A5007090899- Hemoglobin structure and function
- Heme Oxygenase-1 and Carbon Monoxide
- Nitric Oxide and Endothelin Effects
- Electron Spin Resonance Studies
- Neonatal Health and Biochemistry
- Sulfur Compounds in Biology
- Porphyrin and Phthalocyanine Chemistry
- Porphyrin Metabolism and Disorders
- Electrochemical sensors and biosensors
- Protein Interaction Studies and Fluorescence Analysis
- Photosynthetic Processes and Mechanisms
- Metal-Catalyzed Oxygenation Mechanisms
- Monoclonal and Polyclonal Antibodies Research
- Vanadium and Halogenation Chemistry
- Analytical Chemistry and Sensors
- Magnetism in coordination complexes
- Redox biology and oxidative stress
- Photodynamic Therapy Research Studies
- Light effects on plants
- Renin-Angiotensin System Studies
- Receptor Mechanisms and Signaling
- Spectroscopy and Quantum Chemical Studies
- Molecular Sensors and Ion Detection
- SARS-CoV-2 and COVID-19 Research
- Physiological and biochemical adaptations
University of Buenos Aires
2016-2025
Consejo Nacional de Investigaciones Científicas y Técnicas
2016-2025
Instituto de Química y Fisicoquímica Biológicas
1997-2025
Fundación Ciencias Exactas y Naturales
2005-2020
Institute of Astronomy and Space Physics
2018
National University of Mar del Plata
2003-2009
Bar-Ilan University
1982
Fluorescence, the absorption of short-wavelength electromagnetic radiation reemitted at longer wavelengths, has been suggested to play several biological roles in metazoans. This phenomenon is uncommon tetrapods, being restricted mostly parrots and marine turtles. We report fluorescence amphibians, tree frog Hypsiboas punctatus, showing that living frogs produced by a combination lymph glandular emission, with pigmentary cell filtering skin. The chemical origin was traced class fluorescent...
The water-soluble manganese(III) meso-tetrakis (N-ethylpyridinium-2-yl) porphyrin (MnIIITEPyP) and meso-(tetrakis(4-sulfonato-phenyl)) porphyrinate (MnIIITPPS) are able to chemically distinguish between HNO NO donors, reacting with the former in a fast, efficient, selective manner concomitant formation of {MnNO}7 complex (kon(HNO) ≈ 105 M-1 s-1), while they inert or react very slowly donors. DFT calculations kinetic data suggest that trapping is operative at least case MnIIITPPS, catalytic...
Nitroxyl (HNO/NO−) heme-adducts have been postulated as intermediates in a variety of catalytic processes carried out by different metalloenzymes. Hence, there is growing interest obtaining and characterizing heme model nitroxyl complexes. The one-electron chemical reduction the {FeNO}7 nitrosyl derivative FeIII(TFPPBr8)Cl, FeII(TFPPBr8)NO (1) (TFPPBr8 = 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-[Tetrakis-(pentafluorophenyl)]porphyrin) with cobaltocene yields significantly stable {FeNO}8...
Abstract Not so elusive : [Fe II (CN) 5 (HNO)] 3− has been characterized spectroscopically after the two‐electron reduction of nitroprusside (see scheme). The complex is stable at pH 6, slowly decomposing to [Fe(CN) 6 ] 4− and N 2 O. It deprotonated increasing value with oxidation bound NO − (NO)] . first non‐heme iron–nitroxyl prepared in aqueous solution that reversibly redox‐active under biologically relevant conditions. magnified image
Since the beginning of COVID-19 pandemic, there has been a significant need to develop antivirals and vaccines combat disease. In this work, we developed llama-derived nanobodies (Nbs) directed against receptor binding domain (RBD) other domains Spike (S) protein SARS-CoV-2. Most Nbs with neutralizing properties were RBD able block S-2P/ACE2 interaction. Three recognized N-terminal (NTD) S-2P protein. Intranasal administration induced protection ranging from 40% 80% after challenge WA1/2020...
Iron(II) porphyrin nitrosyl complexes are obtained in high yields from the reaction of iron(III) porphyrins with nitroxyl donors sodium trioxodinitrate and toluensulfohydroxamic acid. The was found to proceed both organic solvents aqueous media (meso-tetraphenyl) porphyrinate ([FeIII(TPP)]+) meso-tetrakis (4-sulfonatophenyl) ([FeIII(TPPS)]3-) or protoporphyrin IX, respectively. kinetic rate constant for (kon) estimated be 1.00 ± 0.04 × 107 M-1 s-1. As well as resulting a versatile method...
The reactivity of inorganic sulfide species toward heme peptides was explored under biorelevant conditions in order to unravel the molecular details endogenous hydrogen proteins. Unlike ferric porphyrinates, which are reduced by sulfide, some proteins can form stable Fe(III)-sulfide adducts. To isolate protein factors ruling redox chemistry, we used as a system model, undecapeptide microperoxidase (MP11), peptide derived from cytochrome c proteolysis that retains proximal histidine bound...
Significance Green coloration of vertebrates is normally attributed to pigments and structural components inside skin chromatophores cells. However, these do not account for the vivid blue-green colors hundreds species frogs with sparse chromatophores. Our study shows that green originates in proteins serpin superfamily bind pigment biliverdin, modulating its absorbance properties. Using a South American treefrog, we demonstrated serpins have clear ecological role reflectance properties...
Hydrogen sulfide (H2S) was recently discovered as a gasotransmitter, capable of coordinating to the heme iron hemeproteins. H2S is unique for its ability render varying concentrations nucleophilic conjugate bases (HS(-) or S(2-)), either free bound species with expected outcomes on further reactivity. There no direct evidence about which (H2S, HS(-), S(2-)) coordinates iron. We performed computer simulations address migration and binding processes hemoglobin I Lucina pectinata, exhibits...
Summary There is a growing body of evidence on the role nitric oxide (NO) in human platelet physiology regulation. Recently, interest has developed functional an alternative redox form NO, namely nitroxyl (HNO/NO-), because it formed by number diverse biochemical reactions. The aim present study was to comparatively analyze effect HNO and NO several parameters platelets. For this purpose, sodium trioxodinitrate (Angeli’s salt, AS) nitroprusside (SNP) were used as releasers, respectively....
The reaction of hydrogen sulfide (H2S) with hemeproteins is a key physiological reaction; still, its mechanism and implications are not completely understood. In this work, we propose combination experimental theoretical tools to shed light on the in model system microperoxidase 11 (MP11-FeIII) myoglobin (Mb-FeIII), from estimation intrinsic binding constants species H2S hydrosulfide (HS-), computational description overall process. Our results show that HS- main reactive Mb-FeIII...
The one electron reduction of nitrite to NO, catalyzed in vivo by a group enzymes called reductases (NIRs), has been extensively investigated due its relevance the processes denitrification. heme containing NIRs are soluble noncovalent homodimers with two groups each subunit: d1 heme, site reduction, and type c responsible for internal transfer. High resolution X-ray structures show that all have distal histidines active as common feature. We analyzed reaction mechanism Pseudomonas...
Class B G protein-coupled receptors (GPCRs) are involved in a variety of human pathophysiological states. These groups membrane less studied than class A GPCRs due to the lack structural information, delayed small molecule drug discovery, and scarce fluorescence detection tools available. The corticotropin-releasing hormone type 1 receptor (CRHR1) is key player stress response whose dysregulation critically stress-related disorders: psychiatric conditions (i.e. depression, anxiety,...