The Effect of the Protein Synthesis Entropy Reduction on the Cell Size Regulation and Division Size of Unicellular Organisms

2 days 14 hours ago
The underlying mechanism determining the size of a particular cell is one of the fundamental unknowns in cell biology. Here, using a new approach that could be used for most of unicellular species, we show that the protein synthesis and cell size are interconnected biophysically and that protein synthesis may be the chief mechanism in establishing size limitations of unicellular organisms. This result is obtained based on the free energy balance equation of protein synthesis and the second law...
Mohammad Razavi

Thermal hysteresis in microtubule assembly/disassembly dynamics: The aging-induced degradation of tubulin dimers

6 days 14 hours ago
The assembly/disassembly of biological macromolecules plays an important role in their biological functionalities. Although the dynamics of tubulin polymers and their super-assembly into microtubule structures is critical for many cellular processes, details of their cyclical polymerization/depolymerization are not fully understood. Here, we use a specially designed light scattering technique to continuously examine the effects of temperature cycling on the process of microtubule...
R Wu

A Nanometric Probe of the Local Proton Concentration in Microtubule-Based Biophysical Systems

3 weeks 5 days ago
We show a double-functional fluorescence sensing paradigm that can retrieve nanometric pH information on biological structures. We use this method to measure the extent of protonic condensation around microtubules, which are protein polymers that play many roles crucial to cell function. While microtubules are believed to have a profound impact on the local cytoplasmic pH, this has been hard to show experimentally due to the limitations of conventional sensing techniques. We show that subtle...
Aarat P Kalra

Novel colchicine derivative CR42-24 demonstrates potent anti-tumor activity in urothelial carcinoma

1 month 3 weeks ago
Bladder cancers, and specifically urothelial carcinoma, have few effective treatment options, and tumors typically develop resistance against standard of care chemotherapies leading to significant mortality. The development of alternative therapies with increased selectivity and improved tolerability would significantly impact this patient population. Here, we investigate a novel colchicine derivative, CR42-24, with increased selectivity for the βIII tubulin subtype as a treatment for urothelial...
Clayton J Bell

Disassembly of microtubules by intense terahertz pulses

2 months 4 weeks ago
The biological effects of terahertz (THz) radiation have been observed across multiple levels of biological organization, however the sub-cellular mechanisms underlying the phenotypic changes remain to be elucidated. Filamentous protein complexes such as microtubules are essential cytoskeletal structures that regulate diverse biological functions, and these may be an important target for THz interactions underlying THz-induced effects observed at the cellular or tissue level. Here, we show...
Cameron M Hough

Computational determination of toxicity risks associated with a selection of approved drugs having demonstrated activity against COVID-19

3 months ago
CONCLUSION: In summary, this manuscript aims to provide a potentially useful source of essential knowledge on toxicity assessment of 90 compounds for healthcare practitioners and researchers to find off-label alternatives for the treatment for COVID-19. The majority of the molecules discussed in this manuscript have already moved into clinical trials and thus their known pharmacological and human safety profiles are expected to facilitate a fast track preclinical and clinical assessment for...
Maral Aminpour

Computational Study of Potential Galectin-3 Inhibitors in the Treatment of COVID-19

3 months 3 weeks ago
Galectin-3 is a carbohydrate-binding protein and the most studied member of the galectin family. It regulates several functions throughout the body, among which are inflammation and post-injury remodelling. Recent studies have highlighted the similarity between Galectin-3's carbohydrate recognition domain and the so-called "galectin fold" present on the N-terminal domain of the S1 sub-unit of the SARS-CoV-2 spike protein. Sialic acids binding to the N-terminal domain of the Spike protein are...
Maral Aminpour

<em>In silico</em> identification of RBD subdomain of spike protein from Pro<sup>322</sup>-Thr<sup>581</sup> for applications in vaccine development against SARS-CoV2

8 months 1 week ago
The three-dimensional hybrid structures of coronavirus spike proteins including the C-terminal sequence and receptor binding motif (RBM) was remodeled and energy minimized. Further, protein-protein docking show that Receptor Binding Domain (RBD) of SARS-CoV 2 Lys^(457)-Pro^(490) bind on the surface of ACE2 receptor near N-terminal helices to form host-pathogen attachment. In this binding interface, SARS-CoV 2 shows a tight network of hydrogen bonds than other spike proteins from BtRsRaTG13-CoV,...
Nataraj S Pagadala

Modeling Microtubule Counterion Distributions and Conductivity Using the Poisson-Boltzmann Equation

9 months 1 week ago
Microtubules are highly negatively charged proteins which have been shown to behave as bio-nanowires capable of conducting ionic currents. The electrical characteristics of microtubules are highly complicated and have been the subject of previous work; however, the impact of the ionic concentration of the buffer solution on microtubule electrical properties has often been overlooked. In this work we use the non-linear Poisson Boltzmann equation, modified to account for a variable permittivity...
Boden B Eakins

The Uniqueness of Albumin as a Carrier in Nanodrug Delivery

9 months 3 weeks ago
Albumin is an appealing carrier in nanomedicine because of its unique features. First, it is the most abundant protein in plasma, endowing high biocompatibility, biodegradability, nonimmunogenicity, and safety for its clinical application. Second, albumin chemical structure and conformation allows interaction with many different drugs, potentially protecting them from elimination and metabolism in vivo, thus improving their pharmacokinetic properties. Finally, albumin can interact with receptors...
Alessandra Spada

Insights into the interaction dynamics between volatile anesthetics and tubulin through computational molecular modelling

10 months 1 week ago
General anesthetics, able to reversibly suppress all conscious brain activity, have baffled medical science for decades, and little is known about their exact molecular mechanism of action. Given the recent scientific interest in the exploration of microtubules as putative functional targets of anesthetics, and the involvement thereof in neurodegenerative disorders, the present work focuses on the investigation of the interaction between human tubulin and four volatile anesthetics: ethylene,...
Eric A Zizzi

First Search for Dyons with the Full MoEDAL Trapping Detector in 13 TeV pp Collisions

10 months 2 weeks ago
The MoEDAL trapping detector consists of approximately 800 kg of aluminum volumes. It was exposed during run 2 of the LHC program to 6.46 fb^{-1} of 13 TeV proton-proton collisions at the LHCb interaction point. Evidence for dyons (particles with electric and magnetic charge) captured in the trapping detector was sought by passing the aluminum volumes comprising the detector through a superconducting quantum interference device (SQUID) magnetometer. The presence of a trapped dyon would be...
B Acharya

An insight into the anticancer potential of carbamates and thiocarbamates of 10-demethoxy-10-methylaminocolchicine

11 months ago
Colchicine shows very high antimitotic activity, therefore, it is used as a lead compound for generation of new anticancer agents. In the hope of developing novel, useful drugs with more favourable pharmacological profiles, a series of doubly modified colchicine derivatives has been designed, synthesized and characterized. These novel carbamate or thiocarbamate derivatives of 10-demethoxy-10-methylaminocolchicine have been tested for their antiproliferative activity against four human cancer...
Julia Krzywik

JAK inhibitors in immune-mediated rheumatic diseases: From a molecular perspective to clinical studies

1 year ago
The Janus Kinase signalling pathway is implicated in the pathogenesis of immune-related diseases. The potency of small-molecule Janus Kinase inhibitors in the treatment of inflammatory diseases demonstrates that this pathway can be successfully targeted for therapeutic purposes. The outstanding relevant questions concerning drugs' efficacy and toxicity challenge the research to enhance the selectivity of these drugs. The promising results of computational techniques, such as Molecular Dynamics...
Michela Sperti

Modeling the structure of the frameshift-stimulatory pseudoknot in SARS-CoV-2 reveals multiple possible conformers

1 year ago
The coronavirus causing the COVID-19 pandemic, SARS-CoV-2, uses -1 programmed ribosomal frameshifting (-1 PRF) to control the relative expression of viral proteins. As modulating -1 PRF can inhibit viral replication, the RNA pseudoknot stimulating -1 PRF may be a fruitful target for therapeutics treating COVID-19. We modeled the unusual 3-stem structure of the stimulatory pseudoknot of SARS-CoV-2 computationally, using multiple blind structural prediction tools followed by μs-long molecular...
Sara Ibrahim Omar

Synthesis, anticancer activity and molecular docking studies of N-deacetylthiocolchicine and 4-iodo-N-deacetylthiocolchicine derivatives

1 year ago
Colchicine is a plant alkaloid with a broad spectrum of biological and pharmacological properties. It has found application as an anti-inflammatory agent and also shows anticancer effects through its ability to destabilize microtubules by preventing tubulin dimers from polymerizing leading to mitotic death. However, adverse side effects have so far restricted its use in cancer therapy. This has led to renewed efforts to identify less toxic derivatives. In this article, we describe the synthesis...
Greta Klejborowska