Isothermal titration calorimetry (ITC) was used to quantify the thermodynamics of Pb(2+) and Zn(2+) binding metallothionein-3 (MT-3). binds zinc-replete Zn7MT-3 displacing each zinc ion with a similar change in free energy (ΔG) enthalpy (ΔH). EDTA chelation measurements Pb7MT-3 reveal that both metal ions are extracted tri-phasic process, indicating they bind protein three populations different thermodynamics. Metal is entropically favoured, an enthalpic penalty reflects cost cysteine...

A robust method for the preparation, stabilization and delivery of Cu⁺ aqueous titrations, in particular ITC measurements, is described.

An artificial metalloenzyme reduces CO₂ to CO using light, suggesting intramolecular electron transfer and secondary sphere effects modulate catalytic selectivity.

In bacterial resistance to mercury, the organomercurial lyase (MerB) plays a key role in detoxification pathway through its ability cleave Hg-carbon bonds. Two cysteines (C96 and C159; Escherichia coli MerB numbering) an aspartic acid (D99) have been identified as catalytic residues, these three residues are conserved all but four known variants, where is replaced with serine. To understand of active site serine, we characterized structure metal binding properties E. mutant serine...

Abstract An enzymatic system for light‐driven hydrogen generation has been developed through covalent attachment of a ruthenium chromophore to nickel‐substituted rubredoxin (NiRd). The photoinduced activity the hybrid enzyme is significantly greater than that two‐component and strongly dependent on position phototrigger relative active site, indicating role intramolecular electron transfer in catalysis. Steady‐state time‐resolved emission spectra reveal pathway rapid, direct quenching...

The organomercurial lyase MerB has the unique ability to cleave carbon-Hg bonds, and structural studies indicate that three residues in active site (C96, D99, C159 E. coli MerB) play important roles bond cleavage. However, role of each residue carbon-metal cleavage not been well-defined. To do so, we have structurally biophysically characterized interaction with a series organotin organolead compounds. Studies two known inhibitors MerB, dimethyltin (DMT) triethyltin (TET), reveal they...

The field of solar fuels is a rapidly growing area research, though low overall efficiencies continue to preclude large-scale implementation. To resolve the elementary processes involved in light-driven energy storage and identify key factors contributing efficiency losses, systematic investigation optimization are necessary. In this work, ruthenium chromophore directly attached model hydrogenase enzyme, nickel-substituted rubredoxin, construct molecular system capable photoinduced hydrogen...

The mitochondrial calcium uniporter (MCU) inhibitors Ru265 and Os245 were functionalized with adamantane to make them amenable for encapsulation in cucurbituril. resulting host–guest complexes investigated their biological properties.

The connecting peptide (C-peptide) is a hormone with promising health benefits in ameliorating diabetes-related complications, yet mechanisms remain elusive. Emerging studies point to possible dependence of activity on bioavailable metals, particularly Cu(II) and Zn(II). However, little known about the chemical nature interactions, hindering advances its therapeutic applications. This work uncovers Cu(II)-binding site C-peptide that may be key understanding metal-dependent function. A...

Oxytocin is a 9-amino acid peptide hormone. Since its discovery in 1954, it has most commonly been studied relation to role stimulating parturition and lactation. However, now known that oxytocin widely diverse set of functions throughout the body including neuromodulation, bone growth, inflammation. Previous research suggested divalent metal ions may be required for activity, but exact species specific pathways have yet fully elucidated. In this work, we focus on characterizing copper zinc...

The connecting peptide (C-peptide) has received increased attention for its potential therapeutic effects in ameliorating illnesses such as kidney disease and diabetes. Although the mechanism of C-peptide signaling remains elusive, evidence supports internalization intracellular function. Emerging research is uncovering diverse biological roles metals play controlling affecting function bioactive peptides. work presented herein investigates interactions between first-row d-block transition...

ADVERTISEMENT RETURN TO ISSUEPREVViewpointNEXTSounding Out Dysfunctional Oxygen Metabolism: A Small-Molecule Probe for Photoacoustic Imaging of HypoxiaMichael J. Stevenson and Marie C. Heffern*View Author Information Department Chemistry, University California, Davis, One Shields Avenue, California 95616, United States*E-mail: [email protected]Cite this: Biochemistry 2018, 57, 6, 893–894Publication Date (Web):January 24, 2018Publication History Received3 January 2018Published online24...

Peptide hormones are essential signaling molecules with therapeutic importance. Identifying regulatory factors that drive their activity gives important insight into mode of action and clinical development. In this work, we demonstrate the combined impact Cu(II) serum protein albumin on C-peptide, a 31-mer peptide derived from same prohormone as insulin. C-peptide exhibits beneficial effects, particularly in diabetic patients, but its use has been hampered by lack mechanistic understanding....

Copper(II) is an essential metal in biological systems, conferring unique chemical properties to the biomolecules with which it interacts. It has been reported directly bind a variety of peptides and play both necessary pathological roles ranging from mediating structure electron transfer imparting catalytic function. Quantifying binding affinity thermodynamics these Cu(II)-peptide complexes vitro provides insight into thermodynamic driving force binding, potential competitions between...

Nickel‐substituted rubredoxin (NiRd) has been shown to serve as a functional mimic of nickel‐containing hydrogenases, able produce hydrogen gas with high catalytic rates. In the native enzyme, nickel center is coordinated by four cysteine thiolates. A similar environment seen in NiRd, which represents first model reproduce this coordination motif. This 52‐residue protein stable under wide range conditions, making it well‐suited for production or future fuel cells. Although much known about...

The proinsulin connecting peptide, C-peptide, is released in equimolar amounts and might be an active hormone. exact function of C-peptide remains unclear, but its activity depend on metal ions. As depicted this cover art, bioavailable metals could the missing piece to elucidate C-peptide′s activity. More information can found communication by M. C. Heffern et al. page 2447 Issue 19, 2019 (DOI: 10.1002/cbic.201900172).

Copper(II) is an essential metal in biological systems, conferring unique chemical properties to the biomolecules with which it interacts. It has been reported directly bind a variety of peptides and play both necessary pathological roles ranging from mediating structure electron transfer imparting catalytic function. Quantifying binding affinity thermodynamics these Cu(II)-peptide complexes vitro provides insight into thermodynamic driving force binding, potential competitions between...