Post-Translational Oxidative Modifications of Hemostasis Proteins: Structure, Function, and Regulation.

Reactive oxygen species (ROS) are constantly generated in a living organism. An imbalance between the amount of generated reactive species in the body and their destruction leads to the development of oxidative stress. Proteins are extremely vulnerable targets for ROS molecules, which can cause oxidative modifications of amino acid residues, thus altering structure and function of intra- and extracellular proteins.

Life Cycle of Functional All-Green Biocompatible Fibrous Materials Based on Biodegradable Polyhydroxybutyrate and Hemin: Synthesis, Service Life, and the End-of-Life via Biodegradation.

This article addresses the entire life cycle of the all-green fibrous materials based on poly(3-hydroxybutyrate) (PHB) containing a natural biocompatible additive Hemin (Hmi): from preparation, service life, and the end of life upon in-soil biodegradation. Fibrous PHB/Hmi materials with a highly developed surface and interconnected porosity were prepared by electrospinning (ES) from Hmi-containing feed solutions. Structural organization of the PHB/Hmi materials (porosity, uniform structure, diameter of fibers, surface area, distribution of Hmi within the PHB matrix, phase composition, etc.

Highly Sensitive Measurement of Horseradish Peroxidase Using Surface-Enhanced Raman Scattering of 2,3-Diaminophenazine.

The development of various enzyme-linked immunosorbent assays (ELISAs) coupled with surface-enhanced Raman scattering (SERS) detection is a growing area in analytical chemistry due to their potentially high sensitivity. A SERS-based ELISA with horseradish peroxidase (HRP) as an enzymatic label, an -phenylenediamine (oPD) substrate, and a 2,3-diaminophenazine (DAP) enzymatic product was one of the first examples of such a system. However, the full capabilities of this long-known approach have yet to be revealed.

Electrospinning of biomimetic materials with fibrinogen for effective early-stage wound healing.

Electrospun biomimetic materials based on polyester of natural origin poly-3-hudroxybutyrate (PHB) modified with hemin (Hmi) and fibrinogen (Fbg) represent a great interest and are potentially applicable in various fields. Here, we describe formulation of the new fibrous PHB-Fbg and PHB-Hmi-Fbg materials with complex structure for biomedical application. The average diameter of the fibers was 3.

Antioxidant role of methionine-containing intra- and extracellular proteins.

Significant evidence suggests that reversible oxidation of methionine residues provides a mechanism capable of scavenging reactive species, thus creating a cycle with catalytic efficiency to counteract or mitigate deleterious effects of ROS on other functionally important amino acid residues. Because of the absence of MSRs in the blood plasma, oxidation of methionines in extracellular proteins is effectively irreversible and, therefore, the ability of methionines to serve as interceptors of oxidant molecules without impairment of the structure and function of plasma proteins is still debatable. This review presents data on the oxidative modification of both intracellular and extracellular proteins that differ drastically in their spatial structures and functions indicating that the proteins contain antioxidant methionines/the oxidation of which does not affect (or has a minor effect) on their functional properties.

The effect of hypochlorite- and peroxide-induced oxidation of plasminogen on damage to the structure and biological activity.

In this study, we examined for the first time the effect of the HOCl/OCl- and HO-induced oxidation of Glu-plasminogen on damage to its primary structure and the biological activity of plasmin. The consolidated results obtained with the aid of MS/MS, electrophoresis, and colourimetry, demonstrated that none of the oxidised amino acid residues found in the proenzyme treated with 25 μM HOCl/OCl or 100 μM HO were functionally significant for plasminogen. However, the treatment of plasminogen with increasing concentrations of HOCl/OCl from 25 μM to 100 μM or HO from 100 μM to 300 μM promoted a partial loss in the activity of oxidised plasmin.

Hypochlorite-induced oxidation of fibrinogen: Effects on its thermal denaturation and fibrin structure.

Background: Human fibrinogen, which plays a key role in plasma haemostasis, is a highly vulnerable target for oxidants. Fibrinogen undergoes posttranslational modifications that can potentially disrupt protein structure and function.

Methods: For the first time, by differential scanning calorimetry, dynamic and elastic light scattering and confocal laser scanning microscopy, the consequences of HOCl/OCl-induced oxidation of fibrinogen on its thermal denaturation, molecular size distribution and fibrin clot network have been explored.

Simultaneous express immunoassay of multiple cardiac biomarkers with an automatic platform in human plasma.

C-reactive protein, cystatin C, myoglobin, and D-dimer represent the inflammatory or thromboembolic status of the patient and play important roles in early diagnostics of acute myocardial infarction. Each protein can indicate some health problems, but their simultaneous detection can be crucial for differential diagnostics. The express analysis of these proteins in a small drop of plasma was developed using magnetic beads.

The Structure of Blood Coagulation Factor XIII Is Adapted to Oxidation.

The blood coagulation factor XIII (FXIII) plays a critical role in supporting coagulation and fibrinolysis due to both the covalent crosslinking of fibrin polymers, rendering them resistant to plasmin lysis, and the crosslinking of fibrin to proteins of the fibrinolytic system. The hypochlorite-mediated oxidation of the blood coagulation factor XIII (FXIII) at the different stages of its enzymatic activation is studied for the first time in this paper. The consolidated results obtained with the aid of MS/MS, electrophoresis, and colorimetry demonstrate that in the process of FXIII's conversion into FXIIIa, the vulnerability of FXIII to hypochlorite-induced oxidation increased as follows: native FXIII < FXIII + Ca << FXIII + Ca/thrombin.

Ozone-induced damage of fibrinogen molecules: identification of oxidation sites by high-resolution mass spectrometry.

Fibrinogen is highly susceptible to oxidation compared to other plasma proteins. Fibrinogen oxidation damages its structure and affects the protein function. Ozone-induced oxidative modifications of the fibrinogen Aα, Bβ, and γ polypeptide chains upon addition of various amounts of the oxidiser were studied by mass spectrometry.

Oxidation-induced modifications of the catalytic subunits of plasma fibrin-stabilizing factor at the different stages of its activation identified by mass spectrometry.

Plasma fibrin-stabilizing factor (pFXIII) is a heterotetrameric proenzyme composed of two catalytic A subunits (FXIII-A) and two inhibitory/carrier B subunits (FXIII-B). The main function of the protein is the formation of cross-links between the polypeptide chains of the fibrin clot. The conversion of pFXIII into the enzymatic form FXIII-A* is a multistage process.

Oxidation of proteins: is it a programmed process?

Proteins represent extremely susceptible targets for oxidants. Oxidative modifications of proteins may bring about violation of their structure and functionality. It implies that the structures of proteins are not infallible in terms of their antioxidant defence.