Molecular analysis of maize cystatin expression as fusion product in Escherichia coli.

Nowadays, plant cysteine proteinase inhibitors "namely phytocystatins" have attracted researchers towards the identification of their molecular structures and novel physiological functions. Their important roles in plant developmental processes and different stress responses have been well known. In spite of advances in the understanding of phytocystatins, we lack enough data concerning their heterologous expression especially in the forms of fusion products that are most important whether for biochemical, pharmacological or clinical studies.

DUF538 protein super family is predicted to be the potential homologue of bactericidal/permeability-increasing protein in plant system.

DUF538 protein super family includes a number of plant proteins that their role is not yet clear. These proteins have been frequently reported to be expressed in plants under various stressful stimuli such as bacteria and elicitors. In order to further understand about this protein family we utilized bioinformatics tools to analyze its structure in details.

Comparative fusion expression of maize SINAT5 in two different strains of Escherichia coli.

SINAT5 is a plant E3 ligase that regulates auxin signaling and root morphogenesis by ubiquitination of the NAC1 protein. Consequently, it may be a putative regulator of aspects of plant development cycles that are controlled by auxin. Efficient production, purification and correctly folded form of this protein are important requirements for functional studies.

The role of electron-transfer and H-atom donation on the superb antioxidant activity and free radical reaction of curcumin.

Antioxidant activity of curcumin has been thoroughly studied to declare the conflicting conclusions about the site of curcumin reactivity and the reaction mechanisms in ROS scavenging. Data confirmed that the antioxidant activity of curcumin's enol isomer (CurE) is not only higher than keto isomer (CurK) but also more than trolox. We found that two phenolic OH play a major role in the antioxidant activity for the both of CurE and CurK tautomers.

Proton-coupled electron-transfer mechanism for the radical scavenging activity of cardiovascular drug dipyridamole.

Dipyridamole (DIP) is a well-known pharmaceutical drug used as a coronary vasodilator and anti-platelet agent in clinics for treating several cardiovascular diseases. Primarily, the therapeutic effects of the drug are attributed to its antioxidant potency. In this research, we aim to declare the unknown antioxidant mechanism of DIP as well as its potent chain-breaking antioxidant activity in polar aqueous medium inside the cells, using different experimental methods and theoretical quantum calculations.

Phylogenetic study of SIVcpz MT145 virus based on proteome and genome analysis.

Molecular phylogenetic studies were performed by the alignment of protein/nucleotide sequences of human/simian immunodeficiency virus (HIV/SIV), followed by the construction of phylograms according to maximum likelihood method. We aimed to investigate the evolutionary relationship of the recombinant SIVcpzMT145, to other well-known SIVcpz and HIV-1 viruses. Expectedly, MT145 follows the rule of feasible recombination occurrence in SIVcpz clade as to it consists several recombinations in different genome sites including gag, Pol, and Env region.

Functional fusion expression of sunflower multicystatin in E. coli and its comparison with a single domain cystatin.

Identification of the molecular structure and novel biophysiological functions of plant cystatins or phytocystatins is of great interest in the field of molecular biology. The important requirements for these are the efficient production, purification and correctly folded forms of these proteins. We report here the cloning, easy expression and characterization of a sunflower multicystatin (SMC) as a functional fusion protein in E.

Intracellular ROS protection efficiency and free radical-scavenging activity of curcumin.

Curcumin has many pharmaceutical applications, many of which arise from its potent antioxidant properties. The present research examined the antioxidant activities of curcumin in polar solvents by a comparative study using ESR, reduction of ferric iron in aqueous medium and intracellular ROS/toxicity assays. ESR data indicated that the steric hindrance among adjacent big size groups within a galvinoxyl molecule limited the curcumin to scavenge galvinoxyl radicals effectively, while curcumin showed a powerful capacity for scavenging intracellular smaller oxidative molecules such as H₂O₂, HO•, ROO•.

Over-expression, purification and functional characterization of Celosia ClpS as a fused protein in Escherichia coli.

A ClpS homologue from Celosia cristata was expressed as maltose-binding fusion protein under the control of strong inducible tac promoter of pMALc2X vector in TB 1 strain of Escherichia coli. SDS-PAGE analysis showed that fused ClpS is produced as about 63 kDa protein in recombinant bacteria. Expressed product was purified to homogeneity with a yield of about 31 mg/l of bacterial culture.

The mechanism of antioxidant activity of IRFI005 as a synthetic hydrophilic analogue of vitamin E.

Developing a rational strategy to control intracellular reactive oxygen species (ROS) requires understanding the mechanism of antioxidant activity. In this investigation the properties of a novel synthetic analog of vitamin E (IRFI005) with potent antioxidant activity are described. A mechanism is proposed for its efficient radical-scavenging effects.

Heterologous expression of stress-responsive DUF538 domain containing protein and its morpho-biochemical consequences.

As a usual response, plants induce/activate various proteins which are thought to be involved in defense mechanisms against the biotic and abiotic stresses they may be confronted with. The novel DUF538 domain containing proteins with unknown functions have been found to be induced/activated in response to different environmental stress stimuli in plants. In order to perform biochemical studies with these new plant stress-responsive proteins, a cDNA containing DUF538 domain was amplified from Celosia cristata full-length leaf expression library using a specific primer set.

Chaperone-like activity of alpha-cyclodextrin via hydrophobic nanocavity to protect native structure of ADH.

The chaperone action of alpha-cyclodextrin (alpha-CyD), based on providing beneficial microenvironment of hydrophobic nanocavity to form molecular complex with alcohol dehydrogenase (ADH) was examined by experimental and computational techniques. The results of UV-vis and dynamic light scattering (DLS) indicated that the chaperone-like activity of alpha-CyD depends on molecular complex formation between alpha-CyD and ADH, which caused to decrease the amount and size of polymerized molecules. Computational calculations of molecular dynamic (MD) simulations and blind docking (BD) demonstrated that alpha-CyD acts as an artificial chaperone because of its high affinity to the region of ADH's two chains interface.

Carborundum-dependent entrance of EcoRI restriction enzyme into plant cells and specific cleavage of genomic DNA.

In a basic research to determine the morpho-molecular interactions of plant tissues with EcoRI DNA restriction enzyme, it was demonstrated that this protein is capable of entering the sunflower and maize leaf cells using a plant tissue-abrading material and cleaving the genomic DNA at specific sites. This was inferred from the analysis of morphological patterns of EcoRI-treated leaf areas as well as using some molecular tests, including the cleavage pattern analysis of genomic DNA isolated from treated locations followed by ligation of cleaved fragments into EcoRI site of a DNA cloning vector system. The overall results indicated that the specific restriction of genomic DNA may happen following the entrance of EcoRI protein most likely into the nucleus of plant cells.

New model for polymerization of oligomeric alcohol dehydrogenases into nanoaggregates.

Polymerization and self-assembly of proteins into nanoaggregates of different sizes and morphologies (nanoensembles or nanofilaments) is a phenomenon that involved problems in various neurodegenerative diseases (medicine) and enzyme instability/inactivity (biotechnology). Thermal polymerization of horse liver alcohol dehydrogenase (dimeric) and yeast alcohol dehydrogenase (tetrameric), as biotechnological ADH representative enzymes, was evaluated for the development of a rational strategy to control aggregation. Constructed ADH nuclei, which grew to larger amorphous nanoaggregates, were prevented via high repulsion strain of the net charge values.

Molecular cloning and expression in Escherichia coli of an active fused Zea mays L. D-amino acid oxidase.

D-Amino acid oxidase (DAAO) is an FAD-dependent enzyme that metabolizes D-amino acids in microbes and animals. However, such ability has not been identified in plants so far. We predicted a complete DAAO coding sequence consisting of 1158 bp and encoding a protein of 386 amino acids.