The metal ions in insulin hexamer play a crucial role in the T to R conformational transitions. We have determined the crystal structures of 2Mn2+, 1Rb1+ and 4Ni2+ human arg-insulin and compared them with the 2Zn2+ structure. The first two structures exist in the T3R3f state like the native 2Zn2+ arg-insulin, while the 4Ni2+ adopts a T6 conformation. The metal coordination is found to be tetrahedral in all the structures except that of nickel where a dual octahedral and tetrahedral coordination is found at one site. Rubidium occupies only one of the high affinity metal binding sites. The metal induced structural changes observed, have been explained.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.ijbiomac.2008.09.019 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Secondary Coordination Effects of Adjacent Metal Center in Metal-Nitrogen-Carbon Improve Scaling Relation of Oxygen Electrocatalysis.
J Phys Chem Lett
January 2025
Hefei National Research Center for Physical Sciences at the Microscale, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026, China.
Heterogenous single-atom catalysts (SACs) are reminiscent of homogeneous catalysts because of the similarity of structural motif of active sites, showing the potential of using the advantage of homogeneous catalysts to tackle challenges in hetereogenous catalysis. In heterogeneous oxygen electrocatalysis, the homogeneity of adsorption patterns of reaction intermediates leads to scaling relationships that limit their activities. In contrast, homogeneous catalysts can circumvent such limits by selectively altering the adsorption of intermediates through secondary coordination effects (SCEs).
View Article and Find Full Text PDFThe Impact of Electrophysiological Diversity on Pattern Completion in Lithium Nonresponsive Bipolar Disorder: A Computational Modeling Approach.
Brain Behav
January 2025
Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada.
Introduction: Patients with bipolar disorder (BD) demonstrate episodic memory deficits, which may be hippocampal-dependent and may be attenuated in lithium responders. Induced pluripotent stem cell-derived CA3 pyramidal cell-like neurons show significant hyperexcitability in lithium-responsive BD patients, while lithium nonresponders show marked variance in hyperexcitability. We hypothesize that this variable excitability will impair episodic memory recall, as assessed by cued retrieval (pattern completion) within a computational model of the hippocampal CA3.
View Article and Find Full Text PDFRevisiting Dipole-Induced Fluorinated-Anion Decomposition Reaction for Promoting a LiF-Rich Interphase in Lithium-Metal Batteries.
Nanomicro Lett
January 2025
Henan Institutes of Advanced Technology, Zhengzhou University, Zhengzhou, 450003, People's Republic of China.
Building anion-derived solid electrolyte interphase (SEI) with enriched LiF is considered the most promising strategy to address inferior safety features and poor cyclability of lithium-metal batteries (LMBs). Herein, we discover that, instead of direct electron transfer from surface polar groups to bis(trifluoromethanesulfonyl)imide (TFSI) for inducing a LiF-rich SEI, the dipole-induced fluorinated-anion decomposition reaction begins with the adsorption of Li ions and is highly dependent on their mobility on the polar surface. To demonstrate this, a single-layer graphdiyne on MXene (sGDY@MXene) heterostructure has been successfully fabricated and integrated into polypropylene separators.
View Article and Find Full Text PDFMetal-organic frameworks encapsulating gold nanoclusters and carbon dots for ratiometric fluorescent detection of formaldehyde in real food samples, construction materials and indoor environments.
Mikrochim Acta
January 2025
Hebei Lansheng Bio-Tech Co, Ltd, Shijiazhuang, 052263, P. R. China.
A novel fluorescence sensing nanoplatform (CDs/AuNCs@ZIF-8) encapsulating carbon dots (CDs) and gold nanoclusters (AuNCs) within a zeolitic imidazolate framework-8 (ZIF-8) was developed for ratiometric detection of formaldehyde (FA) in the medium of hydroxylamine hydrochloride (NHOH·HCl). The nanoplatform exhibited pink fluorescence due to the aggregation-induced emission (AIE) effect of AuNCs and the internal filtration effect (IFE) between AuNCs and CDs. Upon reaction between NHOH·HCl and FA, a Schiff base formed via aldehyde-diamine condensation, releasing hydrochloric acid.
View Article and Find Full Text PDFVisible-Light-Induced Insertion of Siloxycarbene into Amide N-H Bonds: Synthesis of Carbinolamides from Acylsilanes and Amides.
J Org Chem
January 2025
Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India.
The insertion of carbene into secondary amide N-H bonds remains underexplored in organic synthesis. In this work, we discovered the visible-light-induced insertion of siloxycarbene into amide N-H bonds. This metal-free, facile reaction proceeds with atom economy under mild conditions with a broad range of secondary N-H amides, including benzanilide, acetanilide, oxindole, isatin, quinolinone, and maleimide, affording stable - and -acetals in excellent isolated yields.
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!