مجله پژوهش های سلولی مولکولی (زیست شناسی ایران)
سال سی و پنجم شماره 3 (پاییز 1401)

Oxidative stress is a phenomenon that results from the overproduction of reactive oxygen species and has a destructive effect on the natural function of enzymes, body proteins, cells and even organs in an organism. Previous studies by many researchers have shown the use of natural and predominantly herbal compounds such as polyphenols, as a safe way to inhibit the destructive effects of oxidative stress. The non-enzymatic mechanism of action of these antioxidant compounds is mainly attributed to the hydroxyl groups attached to the benzene or aromatic rings through which hydrogen atoms are donated to free radicals, leading to the scavenging and neutralization of the negative effects of the reactive oxygen species. In this paper, the antioxidant strength of three polyphenolic compounds, including taxifolin, morin and curcumin has been studied at a relatively low concentration, using DPPH, a chemical compound as a free radical. The H4 ELISA fluorescence reader, Excel, OriginLab, Graph Pad Prism and ACD/ChemSketch softwares were used in this study. The results revealed that taxifolin had the highest antioxidant strength followed by curcumin and morin. Taxifolin's greatest antioxidant strength can be related to the presence of a number of hydroxyl groups attached to the phenolic rings, the oxygen atoms attached to the heterocyclic ring (C ring), and the spatial decoration of hydrogen atoms. In conclusion, the results from this study, emphasizes more than ever, on the consumption of nutritious plant products, such as citrus fruits and nuts, as well as the spices recommended in traditional medicine, such as turmeric.

There are crucial factors in the bioethanol production process that affect production efficiency. Accumulation of ethanol during the fermentation process and the inhibitory effect on growth are inevitable. Increasing ethanol tolerance in Saccharomyces cerevisiae enhances survival and ultimately increases ethanol production. The evolutionary engineering approach is a promising strategy to improve the complex trait of ethanol tolerance in the Saccharomyces cerevisiae. The toxicity mechanism of short-chain alcohols on yeast are similar. In this study, the laboratory strain of Saccharomyces cerevisiae CEN PK113-7D was exposed to 1-butanol stress by evolutionary engineering strategy during a 144-days culture period, after which the specific growth rate (µ) of the evolved strain was boosted from 0.48 h-1 to 0.84 h-1. Increased stress tolerance of 1-butanol led to an increase in ethanol tolerance and also ethanol production in the evolved strain. Ethanol production improved from 68.50 g/L in the parent strain to 87.02 g/L in the evolved strain. The results of the whole genome sequencing of evolved strains and comparing it with the parent strain sequence revealed changes in the single nucleotide polymorphism (SNPs) of the genes involved in this trait. There were changes in genes such as PGM2, MTH1, TCB1, YAP1801, UBP2, FAB1, IAH1 and CIA1. These genes were related to intracellular transport and pathways involved in cytoplasmic membrane composition and structure, cell wall structure, glucose metabolism, and lipids metabolism. So, the significance of this set of genes in the enhancement of ethanol tolerance was reported for the first time.

Drought is the most challenging abiotic stress, which has irreversible effects on plant growth and development and reduces crop production worldwide. The effects of drought stress on the structure of leaves, roots, and stems of Tritichum aestivum cv. Mihan, were investigated under four different irrigation levels i.e. optimal irrigation or 100% of field capacity (FC), low stress (75% FC), mild stress (50% FC), and severe stress (25% FC). Microscopic sections from plant tissues were prepared, stained with Carmen Zaji and Methylene Blue, and studied using fluorescence and light microscopy. The results showed that in the roots, drought stress reduced the thickness of sclerenchyma tissue, cell walls and casparian strip in the endodermis, as well as the diameter of the root and metaxylems and the number of metaxylems. However, the lignin of the root's epidermal cell walls was increased. In stems, drought stress reduced the thickness of the cuticle layer and as well as cell walls diameter of sclerenchyma tissue, xylem and phloem. Reducing of chlorenchyma tissue area and ground parenchyma tissue cell size were also seen. In leaves, an increase in epidermal cell size, anthocyanin content, sclerenchyma cell size, and a decrease in xylem diameter were observed. Taking all together, structural changes indicate plant's effort to adapt to drought stress, possibly through metabolic processes.

Biofilm is an accumulation of bacteria that increase binding to biological and non-biological levels and causes pathogenicity and infection in Staphylococcus aureus. The icaABCD operon genes are involved. The icaD gene plays an important role in the maximal expression of the enzyme N-acetylglucosamine transferase and leads to the phenotypic expression of extracellular polysaccharide in S. aureus. In this study, based on antibiogram test, the antimicrobial effect of ginger and artichoke extract on two strains of S. aureus was studied. Also, in the studied strains, after the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests, using real time PCR technique, the expression of icaD biofilm gene under the treatment of artichoke and ginger extracts was evaluated. The results of disk diffusion test showed that the concentration of 100 mg/ml of ginger and artichoke extracts in the standard and the pathogen strains of Staphylococcus aureus, create a inhibition zone of 15 mm and about 9 mm, respectively. MIC test also showed that the studied strains can grow at a concentration of 5000 µg/ml of plant extracts. The results of icaD gene expression under the influence of artichoke and ginger extracts in the standard strain showed an increase in the expression of this gene. However, in the pathogen strain of Staphylococcus aureus, ginger and artichoke extracts led to a significant reduction (P

Filoviruses are filamentous and enveloped particles posing a single‐stranded negative sense RNA genome. The filoviridae family including Marburgvirus and Ebolavirus cause acute and deadly hemorrhagic fevers since they are transmitted to human. So, filoviruses are considered as a serious and dangerous threat to public health. In recent years, bats have become increasingly known as potential reservoirs for several viral infections. Bats are widely distributed in all continents except the polar regions and a few ocean islands. The nature of their diet is varied from insects and animals, and plants. The diversity of bat species and some of their unique biological and ecological characteristics make it possible for hosts with a number of important viral infectious agents in medicine such as Marburgvirus, Ebolavirus, and Coronavirus. The present review study was focused on phylogenetic assessment and cytopathogenesis of filoviruses and Baltimore's groups VI & VII retroviruses transmitted from bat to human.

Various mutations in factor VIII locus are led to an X-linked bleeding disorder in hemophilia A. One of the leading causes of inefficient remedy for hemophilia A disease is the lack of specific and sensitive procedure for punctual diagnosis of the disease. miRNAs indicate that they have a great potential as diagnostic and prognostic biomarkers due to their stability in body fluids and their capability to identification. Furthermore, a relationship between alteration in expression levels of miRNAs and onset and progression of the hemophilia A disease has been reported.Prediction of new miRNAs and nomination as regulators of FVIII gene has been considered as the objective of this study. The ability to express new miRNAs in FVIII locus was studied via reliable bioinformatic databases such as SSCprofiler, RNAfold, miREval, FOMmiR, MaturBayes, miRFIND, UCSC genome browser, Deep Sequencing, and miRBase. Output data of previously mentioned databases were analyzed, and one stem-loop structure was qualified, and the region is predicted to express new miRNA. The presented stem-loop structure can be used as biomarker in diagnosis of the disease and regulation of factor VIII gene after subsequent experimental verification.

Because of the increasing growth of pollutants in the environment, in order to determine the destructive effect of heavy metals on chromosomes, the root tips of the flowering plants are used. Golpar (Heracleum persicum Desf. Ex fisch) belonging to Apiaceae, has the nutrition values and medical importance. The aim of present study is reveal the comparative toxic impact of lead, copper and zinc on the mitotic cell of root tips of Golpar. So the root tips of H. persicum, were treated with graded concentrations (viz. 50, 100, 150 and 200 ppm) of lead, copper and zinc. This is the first report of heavy metals on Heracleum persicum. The mitotic index and total abnormality percentage were calculated based on achieved data. Data shows that heavy metals concentrations, significantly lead to the decrease mitotic index by prevented root tips cells entering cell division phases. Mitotic abnormalities in the root tips cells have shown a concentration-dependent increase at different concentration in all treated sets. Mitotic abnormalities include sticky chromosome, micronucleus, laggard chromosome, bridge and precocious movement. The results of the present investigation indicated that lead, copper and zinc have genotoxic effects especially at higher concentrations. The ability of genotoxicity in the three studied elements is reduced from lead to copper and zinc, respectively. Due to the nutritional and medicinal importance of Golpar, the result of this study should be considered as a warning for the toxic effects of environmental pollutants on plants and even human health.

Biodemulsifiers are a group of biosurfactants with emulsion breaking ability and their most important application is separation of water from crude oil. These compounds can be a good substitute for chemical demulsifiers, due to their biocompatibility. The aim of this study was to isolate biodemulsifier producing bacteria and evaluate their performance in demulsifying water in oil emulsions. For this purpose, after sampling, bacterial isolation was made in modified mineral salt medium and purified on Mueller-Hinton agar. The production of biosurfactant was evaluated through hemolytic activity assay, drop collapse test, oil spreading test and cell hydrophobicity measurements based on microbial adhesion to hydrocarbons. The biodemulsifier activity of these compounds and their position in the cells were investigated by examining the demulsification ratio of water in kerosene emulsions in demulsification tests. Based on staining and biochemical and enzymatic tests, these isolates were identified as Bacillus sp. HS9, Staphylococcus sp. HS10, Bacillus sp. HS11, Bacillus sp. HS12. The demulsification activity of these isolates in breaking water in kerosene emulsions were 25 ± 3, 28.5 ± 5, 27.14 ± 1, 51.57 ± 1 percent, respectively. Among these isolates, Bacillus sp. HS12 with 51.57 ± 1 percentage of demulsification activity was selected as the preferred isolate. With regard to demulsification potential of these isolates, it is suggested that their performance be evaluated in crude petroleum and desalting units conditions in order to be applied in enhanced oil recovery and breaking undesirable emulsions in upstream facilities.

In this study, induction of death autophagy in the presence of quercetin was investigated in MCF-7 cells. At first, the effective dose of quercetin, resulting in 50 percent death in cellular population (LC50), was determined as 220 M using MTT assay. Ascertaining of the main type of cellular death was carried out using flow cytometry and its usual probes including Annexin-FITC and PI. Accordingly, the main type of cellular death mechanism in quercetin treatment was apoptosis with total percent value of 54%.Determination of effective mechanisms for cell death induction was performed using real time RT-PCR. Selected apoptotic genes in this study were p53, Bax, Bcl-2, Casp-3. Significant decrease in Bcl-2 expression, with respect to its anti-apoptotic effects, showed that the breast cancer cells were being sensitized for apoptosis in the presence of quercetin. Increasing the Bax/Bcl-2 ratio shows that, despite of the constant expression of Bax gene, the increased sensitivity of the cells for apoptosis is occurred via decreasing of the expression level of Bcl-2 gene. Study of quercetin effects for autophagy induction was carried out after nominating of mTOR, LC3, Beclin1 and DRAM genes and analysing their expression variations in the presence of quercetin. Decreased expression of mTOR alongside rigorous increase in LC3 expression totally supports autophagy induction. This notion was also confirmed by LC3II antibody and immunocytochemistry investigations. Our results showed that quercetin is able to induce death autophagy to kill breast cancer cells.

The alfalfa (Medicago sativa) plant was collected from the area of Andimeshk and in the spring of 2018. To express the 16S rDNA gene, the isolated bacteria were cultured in YMA environment under aerobic conditions and at a temperature of 25-28 °c. Genomic DNA localization was performed using the DNA extraction kit of SINA Gene Co. General and complete primers of sinobium bacteria were extracted from the NCBI site based on 16s rRNA gene sequences, and were used in sequencing the isolated bacteria genes in this study. The sequencing obtained by using Chromas Pro software was edited and compared using blasting software in NCBI database of three strains of alpha-alpha (Medicago sativa) were isolated and identified. The microscopic and macroscopic studies of the bacteria were identified. Bacterium 1 was identified as Gram-negative and caused by cream and embossed colonies, the second Gram-negative bacteria, with red-colored colonies and third bacterial colony isolated from the genus Alfalfa (Medicago sativa) plant. Sequencing results of 16S rRNA strains isolated from the Rhizoum species (Sequence ID = CP 021215.1) Sinorhizobium Meliloti (bacter1) (overlapping percentages 97 and game chats 2 percent), the second bacterium Sequence ID = CP-000738.1)) Sinorhizobium Medicae (bacteria 2) (the overlap percentage of 97 and 2-percent game chats) and third bacteria (Sequence ID = DQ-145546.1) Sinorhizobium meliloti (overlapping percentages 04.96 and 4% game chats) were identified.

In biology considering identification of sequencing of macromolecules, different techniques such as Electrophoresis agarose gel is used after separation from different cells. Ethidium Bromide is one the materials for coloring these gels throughout the world due to it’s low price comparing to other materials. In last years, extensive use of his material in biology and medicine labs and due to it’s solubility and persistency in water, natural ecosystems contamination has became an important issue. Entering the human body can lead to enhanced cancer incidence by disturbance of blood circulatory system, activation of different tissues and modulation of translation and transcription of DNA process. Several physical and chemical methods has been suggested for neutralization of Ethidium Bromide inducing BDD electrode, TiO2, activated carbon adsorption and etc. which nearly all of these methods have not been used extensively by investigators due to high price and complex procedures. Fenton’s oxidation is one of materials for neutralization of unfavorable chemical compounds and this material has not been studied for neutralization of Ethidium Bromide. Due to high utilization of Ethidium Bromide in labs, the aim of this study was to investigate the potential effect of different levels of two chemical materials Feso4 and H2O2 for neutralization of Ethidium Bromide. 6 treatments including different levels of Feso4 and H2O2 were investigated. The treatment containing 200 Mg / liter of Feso4 along with 300 Mg / liter H2O2 had the most potential for neutralization of Ethidium Bromide comparing to other treatments.

Since the introduction of L-dopa (3, 4-dihydroxylphenyl-L-alanine) in the 1960s, L-dopa has been recognized as a gold-standard medical therapy for Parkinson’s disease. In the present work, a newly tyrosine-transforming strain of Paenibacillus sp. CT4W was used for the biotransformation of L-tyrosine to L-DOPA. The process parameters were optimized using single- factor experiments and Taguchi design methodology under resting cell strategy. Based on the values obtained in single-factor experiments, the optimum parameters for L- DOPA production: cell mass 6g/l, Cu+2 0.045 g/l, Temperature 30º C, pH 7, agitation 150 rpm and 0.5 g/l of yeast extract as cosubstrate. The maximum yield achieved with these parameters was 0.29 g/l after 16 h incubation. A Taguchi L16 orthogonal array was subsequently employed for further optimization. The biotransformation reaction having 5 g/l cell mass, 1.5 g/l tyrosine and 0.03 g/l Cu+2 was found to be optimum for maximum L-DOPA production. Under the optimized conditions, resting cells of Paenibacillus sp. CT4W produced 0.96 g/l L-DOPA, with a molar yield of 53.5 % after 20 h incubation.