Somayeh Farahmand; Faezeh Fatemi; Marzieh Dehghan Shasaltaneh; Reza Haji Hosseini; Shahriar Saeedyan
Abstract
In Acidithiobacillus ferrooxidans, proteins, like CoxB, present in the electron transmission pathway. The structure of CoxB has two copper atoms (CuA, CuB). CuA plays an important role in electron transport. According to previous studies, the conversion of histidine to methionine in a similar protein ...
Read More
In Acidithiobacillus ferrooxidans, proteins, like CoxB, present in the electron transmission pathway. The structure of CoxB has two copper atoms (CuA, CuB). CuA plays an important role in electron transport. According to previous studies, the conversion of histidine to methionine in a similar protein leads to an increase the stability of protein and to improve its function. Also, the binding of methionine to CuB in the wild protein structure is another reason for the selection of the H230M mutation in CuA site. Wild-type and H230M mutants are simulated in the presence of a bilayer membrane POPC using the gromacs version 5.1.4. The conformational changes of mutated protein were investigated by RMSD, RMSF, SASA, Rg, DSSP, density, MSD, thickness, PCA, ED, DCCM and FEL analysis. The results of the wild protein and H230M mutant analysis show that the bacteria still preserves its sustainability after mutation. It seems that the H230M mutation leads to the increase of the amount of electron reception that requires further studies in this regard. Molecular dynamic simulation and principal component analysis provide compelling evidence that this H230M mutation contributes to increase the stability of protein. Thus, this finding defines new approaches in structural properties, accurate survey, and probability improves the electron transfer.
Faezeh fatemi; Reza Hajihosseini; Abbas Golbodagh; abolfazl dadkhah
Abstract
Abstract Sepsis is the most common reason of mortality among patients who are in the intensive care unit. Regarding to the side effects of the anti-inflammatory drug consumption, the replace of natural products are suggested in sepsis treatment. the effects of the combination of the deuterium depleted ...
Read More
Abstract Sepsis is the most common reason of mortality among patients who are in the intensive care unit. Regarding to the side effects of the anti-inflammatory drug consumption, the replace of natural products are suggested in sepsis treatment. the effects of the combination of the deuterium depleted water (DDW) and Rosa (R.) damascena Mill. on the stress oxidative parameters and the gene expression of cyclooxygenase-2 (COX-2) in the lung and plasma tissues were investigated. 50 Rats were randomly divided into 5 groups: negative control (LAP), control group (CLP), two treatment groups with the combination of DDW and R. damascena Mill. essential oil (DDW15+EO and DDW30+EO) and positive control group with indomethacin (IND). Then, the levels of oxidative stress parameters and the expression of COX-2 were estimated in plasma and lung tissue. The sepsis resulted in the decrease of ferric reducing antioxidant power (FRAP) and glutathione (GSH) levels along with the increase of lipid peroxidation (LP) andCOX-2 levels. However, the rats treated with the combination of deuterium depleted water and R. damascena Mill. essential oils as same as indomethacin were influenced on the regulation of those parameters through the evaluation of FRAP and GSH levels and the reduction of the LP level and COX-2 gene expression. The pathological studies confirmed the biochemical consequences as well. The results indicated that the oxidative damages were caused by sepsis, but the administration of the natural products such as deuterium depleted water and R. damascena Mill. essential oils could improve the injures due to the effectiveness of oxidative stress and antioxidants parameters.
Mahnaz Shojapour; , Faezeh Fatemi; Reza Haji Hosseini; Marzieh Dehghan Shasaltaneh
Abstract
Abstract Acidithiobacillus ferrooxidans (Af) is an acidophilic bacterium involved in the bioleaching process. Cytochrome c552 (Cyc1) is a periplasmic protein that has a key role in the electron transportation in the respiratory chain. The presence of both heme A and B in the Cyc1 structure and its role ...
Read More
Abstract Acidithiobacillus ferrooxidans (Af) is an acidophilic bacterium involved in the bioleaching process. Cytochrome c552 (Cyc1) is a periplasmic protein that has a key role in the electron transportation in the respiratory chain. The presence of both heme A and B in the Cyc1 structure and its role in taking electrons from the previous protein and electron transfer to the next protein is the main reason for choosing this protein. In this research, with purpose of improving the bioleaching process, glutamate 122 and histidine 54 Cyc1 were selected for point mutation in bioinformatics studies. Mutations were performed by PYMOL software and simulated molecular dynamics for wild proteins, and mutant E122D, H54I in Cyc1. The conformational changes of mutated protein were investigated by SASA, Rg, NH bond analysis. Our results confirmed that the mutated proteins retained its stability during the simulation. By converting glutamate to aspartate, an acid molecule changed into a more acidic molecule leading to the further decreased redox potential at the rusticyanin midpoint resulted into the improved electron transfer from the Rcy to Cyc1 . This will also cause the increased electron transfer rate to heme A. In the case of converting histidine 54 to isoleucine, an electrostatic imidazole loop changed into an amino acid with the root of R with lack of charge which leads to the formation of a stronger hydrogen bond between the two amino acids. Therefore, probably the electron transfers between Cyc1 and CcO is improved through a water molecule (W79) leading to increased bioleaching rate.
