Quantifying protein diffusion and capture on filaments.

Biophys J

Arnold Sommerfeld Center for Theoretical Physics and Center for NanoScience, Department of Physics, Ludwig-Maximilians-Universität München, Munich, Germany; Nanosystems Initiative Munich, Ludwig-Maximilians-Universität München, Munich, Germany. Electronic address:

Published: February 2015

The functional relevance of regulating proteins is often limited to specific binding sites such as the ends of microtubules or actin-filaments. A localization of proteins on these functional sites is of great importance. We present a quantitative theory for a diffusion and capture process, where proteins diffuse on a filament and stop diffusing when reaching the filament's end. It is found that end-association after one-dimensional diffusion is the main source for tip-localization of such proteins. As a consequence, diffusion and capture is highly efficient in enhancing the reaction velocity of enzymatic reactions, where proteins and filament ends are to each other as enzyme and substrate. We show that the reaction velocity can effectively be described within a Michaelis-Menten framework. Together, one-dimensional diffusion and capture beats the (three-dimensional) Smoluchowski diffusion limit for the rate of protein association to filament ends.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4336373PMC
http://dx.doi.org/10.1016/j.bpj.2014.12.053DOI Listing

Publication Analysis

Top Keywords

diffusion capture
16
one-dimensional diffusion
8
reaction velocity
8
filament ends
8
diffusion
6
proteins
5
quantifying protein
4
protein diffusion
4
capture
4
capture filaments
4

Similar Publications

Mass Transfer-Reaction Modeling of CO Capture Mediated by Immobilized Carbonic Anhydrase Enzyme on Multiscale Supporting Structures.

Environ Sci Technol

January 2025

Zhejiang Key Laboratory of Clean Energy Conversion and Utilization, Science and Education Integration College of Energy and Carbon Neutralization, Zhejiang University of Technology, Hangzhou 310014, China.

Article Synopsis
  • Immobilized carbonic anhydrase (CA) enhances CO absorption in potassium carbonate (PC) solutions, presenting a viable alternative to traditional amine-based carbon capture methods.
  • The study developed cross-scale models to assess how different enzyme immobilization materials—ranging from nanoparticle to macro-scale carriers—affect CO absorption rates, finding that nanoscale carriers are most effective.
  • While increasing enzyme activity can boost absorption rates, diffusion limits, particularly in the liquid phase, impose an upper limit to this enhancement, and smaller particle sizes below 0.35 μm significantly improve performance over benchmark solutions.
View Article and Find Full Text PDF

Metal batteries have captured significant attention for high-energy applications, owing to their superior theoretical energy densities. However, their practical viability is impeded by severe dendrite formation and poor cycling stability. To alleviate these issues, a 3D-structured bimetallic-MoTiCT based fiber electrode was fabricated in this study and analyzed experimentally and computationally.

View Article and Find Full Text PDF

Oxidative modifications can disrupt protein folds and functions, and are strongly associated with human aging and diseases. Conventional oxidation pathways typically involve the free diffusion of reactive oxygen species (ROS), which primarily attack the protein surface. Yet, it remains unclear whether and how internal protein folds capable of trapping oxygen (O) contribute to oxidative damage.

View Article and Find Full Text PDF

Real-Time Tractography-Assisted Neuronavigation for Transcranial Magnetic Stimulation.

Hum Brain Mapp

January 2025

Department of Neuroscience and Biomedical Engineering, School of Science, Aalto University, Espoo, Finland.

State-of-the-art navigated transcranial magnetic stimulation (nTMS) systems can display the TMS coil position relative to the structural magnetic resonance image (MRI) of the subject's brain and calculate the induced electric field. However, the local effect of TMS propagates via the white-matter network to different areas of the brain, and currently there is no commercial or research neuronavigation system that can highlight in real time the brain's structural connections during TMS. This lack of real-time visualization may overlook critical inter-individual differences in brain connectivity and does not provide the opportunity to target brain networks.

View Article and Find Full Text PDF

The diffusion generative model has achieved remarkable performance across various research fields. In this study, we propose a transferable graph attention diffusion model, GADIFF, for a molecular conformation generation task. With adopting multiple equivariant networks in the Markov chain, GADIFF adds GIN (Graph Isomorphism Network) to acquire local information of subgraphs with different edge types (atomic bonds, bond angle interactions, torsion angle interactions, long-range interactions) and applies MSA (Multi-head Self-attention) as noise attention mechanism to capture global molecular information, which improves the representative of features.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!