نشریه زیست فناوری دانشگاه تربیت مدرس
سال هشتم شماره 1 (پیاپی 14، بهار و تابستان 1396)

Water pollution is one of the most important problems for human beings. BTEX (Benzene, Toluene, Ethylbenzene and Xylenes) have vast application in industry and their carcinogenic effect on human body has approved. Hence these part of water pollutants (water-soluble aromatic components) have more importance. Monitoring systems that can detect presence of BTEX in water supplies are much expensive such as gas chromatography so we need simple systems to reduce the number of samples that we are suspected to them for more analysis by much more expensive systems. Bioreporters are a subgroup of biosensors which are using for sensing and monitoring some signals or reagents. A bioreporter is an organism like a bacteria or a plant that is genetically manipulated to have a promoter which is sensitive to a chemical or physical signal. Activation of the promoter In presense of the signal leads to product of the reporter gene which can be sensed or calculated by our laboratory supplies. A green fluorescent protein gene has been used as a reporter gene downstream of PtbuA1 as a BTEX sensitive promoter in Escherichia coli and its response to BTEX has been investigated in this study. Our results show our bioreporter can sense Toluene.The optimum time and temperature for the bioreporter is also defined.

In recent years a lot of researches have been carried out about sensitivity of the living organisms to magnetic fields and nanoparticles. Therefore, to evaluate the effect of the magnetic field and silver nanoparticles on photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids), proline, glycine betaine, soluble sugars and proteins, nitrate and nitrate reductase activity and protein electrophoresis pattern on Calendula officinalis L., in 2015 experiments were performed in the Department of Biology, University of Urmia. Seedlings were grown for 30 days in four treatments including: control, magnetic field with B = 3 mT for an hour per day, silver nanoparticles (50 ppm), and magnetic field (B = 3mT) plus silver nanoparticles (50 ppm). The results showed that plants treated with magnetic field, silver nanoparticles and magnetic field silver nanoparticles photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids) content, compatible solutions content such as proteins and soluble sugar, proline andglycine betaine and nitrate content and nitrate reductase activity were significantly (P

Butanol is a fuel blended more readily with gasoline and hydrocarbon products and contains higher heat value in comparison with ethanol. Clostridium acetobutylicum is able to produce considerable amount of butanol. Acetone and ethanol are other products of this strain. Simple models describing the production of these metabolites like Monod model are restricted to prognosticate intracellular processes. The mathematical expression of intracellular metabolites production is applied to optimize the production of the desired compound, especially, in metabolic engineering. In this study, the structured model of the metabolic pathway of Clostridium acetobutylicum was utilized to describe and to predict the dynamical variations of intracellular and extracellular metabolites. Mathematical equations were solved by SimBiology and results were compared with experimental data published in literature, which revealed an appropriate conformity. The effect of butyrate and acetate on the butanol production was investigated and results demonstrated the butanol production enhancement in the presence of these substances in the culture media. The butyrate presence in the media led to both increase of butanol concentration and decrease of time required to attain the maximum butanol production. The butanol concentration were 120.48 and 138.35 mM when the initial concentrations of acetate and butyrate were 100 and 0 mM, and 0 and 100 mM respectively .Due to the irreversible production reaction of acetone in the metabolic pathway, butanol production was not influenced by the acetone concentration, but its elimination from the cell pathway increased the butanol production.

MiRNAs are known as regulatory genes in eukaryotic genomes, regulating their target genes expression. Here, we have investigated five pathogen responsive miRNAs; tae-miR156, tae-miR159, tae-miR167, tae-miR171 and tae-miR393 expression pattern in wheat Taichung 29 cultivar between day 10 to 20th of the seedling life. Since plant seedlings are mostly used for plant-pathogene interaction analysis, this research was committed to analyze the expression pattern of these miRNAs independent of pathogenesis and in 10 to 20 days old seedlings. Plants were grown in soil in greenhouse condition, and 10, 11, 13, 17 and 20 days old seedlings were harvested for RNA extraction and cDNA synthesis. QRT-PCR analysis of candidate miRNAs expression indicated that, tae-miR156 and tae-miR159 expression level has been sharply increased between day 13th to 17th and then after, decreased to the minimum level before day 20th. On the other hand, tae-miR167, tae-miR171 and tae-miR393 expression level has been gradually increased since day 13th of the growth. These data suggest that day 13th to 17th of the wheat seedling life, is crucial period of life in terms of drastic physiological changes which are affected by miRNAs expression. Since majority of the target genes of these candidate miRNAs are not known yet, their expression alterations is only suggested to be consistent with the expression of some known target genes, belong to the signaling pathway like auxin signaling. Considering sequence conservation pattern of miRNA precursors, here we suggested functional miR*s for tae-miR156, tae-miR159, and tae-miR393.

Aspartic proteases (APs) (EC 3.4.23.X) catalyze the hydrolysis of peptide bonds, a reaction that is fundamental to many biological processes. All of the vertebrate and most of the fungal APs are synthesized as zymogens. Porcine pepsin (EC 3.4.23.1) belongs to the aspartic protease family. Pepsin is a gastric aspartic protease and one of the three principal protein degrading enzymes in the digestive system. Pepsin is an industrial enzyme in the food industry. In this study, thermal stability of pepsin investigated in the different concentrations of aluminium in presence and absence of organic solvents ) butanol, ethanol, 1,4-Butanediol and glycerol). Thermal stability of pepsin increased in the presence of aluminium and decreased in presence of organic solvents ) butanol, ethanol, 1,4-butanediol ) and unchanged in presence of glycerol .Thermal stability of pepsin increased in presence organic solvents with adding of aluminium to its absence. possibly aluminum ions through electrostatic and dative interactions with carboxylate groups of Aspartic acid and Glutamic acid residues are bonded to pepsin structure, and causing to condense enzyme structure which leading to increasing thermal stability of pepsin. Mechanism of increasing thermal stability of pepsin is unknown in presence of aluminium. Therefore, we can reduce the instability of pepsin in presence of organic solvents by Aluminium.

Uricase or urate oxidase is an enzyme that converts uric acid (with low solubility) to 5-hydroxyisourate and finally to allantoin. The possibility of developing some diseases like gout and kidney stones will be increased in high levels of uric acid. Thus, uricase can be used as drug enzyme to reduce uric acid levels in the blood. The low stability of proteins (such as drug enzymes) is a challenge in the use of them. There are several approaches such as use of additives for protein stabilization. In this study, E. Coli BL21 (DE3) was transformed by pET28a () vector carrying Aspergillus flavus uricase gene. The recombinant protein was expressed and then purified by a Ni-NTA agarose chromatography column. After purification, the thermal stability of the purified enzyme was evaluated and then it stabilized by additives. The results showed that enzyme is active and purified very well. Thermal stability results indicated that uricase maintains its stability up to 20°C and then loses its stability. The half-life of enzyme was 30minutes at 40 °. The results of enzyme stabilization by 20% (v/w) concentration of glucose and sorbitol as well as by 20 % (v/v) of glycerol showed that glucose had the most stabilization effect on the uricase among the additives. The stability (half life) of enzyme was increased more than two times in the presence of glucose. Finally, we conclude that additives like glucose which increase surface tension have the most stabilization effect on the uricase enzyme stability.

Due to the wide applications of gold nanoparticles, there have been great demands for their synthesis recently. Chemical methods produce pure and Non-dispersive nanoparticles, but these are quite expensive and potentially toxic to the environment. It has been suggested that the use of biological organisms and their components could be a suitable alternative for the production of nanoparticle in an eco-friendly manner (green synthesis). Using plant extracts for nanoparticle synthesis can be advantageous over other biological processes because it eliminates the elaborate process of maintaining cell cultures and can also be suitably scaled up for large-scale synthesis. In this study leaf extracts of Water cress, were used for green synthesis of gold nanoparticles. Gold nanoparticles were formed by treating an aqueous HAuCl4 solution by different amount of plant leaf extract as reducing agent at different temperatures. UV–visible spectroscopy was used for monitoring of the reaction progress. The synthesized gold nanoparticles were characterized with Dynamic light scattering (DLS) size analyzer, Transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). The results show that only a few minutes were required for the synthesis of gold nanoparticles at 60 °C and 80 °C by 1000 μl of plant extract, suggesting appropriate reaction rates in comparable to those of nanoparticle synthesis by chemical methods. TEM images showed that spherical nanoparticles (size, 10–50 nm) were obtained at higher temperatures and leaf broth concentrations. The analysis of FTIR bands show that the Polysaccharides and proteins are probably involved in the bio reduction and synthesis of nanoparticles.

Aims: Basillus anthrasis is the causative agent of anthrax that can form the highly resilient spore. Because of this attribute, it is suitable to use as biological weapon and considered as a dangerous biological bioterrorism agent. The aim of this study is to predict an inhibitor of anthrax toxin receptor on human cells by using bioinformatics tools.
The interaction between anthrax toxin receptor and 57 herbal compounds were studied by using Swissdock webserver. Then the amino acids involved in the strong interactions, were obtained by UCSF Chimera software.
According to the results of this study, among the investigated compounds, 10 compounds include: Asarone, Bisabolol, Chlorogenic acid, Geraniol, Harmine, Harmaline, Sulforaphane, Fluphenazine, L-catechin and D-catechin are capable of inhibiting anthrax toxin receptor. That sulforaphane is probably the most effective inhibitor.
Results derived from processed analyses offer laboratory researches based on these compounds to produce an effective drug against anthrax toxin.

Microorganisms and plants have high potential for reducing the metal (biosynthesis of nanoparticles) through their metabolic pathways. Apart from the environmental benefits of biosynthesis of nanoparticles, there is the opportunity for production of nanomaterial with new properties in this method. In this study, the fruit aqueous extract of Capparis spinosa L. was used for synthesis of nanoparticles. To evaluate the reducing potential of plant, total phenolic content and antioxidant activities of both aqueous and ethanolic extracts were measured by DPPH and FRAP methods. The aqueous extract showed a lower antioxidant activity than the ethanolic extract; however, it had high potential to reduce the free radicals and metal ions. After preparing the extract, for phytosynthesis of silver nanoparticles, 2 ml of extract was added to 4 ml of 1 mM silver nitrate. The extract was used as a reducing and stabilizing agents of the nanoparticles. The effect of determining parameters for optimizing synthesis of nanoparticles such as: pH of reaction, the amount of extract, concentration of metal ion and time of reaction were evaluated using Ultraviolent-Visible (UV-Vis) spectroscopy and Transmission Electron Microscopy (TEM) .The spectrum of Surface Plasmon Resonance (SPR) of silver nanoparticles showed the maximum absorbance at 415 nm. Fourier Transform Infrared (FT-IR) spectroscopy was used to identify the possible functional groups involved in the synthesis of silver nanoparticles. The Results showed that the nanoparticles were spherical shape and the size of them were about 8-12 nm.

Pertussis toxin (PT), the main virulence factor of Bordetella pertussis is a protein-based AB5-type exotoxin. Methods of pertussis toxin purification are not available exactly because of economic considerations by vaccine companies. The aim of this study was to setup and modify an in-house method for the PT purification based on affinity chromatography to develop acellular pertussis vaccine in future. B. pertussis and CHO cells were provided from Razi Institute (Karaj, Iran). The bacteria were grown in a 300L fermenter (44 h, 35o c, in B2 medium). The fermentation broth was clarified and concentrated by 0.45 µm membrane filter and 10 KDa molecular weight cut-off membrane respectively. Isolation of pertussis toxin was performed based on affinity chromatography by Fetuin Sepharose column. Immune dot blot test showed significant amounts of pertussis toxin qualitatively. The clustering of CHO- cells mono-layer were observed after first hour of applying the purified pertussis toxin and stopped after the twelfth hour. The average amount of extracted PT was 2.53 IU/ml± 0.43. Among the production procedure of whole cell pertussis vaccine, culture broth is discarded, whereas, results showed it was a suitable source for extraction of pertussis toxin. Finally examine other strains and bacterial culture methods to obtain desired pertussis toxin are recommended.

Genus Medicago belonged to family Fabaceae is one of the most important forage legumes. Annual species of this genus are indigenous to Mediterranean region and used for prevention of soil erosion, green manure and forage. In this research, genetic variability and classification of 14 annual medicago truncatula genotypes using ISSR markers was done. 9 out of 15 ISSR primers which possessed suitable polymorphism and amplification were used for fingerprinting of studied genotypes. Totally, 71 bands were amplified via ISSR primers which 11 bands were monomorphic and 60 bands were polymorphic across genotypes. Based on Jaccard similarity coefficient, minimum similarity (0.25) was seen between TN8.3 (Tunisia) and TN6.18 (Tunisia) and maximum similarity (0.82) was seen between TN8.3 (Tunisia) and SA28064 (Cyprus). Population structure analysis using STRUCTURE software subdivided them into 9 subpopulation. In this study, maximum admixture was occurred in TN1.21 (Tunisia), A10 (Australia), F83005-5 (France), SA22322 (Syria), A20 (Australia), and DZA315-16 (Algeria) genotypes. Results revealed that annual self-pollinated M. truncatula had noticeable genetic variation which Is accurately detectable using ISSR molecular markers.

Negative sence RNA genome of Influenza A virus contains 8 segments coding for 12-14 proteins depending on strains. Genetically modified virus is caused world wide spread of a new Influenza in the human population. Developing a rapid and accurate diagnostic method to identify new species is necessary. The aim of this study was rapid detection of new species of Influenza A subtypes using specific RT-PCR based on hemagglutinin gene.
In this study 30 Nasopharynx samples of patient cultured in embryonated eggs. Then RNA was extracted, cDNA prepared and PCR was performed using specific primers designed from hemagglutinin gene. PCR products purified and sequenced.
Findings: PCR products sequences compared with Influenza A sequences obtained from the Gene Bank database. All positive isolates most closely related to the influenza reference strain. This Result showed that the specific RT-PCR used was able to amplified and detect Influenza A subtypes from clinical specimen.
The results of this study confirmed that PCR based on hemagglutinin gene with sequencing is a sensitive and accurate method for rapid detection of influenza A new subtypes directly from clinical specimen which is useful in preparation and production of vaccine.