Insight into the Gas-Phase Structure of a Copper(II) l-Histidine Complex, the Agent Used To Treat Menkes Disease

Abstract

Copper(II) L-histidine is used in the treatment of a rare neurological disease called Menkes disease. An infrared multiple photon dissociation (IRMPD) vibrational spectrum of the gas-phase copper(II) L-histidine complex has been obtained. This spectrum was compared to lowest-energy computational spectra obtained at the B3LYP/6-311+G** level of theory. Two species, CuHis1 and CuHis2, are very close in Gibbs free energy, and both have computed vibrational spectra in good agreement with the experimentally observed IRMPD spectrum. The first structure exhibits four histidine-copper interactions in the same plane and a fifth out-of-plane interaction. The second structure exhibits four histidine-copper interactions in the same plane. The fact that the experimental and computational spectra are found to be in good agreement adds considerable insight into the gas-phase structure of the copper(II) L-histidine complex.

Cisplatin Primary Complex with l‐Histidine Target Revealed by IR Multiple Photon Dissociation (IRMPD) Spectroscopy

“…A glycine‐linked cisplatin complex, [(Gly‐H)PtCl 2 ] − , has also provided a case study for IRMPD experiments that was interpreted based on a survey of hybrid theoretical approaches . Metal ion (alkali metals, Cu II , Zn II , Cd II ) complexes with His ligand(s) have also been successfully assayed …”

“…[18] Metal ion (alkali metals,C u II ,Z n II ,C d II ) complexes with His ligand(s) have also been successfully assayed. [19][20][21][22] 2. Results and Discussion cis-[PtCl(NH 3 ) 2 (His)] + complexes are directly revealed by ESI-MS as distincti onic products from the reaction of cisplatin and His (mass spectrum shown in Figure S1 in the Supporting Information).…”

Amino Acid Oxidation: A Combined Study of Cysteine Oxo Forms by IRMPD Spectroscopy and Simulations

“…The inherent bonding and conformational features of cysteine in its (de)protonated, nitrosated, and metal‐tagged forms have been previously interrogated both in the free amino acid and in the residue embodied in the glutathione peptide by a joint computational and experimental infrared multiple photon dissociation (IRMPD) assay. IRMPD spectroscopy, coupled with ESI tandem mass spectrometry (MS/MS), is a pivotal tool to provide direct structural clues about gaseous (bio)molecular ions, including (de)protonation site, metal‐binding patterns, and local intramolecular interactions in both native and modified amino acids and peptides, DNA/RNA bases and nucleotides, cluster ions, and fragmentation products …”

“…[18] Recently,avariety of mass spectrometric studies have been able to identify the reactive intermediates formed by (interfacial) ozonolysis of deprotonated cysteineatthe air-liquid interface, [5,19] to probe the stability and fragmentation behavior of intact and modified sulfinyl radical ions, [20,21] and elucidate the intrinsic mechanism involved in the formationo fc ysteine oxo forms [cysSO x ] À (x = 1, 2, 3) and sulfenate radicala nions in the gas phase. [22] The unambiguous and detailed characterization of the structurala nd dynamic behavior of theset ransient intermediates in isolated environments, in which external interferences are absent,w ill help to reveali ntrinsic properties rele-vant to their biological activity.T he inherentb onding and conformationalf eatureso fc ysteine in its (de)protonated, [23,24] nitrosated, [25] and metal-tagged [26] forms have been previously interrogated both in the free amino acid and in the residue embodied in the glutathione peptide [27] by aj oint computational and experimental infrared multiple photon dissociation (IRMPD) assay.I RMPD spectroscopy,c oupled with ESI tandem mass spectrometry (MS/MS), is ap ivotalt ool to provide direct structural clues about gaseous (bio)molecular ions, [28][29][30][31][32][33] including (de)protonations ite, metal-binding patterns,a nd local intramolecular interactions in both native and modified amino acids and peptides, [34][35][36][37][38][39][40][41][42] DNA/RNA bases and nucleotides, [43][44][45] cluster ions, [46] and fragmentation products. [47] We now examine the intrinsic chemical properties and geometric features of the conjugate bases of cysteine sulfenic, sulfinic, and sulfonica cids, [cysSO x ] À (x = 1, 2, 3), by meanso fE SI/ MS-IRMPD spectroscopy in the highly informativem id-IR spectral range (750-1900 cm À1 )i nc ombination with ab initio...…”

Binding motifs of cisplatin interaction with simple biomolecules and aminoacid targets probed by IR ion spectroscopy

“…Indeed, detailed structural information about gaseous charged species is currently available using this "action" IR spectroscopy, based on the photofragmentation process induced by the non-coherent absorption of IR photons in resonance with active vibrational modes [21][22][23][24][25][26][27]. A wide variety of transition metal complexes have already been characterized by IRMPD spectroscopy, such as, for example, metastable reduced zinc complexes [28], copper resveratrol complexes [29], Zn-salophen complexes with chemosensing properties [30], besides various complexes presenting amino acids and peptides bound to transition metals [31][32][33][34][35].…”