فصلنامه تازه های بیوتکنولوژی سلولی مولکولی
پیاپی 45 (زمستان 1400)

Nanoparticles have a great impact in various fields of medicine and therapy, including biosensors, imaging and smart drug delivery. SARS-Covid 2 is a coating virus and has particle-like properties with a diameter of 140-160 nm. The synthesized nanoparticles are very similar to the virus and will easily interact with its proteins. Therefore, nanoparticle solutions, including antiviral mechanisms to prevent the growth, proliferation and penetration of the virus, the production of masks, vaccines, is a good option to combat the virus. Due to the impact and prevalence of the Covid-19 disease and its risks to the health of people around the world, after the first days of identifying the virus, researchers sought ways to diagnose the disease in individuals, as well as its prevention and treatment. So far, vaccination has been the best way to fight against the Covid-19. In the meantime, nanoparticles due to their special properties could have many uses, including diagnosis, vaccine and drug production. In this paper, we examine the implementations of nanoparticles against the Covid-19.

Brassica napus has one of the most important oilseed crops in the world, which has undergone extensive genome reconstruction following an interspecies hybridization of Brassica rapa and Brassica oleracea. In order to understand the functional changes of B. napus genome during the evolution, comparison of gene expression was performed in three species of Brassica.

Seed preliminary data of three Brassica libraries were collected from the Harvard university database. To find similarities between three libraries, all EST sequences were assembled using EGassembler software. Then, all contigs were analyzed by X-blast using CLC Protein workbench software against nonredundant proteins of gene bank. IDEG6 software was used to identify genes with different expression between libraries. MapMan comparative classification tool was used to classify functional catalogs.

Comparison of gene expression between the three species showed that 23 genes in 5 functional groups including fatty acids, storage proteins, amino acids, transcriptional regulation and signaling were statistically significant.

While B. rapa and B. oleracea encode the largest number of ESTs involved in the biosynthesis of erucic acid and linolenic acid, genome in B. napus has evolved to produce more oleic acid and linoleic acid, which may have resulted from the deletion or duplication of the genome during evolution. In addition, Cruciferin transcripts accounted for 40% of total seed storage protein transcripts. This study paves the way for further research on the genetic consequences of polyploidy during canola breeding evolution.

Klebsiella pneumoniae (K. pneumoniae) is one of the important human pathogens among which emergence of antibiotic resistant results in many problems in therapeutic process. Class 1 integron genes may facilitate the conferring of antibiotic resistance among bacterial population. In the present study, isolation of K. pneumoniae from urine samples, determining the antibiotic resistant pattern, and evaluating the presence of class 1 integron genes were investigated.

The obtained isolated bacteria were confirmed via biochemical tests. Evaluating the bacterial resistance against 10 different antibiotics was performed by agar disk diffusion method and antibiotic resistant pattern was also determined. PCR method was used in order to detect the presence of class 1 integron genes among isolates.

80 K. pneumoniae were isolated from the urine sample of attendees of clinical laboratories in Karaj. Meropenem and Nitrofurantoin were the most and least effective antibiotics, respectively. 16 isolates were considered as multi drug resistance (MDR) among which resistance to all 10 tested antibiotics was also observed. 29 isolates were also positive in terms of class 1 integron genes.

Treatment with the following antibiotics; Meropenem, Levofloxacin, Imipenem, and Gemtamicin, may be successful, since more than 80% of the isolates were susceptible to them. However, presence of MDR as well as detecting class 1 integron genes may be an alarming for infections caused by K. pneumoniae.

Knowing about the increase in the antibiotic resistance among K. pneumoniae isolates, the presence of MDR isolates, and also detecting the presence of genes involved in dissemination of resistant isolates may help to choose the more effective therapies.

Actinomycetes are a good resource to discover new drugs based on their abundant secondary metabolites. Because both fungal and human cells are eukaryotes, the metabolites of fungal antagonist actinomycetes may also inhibit the growth of cancer cells.

The antagonistic activity of 24 actinomycete strains that inhibited the growth of cells of a plant pathogen, Phytophthora capsici, was investigated against 4 other plant pathogens. The siderophores production of two selected strains that showed the highest antagonistic activity against pathogens was evaluated. The cytotoxicity effects of two strains on the SW480 cell line was measured using MTT assay in vitro and the IC50 percentage was determined.

Only two selected strains had 30 and 54% inhibitory effect against Phytophthora drechsleri, respectively. The strain 408 had no inhibitory effect against Pythium ultimum, while the strain 6010 completely prevented Pythium ultimum growth. The strain 6010, unlike the strain 408, controlled the growth of Rhizoctonia solani and Fusarium oxysporum pathogens about 70%. Only the strain 408 was able to produce siderophore. The significant effect of the treatment on colorectal cancer cells was observed at 2.47 and 2.71% (v/v) concentrations for both 408 and 6010 strains, respectively.

The results of this study confirmed our hypothesis that secondary metabolites of antagonistic actinomycetes can lead to cancer cells death. The use of fungal or oomycete cells is introduced as an easy, safe, and inexpensive method for screening actinomycetes that are candidates for the discovery of new anticancer drugs.

Salinity is one of the most important stresses that has affected food security. (Chenopodium quinoa) is a plant that is currently considered worldwide as a food substitute for wheat, rice, barley and corn. The aim of this study was to investigate the activity of antioxidants, some osmolites, ions and minerals to identify salinity resistant genotypes that can be grown by cultivating quinoa in hot and dry regions of the country that face temperature, drought and salinity stresses. This plant was used as food for humans and fodder for livestock.

In this study, physiological responses of 3 genotypes (Q18 ,Rosada ,Sajama) with relatively high yields were investigated at different levels of salinity stress (control (EC=1.5) and 8, 16, 32 dS/m) in greenhouse conditions and Plants were harvested in the twelfth week for morphophysiological and biochemical measurements and studies were performed on the plant.

By studying the results of Na+ content in salinity stress, it seems that Sajama and Rosada have more ability to prevent Na+ transfer from root to shoot and prevent K+ reduction, also the total amount of elements (Cu+2, Mn+2, Ca+2, Zn+2, Fe+2) decreased at salinity 32 dS/m. The results showed that comparing the growth parameters and increasing proline and decreasing the protein content at salinity 32 dS/m can be associated with reduction of chlorophyll, carotenoids, reduced sugars, total carbohydrates, increased oxidative stress and H2O2 content. However, total ascorbate and glutathione content remained constant at salinity 32 dS/m in Q18, but Sajama and Rosada decreased and phenylalanine ammonialyase activity increased in all genotypes and all salinity levels. Phenolic compounds, flavonoids and anthocyanins in genotyp Rosada showed a greater increase in salinity stress than the other two genotypes.

The total results showed according to the rate of reduction of growth parameters, genotype Sajama seems to be more tolerant of salt than the other two genotypes and the salinity tolerance of Rosada genotype is lower than the other two genotypes but there is no relationship between increased phenolic compounds, flavonoids and anthocyanins and salinity resistance in this genotype

 Cytomegalovirus (CMV) is a member of the herpesviridae family, which is a major cause of intrauterine viral infection. The aim of this study was to evaluate the diagnosis of CMV in women with idiopathic abortions by the polymerase chain reaction (PCR) technique.

 50 blood samples of women with idiopathic abortions were collected and viral genome was extracted using commercial kit DNG-Plus. The PCR technique was optimized using the standard CMV strain genome and then the Limit of Detection (LOD) and specificity of the test was evaluated using genomes other than CMV. The optimized PCR technique was performed on the samples and positive and negative controls and the results were analyzed by gel electrophoresis.

 using optimized PCR technique, 257bp product were observed in agarose gel. In the specificity test, positive results were obtained only with the CMV genome and a detection limit of 100 copies per reaction was obtained. Finally, out of 50 samples, two samples were positive for CMV.

 Idiopathic abortions are abortions that do not seem to have a specific cause. But obviously many factors including infectious agents that can cause abortion are difficult to identify them. One of these factors could be CMV and the results of this study showed that it is best to search and identify CMV in this type of abortion by molecular tests such as PCR, quickly.

The use of medical herbs because of their reasonable price and availability is rapidly increasing but it faces many challenges. Researchers are trying to overcome these challenges by designing nano-drug delivery carriers such as liposome. In this study, a formulation of liposomal system containing Hedera Helix extract was synthesized and its toxicity on normal cells and physicochemical characteristics were evaluated.

  In the first step, extraction of Hedera Helix was done by succulent method. In the next step, nano-liposomes were prepared by thin film method from phosphatidylcholine and cholesterol and by using hydration inactive method the extract was loaded into them. Then the encapsulation rate and the release pattern were assayed by spectrophotometry method, the size of nanoparticles and their zeta potential were evaluated by the DLS, the non-interaction between the extract and the nanosystem was assessed by FT-IR technique and the morphology of the nanoparticles was examined by AFM microscope and finally the non-toxicity of the system on normal cells was assayed by MTT method.

The results of this study showed that nano-liposomes containing Hedera Helix extract having 48.6 nm of diameter, 0.406 dispersion index, -37.3 ± 1.72 mV zeta potential and 82.67 ± 1.12 encapsulation efficiency are follow the slow releasing drug pattern. FTIR and AFM data demonstrated that there is no interaction between the extract and nanoliposomes and nanoliposomes have appropriate morphology. Finally, the results of the MTT assay confirmed the non-toxicity activity of nano-liposome.

In this study, physicochemical studies of nanosystems after loading Hedera Helix extract into liposomal nanosystems showed that the system is a slow-release and anionic type with acceptable size, morphology and acceptable encapsulation rate. The synthesized liposomes could be a suitable carrier for the Hedera Helix extract and increase its stability, solubility and thus improve its therapeutic performance.

Enterokinase is a gastrointestinal enzyme that acts as a protease with a specific sequence. Due to the ability of enterokinase to enzymatically digest the recombinant protein at its specific site (including the four amino acids Aspartic acid and one amino acid lysine), which is targeted at the protein, as a very useful tool for purification and separation Target protein from the non-target part is used in the pharmaceutical, food and industrial industries.

Independent variables used included OD (0.6, 1.2 and 1.8) at 600 nm, IPTG concentration (0.2, 0.5 and 0.8 mM) and The type of bacterial strain was (ShuffleT7, BL21, NICO21). The response surface methodology (RSM) in the form of a central composite scheme was used to predict independent variables on the production of enterokinase enzyme.

OD equal to 1.8 at 600 nm wavelength, IPTG concentration of 0.71 mM and type of ShuffleT7 bacterial strain, LB culture medium, 2.5 mM lactose concentration and 25 ° C induction temperature, for production Recombinant enterokinase was optimized.
Discussion and

Drug proteins play an important role in modern molecular medicine therapies. Enterokinase gene expression in the bacterial system facilitates the purification of low concentrations, so large-scale, highly purified recombinant proteins can be produced and optimized in the bacterial system.