Showing 58 results for Mic
Maryam Haddadi, Gholam Reza Ghezelbash,
Volume 7, Issue 1 (4-2020)
Abstract
Urease-producing bacteria can precipitate calcite nano-crystals by producing urease in the presence of urea and calcium. Calcite precipitation resulting from microbial activity is a process which causes cementation of soil particles in nature. The purpose of this study was to isolate urease-producing halophilic bacteria in order to precipitate calcite in saline soil. Natural samples, including soil and saline waters, were selected for this purpose. At First, halophilic bacteria were isolated by salt-containing TSB medium. Then, a selective medium containing phenol red and urea facilitated the isolation of urease-producing bacteria. Hydrolysis of urea by urease causes alkalization of the medium and the formation of pink halo around colonies. Finally, the best isolate was selected for further study by measuring the release of ammonium by the Nessler method. The ability or inability of isolates to produce calcite was investigated by culturing the isolates on sedimentary medium with different salt concentrations for 10 days. In total, 110 halophilic isolates were isolated, among which 58 isolates had the ability of urease production. The microscopic studies of colonies showed that only 6 isolates were able to produce crystals on precipitation medium. Isolate 6 was selected for further study and then analyzed by X-ray diffraction crystals on precipitation medium. Isolate 6 was selected for further study and then analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM) equipped with an energy dispersive X-ray (EDX) detector. Studies of urease activity showed that this strain released 20.86 mM ammonium after 18 hours. This bacterium was identified by biochemical and molecular analyses and the comparison of its 16S rRNA gene sequence showed 99.92% similarity with the similar gene sequence in Staphylococcus xylosus and then this sequence was submitted in NCBI database with the accession number MG655155. This isolate was able to produce calcite in free salt medium, with salinity up to 10%. Nowadays, many efforts have been made to produce environmental-friendly cements, and therefore, the use of urease-producing halophilic bacteria is an appropriate candidate for bio-cementing in saline environments.
Sepideh Piroozi, Farideh Attar, Mohsen Falahati–anbaran, Kazem Mehdigholi,
Volume 7, Issue 1 (4-2020)
Abstract
Pterocephalus (Caprifoliaceae) consists of 30 species worldwide, mainly distributed in the temperate regions of the northern hemisphere, of which 14 species were reported from Iran, including five endemic ones. In this study, 35 leaf-related traits and 30 peduncle-related traits were investigated by light microscopy of 15 samples from 11 Iranian species of Ptreocephalus. Our results showed that there were two types of midrib, six types of leaf indumentum and five types of peduncle indumentum. Crystalized calcium oxalate was observed in the leaves and peduncles of most species except in P. plumosus and P. brevis. The profiles of the peduncles were hexagonal, circular or elliptical. The vascular cylinder shape varied from circular to sinuate form. P. wendelboi, with a very different morphology as compared with other species, also exhibited different anatomical characters. The hexagonal sections of peduncle in P. ghahremanii and P. kurdicus and two samples of P. szovitsii were found to be very similar. However, the mentioned characters were found to be less informative or charachterisation of other species. In conclusion, the results showed that the anatomical characters of the leaves and peduncles might have some taxonomic importance in the identification of some species of the genus Pterocephalus.
Siamak Yari, Zahra Shojaie, Samaneh Khodabandehlu, Sepideh Saiedi,
Volume 7, Issue 2 (7-2020)
Abstract
Gentamicin (GM) is an antibiotic widely used against gram-negative infections. However, its clinical application is limited due to its nephrotoxicity. Oxidative stress plays an important role in the nephrotoxicity of gentamicin. Previous studies showed that Rosa canina L. (RC) fruits possess antioxidant, antimutagenic and anticarcinogenic effect. The aim of this study was to investigate the protective effect of RC on GM-induced nephrotoxicity in rats. Thirty male Wistar rats were divided into five groups and treated as follows: Group 1 (control group) was treated by the oral administration of 1 ml normal saline, Group 2 was treated by a 100 mg/Kg (B.W) dose of GM intraperitoneally, Group 3 was treated by oral administration of 200 mg/Kg (B.W) of RC followed by a 100 mg/Kg (B.W) dose of GM intraperitoneally, Group 4 was treated by oral administration of 400 mg/Kg (B.W) RC followed by a 100 mg/Kg (B.W) of GM intraperitoneally, and Group 5 was treated by oral administration of 400 mg/Kg (B.W) of RC. The nephrotoxicity observed in each group was histopathologically evaluated by light microscopy and biochemically evaluated by measuring the levels of creatinine and urea in the blood serum. The relative weight of kidney in each gentamicin-treated animals in the group 2 was increased in comparison with those in the control group (p<0.05), however, the administration of RC extract decreased the kidney somatic index toward the normal level. While the animals treated with gentamicin showed significantly higher levels of serum urea and creatinine (p<0.001), simultaneous coadministration of GM with a high dose of RC (400 mg/Kg (B.W) ameliorated the biochemical indices of nephrotoxicity, showing the significant decrease in the levels of serum creatinine and urea. In addition, Histomorphological examination showed that the rats treated with GM suffered necrosis and desquamation of tubular epithelial cells, glomerular stasis and inflammatory cell infiltration in renal cortex, while simultaneous administration of RC and GM reduced those histologically damages. It could be concluded that the administration of RC showed a protective effect on the rat kidney by preventing renal damages induced by GM, therefore, the RC-based supplements could be proposed to minimize the GM-induced renal damages.
Seyedeh Zahra Mousavi Parsaii, Jamil Vaezi, Hamid Ejtehadi, Farshid Memariani, Mohammad Reza Joharchi,
Volume 7, Issue 4 (12-2020)
Abstract
Phelipanche pouyanii is described here as a new species from South Khorassan Province, East of Iran. Its diagnostic morphological features are the calyx teeth being far longer than the calyx tube and staminal filaments being glabrous. These characters clearly differentiated the new species from its closely related taxa, i.e., P. mutelii, P. angustelaciniata and P. nana. Results obtained from the pollen and seed micromorphological characters showed no significant taxonomic value in the delimitation of the new species from its closely related species. The internal transcribed spacer (ITS) sequences, however, showed sufficient differences to delineate the new species from its closely related species.
Fatemeh Daemi, Farideh Attar, Asghar Zamani, Mehrshid Riahi,
Volume 7, Issue 4 (12-2020)
Abstract
In the present study, seed surface ornamentations in 31 species (34 populations) and the capsule surface sculpturing in five species of the genus Scrophularia L. distributed in Iran were examined using Scanning Electronic Microscopy. Based on the published seed surface terminologies, all examined seeds show the reticulate pattern with scalariform inner ornamentations. However, there is enough but untrustworthy variations in epidermal cell shapes and the walls’ characteristics to divide the seed surface sculpturing patterns into four different groups: (1) cells with completely irregular shape; (2) cells without distinct shape so that their boundaries are not clear; (3) reticulate polygonal cells bordered with distinct walls neither undulate nor vesiculate, divided in two subgroups; forming elongated narrow cells and wide cells; (4) reticulate polygonal cells bordered with undulated or sometimes vesiculate walls divided in two subgroups; forming elongated narrow cells and wide cells. In addition, all the species' seeds can be alveolate, ridged or without distinct alveoli or ridges regarding their surfaces. There have also been variations in size, shape and color of the seeds even in a single individual. There are no applicable features of capsule surface sculpturing analyzed here, based on which species could be classified in certain groups.
Mehrdad Ghiasvand, Ali Makhdoumi, Maryam Moghaddam Matin, Jamil Vaezi,
Volume 8, Issue 2 (7-2021)
Abstract
Regarding the rising rate of esophageal cancer in some parts of Asia, including northern and northeastern regions of Iran, the identification of new anti-cancer compounds is essential to combat the disease. The relation between some plants metabolites and these endophytic microorganisms are well characterized. In the current study, the potentials of Ephedra endophyte bacteria for the inhibition of esophageal cancer cell line (KYSE-30) proliferation were investigated. A total of 54 endophyte bacteria (out of 70) were obtained from the sterilized surfaces of two medicinal plants, i.e., Ephedra intermedia and Ephedra foliata. Bacterial strains were then cultured in Tryptic soy broth (TSB) medium and, after 72 h incubation, the produced secondary metabolites were extracted by chloroform. Anticancer effects of secondary metabolites from theses bacteria on esophageal cancer cell line KYSE-30 were evaluated after 24, 48 and 72 h by MTT method. MTT assay results showed that only strain A1 had a cytotoxic effect on KYSE-30 cells. The IC50 amounts of this strain against KYSE-30 cell lines were equaled (µg/ml) to 346.4, 192.8 and 121.3 after 24, 48, and 72 hours, respectively. The molecular identification of strain A1 revealed that Microbacterium maritypicum (99.8% similarity) was the closest identified taxon to the strain studied. According to the promising ability of strain A1 to inhibit the growth of KYSE-30 cell line, the use of natural compounds produced by this bacterium to treat esophageal cancer was found to be applicable. However, more experiments are needed to confirm these results after purifying the ingredients, as well as conducting studies in animal cancer models.
Mozhgan Veisi, Fahimeh Koohdar, Masoud Sheidai,
Volume 8, Issue 3 (10-2021)
Abstract
Tamarix is the largest genus in the family Tamaricaceae with about 54 species. T. tetragyna var. meyeri and T. tetragyna var. deserti were previously reported from Iran. Due to the presence of overlapping features in the previously designed identification keys for the separation of these two varieties, it could be helpful to use other characters and character states derived from other sources, such as anatomical and molecular studies, in addition to find more effective morphological features for the separation of the two varieties. Therefore, the present study aimed to differentiate these two presumed varieties by multiple approaches using morphological, anatomical and molecular data. For morphological study, 6 quantitative and qualitative characters were examined in 12 samples of the two varieties. ANOVA analysis showed a significant difference between the studied characters. For anatomical study, 10 traits were examined in 4 samples of the two varieties, which also showed a significant difference. AMOVA analysis based on molecular studies using Scot marker showed a significant difference between the two varieties. The PCA biplot show the most variable traits in morphological and anatomical studies. For varieties delimitation, different clustering methods were drawn in all three studies. The results of this study showed that the use of appropriate diagnostic traits in morphological and anatomical studies as well as the use of molecular markers can be effective in showing the separated boundaries of the two varieties studied.
Vida Tafakori,
Volume 8, Issue 4 (12-2021)
Abstract
The purpose of this study was to evaluate phytochemical characterizations and the in vitro antifungal capacity of the aqueous and methanolic extracts of the flower of Tulipa biflora Pall., against various yeast and mold species. For this purpose, fresh flowers were grinded and then macerated in methanol and water overnight, the resulted extracts were then evaluated by various tests. The results indicated that the extracts had different phytochemical components such as terpenoids, tannins, flavonoids, alkaloids, phenols, and phlobatannins. After the evaporation of solvents, antifungal activities of the concentrated extracts were evaluated by the well-diffusion method on Candida albicans, Trichosporon asahii, Yarrowia lipolytica, Aspergilus niger and Fusarium oxysporum. The results showed that the extracts were effective on yeasts and mold species studied except for Aspergilus niger. In order to determine the minimum inhibitory concentration (MIC) and minimum biocidal concentration (MBC) of the extracts, anti-microbial tests were performed in micro-plates. The methanolic extract had more antifungal effectsthan that in the aqueous extract. Therefore, the extract of Tulipa biflora could be introduced as a source for antifungal agents.
Hiba Zedan, Seyed Masoud Hosseini, Ali Mohammadi,
Volume 9, Issue 1 (3-2022)
Abstract
The aim of this study was to increase the shelf life of traditional yogurt, to improve its consistency and to prevent whey syneresis by adding tarragon essential oil. Yogurt was produced by industrial procedures and then the essential oil was inoculated into yogurt in different concentrations (10, 25, 30 ppm). Samples were examined for water storage capacity and microbial evaluation during 3 weeks of storage at two temperatures (refrigerator temperature and room temperature). The results showed that different concentrations of tarragon, temperature and storage time had a significant effect (p <0.05) on water holding capacity as well as the number of starter bacteria, molds, and yeasts. Tarragon essential oil reduced the number of bacteria, molds, and yeasts that spoil yogurt. The final results showed that the use of tarragon was not effective in water retention of yogurt samples, but it affected the number of initiator bacteria and yeast. Yogurt samples with high concentration of tarragon had the highest score in terms of consistency and sour taste. While samples with low concentration of tarragon, in terms of yogurt taste, had the highest sensory score.
Nasrin Farasat, Masoud Sheidai, Hossein Riahi, Fahimeh Koohdar,
Volume 9, Issue 3 (12-2022)
Abstract
The genus Ulva L. (Sea lettuce), one of the most valuable marine macroalgae, is found in shallow coastal areas and in brackish and fresh water around the world. Ulva species have nutritional and medicinal values in addition to other applications, and contain various compounds such as lipids, proteins and carotenoids. These species have high phenotypic plasticity and varied in response to different environmental conditions. In this study, 38 populations of 10 species of Ulva from the coastal areas of the Persian Gulf and Oman Sea, from different areas of Bushehr, Hormozgan and Sistan and Baluchestan provinces, were studied and identified on the basis of morphological and anatomical traits. Different populations showed variations in characteristics such as height, shape and color of thallus, number of pyrenoids and cell dimensions. Metabolites such as total protein, total oil, chlorophyll a, b and carotenoids contents were measured and compared among the different populations. The results should that the percentage of protein was highest in U. prolifera of Shif Island from Bushehr province as compared with the Ulva species studied, with about 26.5% of dry weight, and the percentage of total oil was lowest in U. flexuosa of Hakhamanesh region from Hormozgan province as compared with the species studied, with about 4.8% of dry weight. These results show that different environmental conditions affect the morphological and anatomical structure of species and the content of their metabolites. Due to the high-protein and low-calorie content of the Ulva genus and the importance of finding new and sustainable resources for food and pharmaceutical industries, the species of this genus have valuable potentials.
Raheleh Ahmadpour, Roya Ghalavand, Saeed Reza Hosseinzadeh, Nezam Armand,
Volume 9, Issue 4 (12-2022)
Abstract
Successful germination is the main factor in proper establishment and seedling yield. Information on seed germination, in the face of temperature changes at the time of planting, is a way to identify more suitable cultivars for cultivation at the planting site. For this purpose, a factorial experiment was performed based on completely randomized design with 3 replications. This experiment was conducted to investigate the temperature changes on the germination and growth indicators of lentil cultivars at Khatam Al-Anbia University of Behbahan. The studied treatments included five lentil cultivars of Gachsaran, Kimia, Robat, Ziba and Bilehsevar, and the temperature levels were 20, 25 and 30 °C, similar to the autumn conditions of Khuzestan Province. The results showed that all the seedlings of investigated cultivars cultivated at temperatures of 20 and 30 °C had a significant decrease in all the investigated traits, i.e., germination percent, germination rate, germination vigor, seed vigor index, endosperm consumption, plumule length, radicle length, seedling length, plumule dry weight and radicle dry weight, in comparison with those seedlings cultivated in 25 °C. The study of the interaction of cultivar-temperature effects showed that Bilehsevar cultivar had the highest germination and growth indices at 25°C compared to other investigated cultivars. This increase in traits such as germination rate, germination vigor, seed vigor index, plumule dry weight and radicle length was more significant in Bilehsevar cultivar compared to other cultivars. The second rank of the highest germination and growth indices was assigned to Gachsaran cultivar under 25°C conditions, which had a significant increase compared to other cultivars (Kimia, Robat and Ziba). Considering the autumn cultivation of lentils and the changes of temperature in that season (temperature range of 20 to 30 °C) in the studied area, the use of Bilehsevar and Gachsaran cultivars under the temperature of 25 °C, due to their higher germination indicators compared to the other cultivars, i.e., Ziba, Kimia and Robat, could be recommended.
Mehri Farzadi, Reza Khakvar, Abolghasem Mohammadi, Thomas Rattai,
Volume 9, Issue 4 (12-2022)
Abstract
Urmia Lake is the largest lake in the Iranian plateau and the second largest Salt Lake in the world. This study was conducted to identify hypersaline bacteria in the lake through the screening with molecular markers. For the molecular study of the bacterial microbiome of the lake, samples were collected from water, sludge and soil of the different parts of the lake during different seasons of 2018 and 2019, and then transferred to the laboratory under standard conditions. Bacterial isolates were purified from the samples using universal culture media. ERIC molecular marker was used to study the species diversity. After clustering analysis of the species on the basis of their genetic markers, one bacterium from each cluster was selected as the representative of each cluster and then identified by DNA barcoding method using the 16srDNA. Biochemical tests were performed to confirm the molecular results. In total, 102 bacterial isolates were isolated and purified from the samples, of which only 29 isolates were extremely-halophilic. The molecular diversity of isolates, based on ERIC molecular marker, showed that isolates can be assigned to five different clusters. Five isolates selected from each cluster were selected and their 16SrDNA region were amplified and sequenced with 16SrDNA-specific primers. The results showed that the five selected isolates with 99% similarity belonged to the species Microbulbifer halophilus, Halomonas salina, Bacillus sonorensis, Salinivibrio costicola and Bacillus aquimaris. The results of molecular identification were consistent with the results of biochemical tests.
Zeinab Mollaie, Leila Karami, Elham Rezaee, Gilda Karimi,
Volume 10, Issue 3 (12-2023)
Abstract
It has been found that the second isoform of COX enzyme known as COX-2 plays an important role in inflammation and rheumatoid arthritis and osteoarthritis. Thus, designing COX-2 inhibitors to treat inflammation is among the most important goals of researchers. In this study, the inhibitory effect of 3 new imidazole derivatives on COX-2 was evaluated by in silico approach. Molecular docking was done using Autodock Vina and the best binding mode of inhibitors was used as input of molecular dynamics (MD) simulation. MD was performed using Gromacs software for 120 ns. Then, structural and thermodynamic analyzes (ΔGbinding) and prediction of physicochemical properties were performed. RMSD data showed the compounds reached a good equilibrium and had favorable stability during simulation. Also, the RMSF showed that due to binding of inhibitors, the fluctuations of complexes decreased and the active site residues had the lowest amount. Rg, SASA and DSSP analysis showed that the protein structure did not change significantly. It was also found that Ser530 and Tyr355 residues play a more effective role in hydrogen bond formation. Physicochemical parameters determined the good drug-likeness properties for all compounds. Structural and thermodynamic analyzes (MM-PBSA) and IC50 data indicate the favorable inhibitory effect of compound 5b.
Atiqullah Sultani Ahmadzai, Hamid Ejtehadi, Mohammad Farzam, Maral Bashirzadeh, Farideh Attar, Mohammad Reza Joharchi,
Volume 10, Issue 3 (12-2023)
Abstract
The new species Onosma nuristanica is described and illustrated here on the basis of specimens collected from Parun in Nuristan and Chapa Dareh in Kunar, one of the eastern provinces of Afghanistan. An extensive review of the literature and a comparative study with specimens from several herbaria led to the determine of this new species. Our results represent significant divergence between studied specimens in terms of the most important morphological features, i.e., flower color, pedicel length, bract length filaments length, cauline shape and form. In this article, a detailed description of the new species and a diagnostic key for Onosma species thriving in Afghanistan are provided and the new species is compared morphologically with its closely related species. In addition, a distribution map is provided for the new species and its close relatives in the area.
Fatemeh Jafari, Ali Ganjeali, Elham Amjadi,
Volume 10, Issue 4 (12-2023)
Abstract
Nepeta binaludensis jamzad, as a medicinal plant, which is at risk of extinction due to irregular harvesting and damage of its habitat. Four treatments including: 1- inoculation with Azotobacter chooroccum, 2- inoculation with Bacillus cereus and Pseudomonas putida, 3- inoculation with a mix of three bacteria (A. chooroccum + B. cereus + P. putida) and 4 controls (without inoculation), in the form of a completely randomized design with 3 replications in two vegetative growth stages (ten and twenty weeks after sowing). Plant growth-promoting bacteria (PGPB) improved all the evaluated morphological characteristics, including the length and dry weight of the aerial part, total leaf area and root length compared to the control. Also, the results of biochemical investigations showed that in 10 and 20 weeks old plants, the application of PGPB could increase the phenolic and flavonoid compounds and also antioxidant activity. The contain of some elements such as calcium, potassium, phosphorus, iron and magnesium also increased as a result of inoculation with PGPB. Since the PGPB improved the growth and also increased the effective compounds of N. binaludensis plants, they can be introduced as useful bio fertilizers and considered as a good alternative to chemical fertilizers.
Dr. Atta Mouludi-Saleh, Dr. Soheil Eagderi, Dr. Hadi Poorbagher, Dr. Hamid Reza Esmaeili,
Volume 11, Issue 1 (6-2024)
Abstract
This study was conducted to investigate the ecological niche overlap of two sympatric species, Paracapoeta trutta and Capoeta damascina in the Iranian part of the Sirvan River, Persian Gulf basin. For this purpose, during the winter of 2021, sampling was done from eight stations (each with three repetitions). After identification, samples were released into the same sampling sites. Then some 10 environmental factors including depth, water velocity, river width, pH, temperature, electrical conductivity (EC), total dissolved solids (TDS), Altitude, slope, and dissolved oxygen were measured and recorded. Investigating the habitat suitability indices of P. trutta were recorded as pH 7.5-8, temperature about 10°C, TDS 150mg/liter, EC 400μS/cm, altitude 1150 m, depth 15cm, river width about 9m, velocity 1 m/s, slope 2% and dissolved oxygen 9mg/l and for C. damascina as pH 6-6.5, temperature about 10°C, TDS 180 to 200mg/l, EC 300μS/cm, altitude 1150m, depth 25cm, river width about 6m, velocity 0.5 m/s, the slope is 2% and the dissolved oxygen 8mg. The results of the ecological niche overlap showed that two species based on studied environmental factors had the highest overlap value for dissolved oxygen (0.646) and the value for temperature (0.293). The average ecological niche overlap was 0.432 for the two species.
Dr Nader Chaparzadeh, Dr Leila Zarandi-Miandoab, - Mina Ali-Pashaei Dehkhargani,
Volume 11, Issue 1 (6-2024)
Abstract
Texture quality is an important factor in evaluating of fruits. The cut surfaces of the apple fruit turn brown because of the oxidation of phenolic compounds, triggered by polyphenol oxidase enzyme. Preventing the oxidation of phenolic substances and changing color of fruit are very important in the food industry. Due to the adverse effects of chemical additives on human health and increasing consumer preference for natural alternative compounds makes an interesting market for natural plant ingredients. This study was conducted to investigate the effect of some chemical and natural compounds including sodium metabisulfite, and citric acid, aromatic waters (sweats) of chicory, licorice and lemongrass on polyphenol oxidase enzyme activity of apple fruits. The activity of polyphenol oxidase was evaluated spectrophotometrically using pyrogallol as substrate. The optimum temperature and pH values were 32 °C and 7, respectively. It was found that the enzyme activity decreased due to use of natural compounds, sodium metabisulfite and citric acid. In conclusion, polyphenol oxidase activity can be reduced to prevent of fruits browning by using suitable natural compounds instead of chemicals.
Dr. Fatemeh Rabizadeh, Dr. Farzane Bahadori,
Volume 11, Issue 2 (8-2024)
Abstract
Iran, having about 79 species of the genus Lamiaceae, is one of the regions of origin of this genus. About 77% of the identified species of the mentioned genus in Iran have been registered as exclusive species. There is an Iranian Nepeta species, which was previously taken as a separate species in botanical reference sources, but has been reclassified as a variety of Nepeta kotschyi in the flora of Iran (Jamzad, 2012). In this research, the correctness of the taxonomic position of these two species by examining their various morphological and micromorphological traits such as plant height, leaf size, canopy, type of hairs and nuts, using stereo electron microscope (SEM) photos and SPSS statistical studies. The results of morphological and microstructural studies of the two species N. persica and N. kotschyi showed that there is a significant difference in the characteristics such as the shape of the leaf, the hairs of its apertures and also the height of the two species. Although these differences in the size and shape of the seeds were not clearly observed, in this study, both N. kotschyi and N. persica species had reticulated nuts with papilus. Also, the appearance of the long hairs on the leaves of the two species is completely different. The hairs in N. persica species have papilus, but the hairs in N. persica species have a smooth surface. Therefore, it was suggested that the two species are independent.
Dr Saeed Mohammadi, Dr Hossein Barahouei,
Volume 11, Issue 3 (12-2024)
Abstract
O Using the Maxent model and presence data for two species, Androctonus crassicauda and A. sistanus, from the scorpions of Sistan and Baluchestan province, which were collected through sampling and reviewing previous studies in the region, predictions have been made regarding their potential distribution. The results of this research, which predicts some ecological characteristics of scorpions, showed that the distribution of both species is greater in the northern regions of the province, and this distribution is expected to increase in the future. The average temperature in the wettest season of the year (Bio8), the amount of precipitation in the coldest month of the year (Bio19), and vegetation have played a role in modeling the current distribution of the species A. crassicauda, while the average temperature in the wettest season of the year (Bio8), vegetation, and the annual temperature range (Bio7) have been significant for the future (2070). Precipitation in the driest month of the year (Bio18) and vegetation cover have the gr
Zahra Tavakoli, Behnaz Saffar, Karim Mahnam, Rohollah Hemmati,
Volume 11, Issue 3 (12-2024)
Abstract
One of the crises in the future for humanity is the epidemic of infectious diseases due to the antibiotic resistance of bacteria. Histatins family has antimicrobial activity against drug-resistant strains and wound healing properties. In this study, the first molecular dynamics simulation on Histatin 3 in the existence of water molecules and ions and also in the existence of Sodium Dodecyl Sulfate (SDS) micelle as a model of membrane bacteria was done separately via the GROMACS 5 package for 50 ns. Then, to increase antibacterial properties, eight mutations were designed and their structures were prepared. Then MD simulation was performed for each mutation with the same previous conditions and binding free energy via the MM/PBSA method of peptides with SDS micelle was calculated. Finally, 950 ns MD simulation in these conditions showed that the D1A-G9W mutation had the best binding free energy to the SDS micelle. Then this peptide and wild Histatin 3 peptide were synthesized, and antimicrobial properties were evaluated experimentally. The results of microbiological tests (MIC) indicated the value of this peptide, which is effective on gram-positive bacteria.