Mucus in the colon is crucial for intestinal homeostasis by forming a barrier that separates microbes from the epithelium. This is achieved by the structural arrangement of the major mucus proteins, such as MUC2 and FCGBP, both of which are comprised of several von Willebrand D domains (vWD) and assemblies. Numerous disulfide bonds stabilise these domains, and intermolecular bonds generate multimers of MUC2.
View Article and Find Full Text PDFBackground: Bivalent regions of chromatin (BvCR) are characterized by trimethylated lysine 4 (H3K4me3) and lysine 27 on histone H3 (H3K27me3) deposition which aid gene expression control during cell differentiation. The role of BvCR in post-transcriptional DNA damage response remains unidentified. Oncoprotein survivin binds chromatin and mediates IFNγ effects in CD4 cells.
View Article and Find Full Text PDFThe MUC2 mucin protects the colonic epithelium by a two-layered mucus with an inner attached bacteria-free layer and an outer layer harboring commensal bacteria. CysD domains are 100 amino-acid-long sequences containing 10 cysteines that separate highly O-glycosylated proline, threonine, serine (PTS) regions in mucins. The structure of the second CysD, CysD2, of MUC2 is now solved by nuclear magnetic resonance.
View Article and Find Full Text PDFHaloferax mediterranei, an extreme halophilic archaeon thriving in hypersaline environments, has acquired significant attention in biotechnological and biochemical research due to its remarkable ability to flourish in extreme salinity conditions. Transcription factors, essential in regulating diverse cellular processes, have become focal points in understanding its adaptability. This study delves into the role of the Lrp transcription factor, exploring its modulation of glnA, nasABC, and lrp gene promoters in vivo through β-galactosidase assays.
View Article and Find Full Text PDFThe microbiota inhabits the gastrointestinal tract, providing essential capacities to the host. The microbiota is a crucial factor in intestinal health and regulates intestinal physiology. However, microbiota disturbances, named dysbiosis, can disrupt intestinal homeostasis, leading to the development of diseases.
View Article and Find Full Text PDFThe MUC2 mucin polymer is the main building unit of the intestinal mucus layers separating intestinal microbiota from the host epithelium. The MUC2 mucin is a large glycoprotein with a C-terminal domain similar to the MUC5AC and MUC5B mucins and the von Willebrand factor (VWF). A structural model of the C-terminal part of MUC2, MUC2-C, was generated by combining Cryo-electron microscopy, AlphaFold prediction, information of its glycosylation, and small angle X-ray scattering information.
View Article and Find Full Text PDFIn this study, we explore the role of nuclear survivin in maintaining the effector phenotype of IFNγ-producing T cells acting through the transcriptional control of glucose utilization. High expression of survivin in CD4T cells was associated with IFNγ-dependent phenotype and anaerobic glycolysis. Transcriptome of CD4 cells and sequencing of survivin-bound chromatin showed that nuclear survivin had a genome-wide and motif-specific binding to regulatory regions of the genes controlling cell metabolism.
View Article and Find Full Text PDFActa Crystallogr D Struct Biol
June 2022
Serial crystallography is a rapidly growing method that can yield structural insights from microcrystals that were previously considered to be too small to be useful in conventional X-ray crystallography. Here, conditions for growing microcrystals of the photosynthetic reaction centre of Blastochloris viridis within a lipidic cubic phase (LCP) crystallization matrix that employ a seeding protocol utilizing detergent-grown crystals with a different crystal packing are described. LCP microcrystals diffracted to 2.
View Article and Find Full Text PDFProper physiological functioning of any cell type requires ordered chromatin organization. In this context, cohesin complex performs important functions preventing premature separation of sister chromatids after DNA replication. In partnership with CCCTC-binding factor, it ensures insulator activity to organize enhancers and promoters within regulatory chromatin.
View Article and Find Full Text PDFMucus forms an important protective barrier that minimizes bacterial contact with the colonic epithelium. Intestinal mucus is organized in a complex network with several specific proteins, including the mucin-2 (MUC2) and the abundant IgGFc-binding protein, FCGBP. FCGBP is expressed in all intestinal goblet cells and is secreted into the mucus.
View Article and Find Full Text PDFis an extremely halophilic archaeon, able to live in hypersaline environments with versatile nutritional requirements, whose study represents an excellent basis in the field of biotechnology. The transcriptional machinery in combines the eukaryotic basal apparatus and the bacterial regulation mechanisms. However, little is known about molecular mechanisms of gene expression regulation compared with , particularly in Haloarchaea.
View Article and Find Full Text PDFProtein dynamics contribute to protein function on different time scales. Ultrafast X-ray diffraction snapshots can visualize the location and amplitude of atom displacements after perturbation. Since amplitudes of ultrafast motions are small, high-quality X-ray diffraction data is necessary for detection.
View Article and Find Full Text PDFLow-frequency vibrations are crucial for protein structure and function, but only a few experimental techniques can shine light on them. The main challenge when addressing protein dynamics in the terahertz domain is the ubiquitous water that exhibit strong absorption. In this paper, we observe the protein atoms directly using X-ray crystallography in bovine trypsin at 100 K while irradiating the crystals with 0.
View Article and Find Full Text PDFActa Crystallogr A Found Adv
November 2019
Single-wavelength X-ray anomalous diffraction (SAD) is a frequently employed technique to solve the phase problem in X-ray crystallography. The precision and accuracy of recovered anomalous differences are crucial for determining the correct phases. Continuous rotation (CR) and inverse-beam geometry (IBG) anomalous data collection methods have been performed on tetragonal lysozyme and monoclinic survivin crystals and analysis carried out of how correlated the pairs of Friedel's reflections are after scaling.
View Article and Find Full Text PDFAlthough virtual and augmented reality (VR and AR) techniques have been used extensively in specialized laboratories, only recently did they become affordable, reaching wider consumer markets. With increased availability, it is timely to examine the roles that VR and AR may play in teaching structural biology and in experiencing complex data sets such as macromolecular structures. This guide is suitable for those teachers of structural biology who do not have a deep knowledge of information technologies.
View Article and Find Full Text PDFA biomolecular ensemble exhibits different responses to a temperature gradient depending on its diffusion properties. MicroScale Thermophoresis technique exploits this effect and is becoming a popular technique for analyzing interactions of biomolecules in solution. When comparing affinities of related compounds, the reliability of the determined thermodynamic parameters often comes into question.
View Article and Find Full Text PDFActa Crystallogr A Found Adv
May 2016
In experimental research referencing two or more measurements to one another is a powerful tool to reduce the effect of systematic errors between different sets of measurements. The interesting quantity is usually derived from two measurements on the same sample under different conditions. While an elaborate experimental design is essential for improving the estimate, the data analysis should also maximally exploit the covariance between the measurements.
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