Binding of monovalent cations of increasing ionic radius to ferric cytochrome P-450cam was measured. Potassium has the highest affinity for the cation binding site observed in the X-ray crystallographic structure with Kdcat = 12 mM, compared with the smaller cation lithium, (Kdcat = 37 mM) and the larger cation cesium (Kd cat = 20 mM). Coupling between cation binding and camphor binding is established by the observation of a linear relationship between the corresponding binding free energies. Potassium binding favours a conformational change of tyrosine 96 which increases the affinity of the protein for camphor and fully dehydrates the active site.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0014-5793(94)00545-1 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Ion permeability profiles of renal paracellular channel-forming claudins.
Acta Physiol (Oxf)
February 2025
Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology, Rheumatology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Aim: Members of the claudin protein family are the major constituents of tight junction strands and determine the permeability properties of the paracellular pathway. In the kidney, each nephron segment expresses a distinct subset of claudins that form either barriers against paracellular solute transport or charge- and size-selective paracellular channels. It was the aim of the present study to determine and compare the permeation properties of these renal paracellular ion channel-forming claudins.
View Article and Find Full Text PDFImpact of ions, pH and the nature of substrate on the structure and activity of a robust single-stranded DNA binding (SSB)-like protein from Phi11.
Arch Microbiol
January 2025
Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, K K Birla Goa Campus, NH17B, Zuarinagar, Goa, 403726, India.
The gene gp13 in bacteriophage Phi11 has been annotated as a Single-Stranded DNA binding protein (SSB protein, GenBank accession no. NC_004615.1).
View Article and Find Full Text PDFEnhanced Prediction of CO-Brine Interfacial Tension at Varying Temperature Using a Multibranch-Structure-Based Neural Network Approach.
Langmuir
January 2025
Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education, School of Energy and Power Engineering, Dalian University of Technology, Dalian 116023, P. R. China.
Interfacial tension () between CO and brine depends on chemical components in multiphase systems, intricately evolving with a change in temperature. In this study, we developed a convolutional neural network with a multibranch structure (MBCNN), which, in combination with a compiled data set containing measurement data of 1716 samples from 13 available literature sources at wide temperature and pressure ranges (273.15-473.
View Article and Find Full Text PDFUltramicroporous Tröger's Base Framework Membranes With Ionized Sub-nanochannels for Efficient Acid/Alkali Recovery.
Adv Sci (Weinh)
January 2025
Research Center for Membrane and Film Technology, Department of Chemical Science and Engineering, Kobe University, Kobe, 6500034, Japan.
Membrane technology holds significant potential for the recovery of acids and alkalis from industrial wastewater systems, with ion exchange membranes (IEMs) playing a crucial role in these applications. However, conventional IEMs are limited to separating only monovalent cations or anions, presenting a significant challenge in achieving concomitant H⁺/OH⁻ permselectivity for simultaneous acid and alkali recovery. To address this issue, the charged microporous polymer framework membranes are developed, featuring rigid Tröger's Base network chains constructed through a facile sol-gel process.
View Article and Find Full Text PDFHydrated cable bacteria exhibit protonic conductivity over long distances.
Proc Natl Acad Sci U S A
January 2025
Electronics Sciences and Technology Division, United States Naval Research Laboratory, Washington, DC 20375.
This study presents the direct measurement of proton transport along filamentous , or cable bacteria. Cable bacteria are filamentous multicellular microorganisms that have garnered much interest due to their ability to serve as electrical conduits, transferring electrons over several millimeters. Our results indicate that cable bacteria can also function as protonic conduits because they contain proton wires that transport protons at distances >100 µm.
View Article and Find Full Text PDFWant 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!