQUATIONS which we use to describe every single molecule. This is the Theory of Single-Molecule Biophysics & Biochemistry Based On Individually Diffusing Molecules in Dilute Liquids and Live Cells. It must be made crystal clear that the underlying physics and molecular biochemistry can be modified easily but things hardly get worse when there is any trouble with the mathematics which rules the physical and biological formulations. WE PREVAILED AND YET OTHERS DID NOT. The advantages of the new 'Theory of Single-Molecule Biophysics & Biochemistry Based On Individually Diffusing Molecules in Dilute Liquids and Live Cells' are evident: The 'SINGLE-MOLECULE DEMON' (single-molecule ratchet) in IMAGING/MICROSCOPY/SUPER-RESOLUTION MICROSCOPY (NANOSCOPY) and SPECTROSCOPY: Dilute Liquids and Live Cells •https://www.growkudos.com/publications/10.2174%252F138920111795470949/reader •https://www.linkedin.com/pulse/how-get-high-single-molecule-biophysics-biochemistry-data-zeno?trk=public_profile_article_view Földes-Papp, Z. Single-molecule time resolution: limits and thermodynamic considerations, Researchgate, 2021. The 2021 Földes Papp paper argues that single molecule time resolution is fundamentally limited by stochastic diffusion and thermodynamic jitter, which impose strict constraints on the minimum meaningful measurement time. The citation corresponds to Földes Papp, Z. (2021). Single molecule time resolution in dilute liquids and live cells at the molecular scale: Constraints on the measurement time. American Journal of Translational Medicine, 5(3), 154–165. The ResearchGate PDF linked in the results contains the same article. Core scientific idea: What limits single molecule time resolution? Across the supplied sources, Földes Papp emphasizes that translational diffusion at the molecular scale is inherently stochastic, and this randomness sets a lower bound on how fast meaningful measurements can be made to be sure tha one individual molecule is observed in the measurement withoud immobilization or hydrodynamic focussing, Key points: • Diffusion is not smooth but governed by random thermal fluctuations (“thermodynamic jitter”), which introduce unavoidable timing uncertainty • Because of this, there exists a minimum measurement time below which the observed signal no longer reflects molecular behavior but only stochastic noise. • These limits apply both in dilute liquids and live cellswithout immobilization or hydrodynamic flow. The “Földes Papp limits” The resutls explicitly state that the Földes Papp limits provide the “exact answers” for the achievable time resolution in single molecule experiments without immobilization. These limits arise from: • the stochastic nature of diffusion, • the thermodynamic constraints on positional uncertainty, and • the requirement that measurement time must exceed the characteristic diffusion driven fluctuation time. Thermodynamic considerations The companion paper on thermodynamic signatures clarifies the conceptual basis: • Thermodynamic jitter is a fundamental source of noise, not an experimental artifact.. • Misunderstandings about this jitter can lead to unrealistic expectations about achievable time resolution. • Properly accounting for these thermodynamic effects is essential for designing experiments and interpreting single molecule trajectories-. Why this matters Together, these works establish a thermodynamic and stochastic framework for determining: • how fast one can sample a freely diffusing molecule, • how long an observation must be to extract meaningful biophysical information, about an individual molecule and • how to design experiments that respect these physical limits,. This framework is foundational to Földes Papp’s broader research program on single molecule biophysics based on stochastic diffusion . Summary • The 2021 article defines constraints on measurement time for single molecule experiments. • These constraints arise from stochastic diffusion and thermodynamic jitter. • The “Földes Papp limits” describe the minimum meaningful time resolution achievable without immobilization. • The thermodynamic companion papers deepen the theoretical basis and correct common misconceptions.

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