Showing 51 results for Peptide
Soheila Talesh Sasani, Bahram Mohammad Soltani, Mehrdad Behmanesh, Naser Safaie,
Volume 4, Issue 2 (9-2013)
Abstract
Sheath blight, caused by Rhizoctonia solani AG1-IA, is one of the most destructive disease. Conventional methods of disease control using fungicides may develop new problems. Therefore, understanding molecular mechanisms of plant–pathogen interaction is necessary to adopt effective approaches for managing the disease. Here for the first time, by using bioinformatics tools and RT-PCR analysis and sequencing confirmed the presence of a Magnaporthe oryzae Avr-pita gene orthologous sequence designated as Rhiz-pita1 gene in three different geographic isolates of R. solani AG1- IA( A2,R1 and T2) genome. SignalP program predicted a secretion signal upstream of Rhiz-pita1 gene. Nucleotide sequences of 5' region of Rhiz-pita1 gene from geographical isolates showed 99% identity in exons and 100% in introns which are characteristics of fast evolving effector proteins. Also, 98% homology between Rhiz-pita and M.oryza-pita1gene suggests that Rhiz-pita encodes an effector protein. Howevere, more researchs are necessary to confirm of this suggestion. Keywords: Rhizoctonia solani, signal peptide Rice blast , Effector
Zahra Hajihassan, Seyed Kazem Hosseini, Alireza Zomorodipour,
Volume 7, Issue 2 (9-2016)
Abstract
Human activin A is a homodimer of βA subunit which is synthesized in the form of prepro-activin with 426 amino acids; mature activin A with 116 amino acids is processed from this larger precursor protein. This protein which was extracted for the first time from follicular fluid is a strong stimulator of FSH biosynthesis. The functions have been found to be exerted by activin, including roles in cell proliferation, differentiation, apoptosis and survival of neurons. As this protein plays a considerable role in the treatment of neurodegenerative disease such as Alzheimer,s disease and wound repair, in this study for the first time was expressed in three different strains of E.coli. Activin A has disulfide bonds in its native and functional structure, so the cytoplasmic reducing environment of E.coli is not appropriate for its expression. Therefore, the oxidative space of periplasm for production of correctly folded activin A was considered. In this study, h-activin A cDNA and modified Iranian Bacillus Licheniformis α-amylase signal peptide obtained from NCBI data bank after codon optimization was cloned in pET21b(+) vector and transformed to BL21(DE3)pLysS, BL21(DE3)Rosetta gami and BL21(DE3) strains of E.coli. Expression occurred via induction of promoter with IPTG. Consequently, extracted proteins from these three strains were compared with each other using SDS-PAGE, Dot blot and western blot techniques. The data shows activin A expression especially in BL21(DE3) and BL21(DE3)Rosetta gami strains of E.coli.
Reyhane Chamani, S. Mohsen Asghari,
Volume 7, Issue 2 (9-2016)
Abstract
Endostatin suppresses growth and progression of many tumors through binding to endothelial cell surface and extracellular matrix proteins like integrin, heparin, matrix metalloproteinase-2 and transglutaminase-2. There is an arginine rich motif on the surface of endostatin that is essential for binding to some of aforementioned proteins. It has been shown that a 27 amino acid peptide derived from amino terminal of endostatin responsible for its anti-angiogenic and anti-tumor activities and mutation of histidines bound to Zn significantly reduce its activity. In the present study, as regards the importance of Zn-binding loop in amino terminal and arginine 27 in carboxyl terminal, peptides corresponding to this region and a mutated variant including isoleusin 26 to arginine mutation synthesized and their structure and interaction with matrix metalloproteinase-2 and transglutaminase-2 analyzed using fluorescence spectroscopy, molecular dynamic and docking simulation techniques. This study aimed to analyze effect of placing two positively charged arginines on the structure and interaction of this fragment of endostatin. Results showed that placing two arginines close together in the carboxyl terminal of peptide increases fluctuations in total structure of peptide, alters Zn-binding loop in the amino terminal and makes binding energy of peptide to matrix metalloproteinase-2 and transglutaminase-2 more negative. It can be inferred that repulsion of two positively charged arginines in carboxyl terminal induces conformational changes in the whole structure and in the amino terminal loop region.
Volume 7, Issue 3 (7-2019)
Abstract
Aims: Breast cancer is the most common cancer in women in several countries. Bioactive peptides have demonstrated their cytotoxic potential in numerous cancer cell lines. In the search for novel bioactive peptides for pharmacological properties, crab is noncommercial protein-rich species. Using enzymatic hydrolysis is an efficient way to recover potent bioactive peptides from marine sources.
Materials and Methods: The aim of this study was to isolate fractions from rocky shore crab hydrolysate with desired molecular weight by ultrafiltration and investigate their cytotoxic activities. Four fractions (>30kDa, 10-30kDa, 3-10kDa and <3kDa) were evaluated for cytotoxic activity against a 4T1 cell line by MTT assay.
Findings: The MTT assay showed that although all fractions from the crab hydrolysate showed some activity, the low molecular weight samples (3-10kDa and <3kDa) were more effective than high molecular weight fractions (>30kDa and 10-30kDa) while the 3-10kDa fraction proved to be the most effective. The low molecular weight fractions significantly reduced the viability of the 4T1 cell lines in a dose-dependent manner upon 24 and 48h. The results were recorded in IC50 values of about 0.40±0.063mg mL-1 for <3 and 0.25±0.026mg mL-1 for 3-10kDa fractions.
Conclusion: Peptide fractions were isolated from the protein hydrolysate of the rocky shore crab Grapsus albolineatus are able to inhibit cancer cells and can be considered as a novel agent in nutraceutical and pharmaceutical ingredient applications.
Volume 8, Issue 1 (1-2019)
Abstract
Efficacy of quercetin on α-amylase, lipase and protease activities via crustacean cardioactive peptide (CCAP) content of the midgut of the diamondback moth, Plutella xylostella (L.) was investigated. Fresh cabbage leaf discs were dipped in quercetin solution at different concentrations (100, 500 and 1000ppm) for 10 seconds. Third instar larvae of P. xylostella were fed on leaf dipped in quercetin solutions for 5 days. α-Amylase, lipase and protease activities were evaluated for 5 days. Quercetin significantly decreased lipase, protease and α-amylase activities in the midgut. The results of competitive ELISA showed that different concentration of quercetin had no effect on short neuropeptide F, tachykinin-4 and allatostatin content of the midgut, but it was shown that quercetin (500 and 1000ppm) decreased CCAP content of the midgut. Moreover, incubation of dissected midgut with CCAP increased α-amylase, lipase and protease activities. The injection of CCAP into the hemocoel clearly increased α-amylase, lipase and protease activities. Here, for the first time, it was confirmed that feeding on leaf dipped in quercetin, decreases CCAP content in the midgut of P. xylostella, that itself led to decrease of α-amylase, protease and lipase activities.
Volume 8, Issue 3 (9-2019)
Abstract
Aims: the aim of this study was to extract gelatin from the skin of farmed great sturgeon at different temperatures, hydrolysis using Alcalase enzyme, and to measure molecular weight distribution of peptides, amino acid composition and antioxidant activity of hydrolysates.
Materials & Methods: After removing pigments and non-collagenous proteins, defatting, and swelling of triple-helix structure, gelatin was extracted at temperatures of 50, 60, 70 and 80 ºC for 6 h and then hydrolysed using Alcalase (E/S ratio of 1:20 w/w) for 3 h. Molecular weight distribution of peptides, amino acid composition and antioxidant activity of hydrolysates were determined.
Findings: Degree of hydrolysis reached its maximum within the first 30 min. Hydolysate from extraction temperature of 80 ºC had the highest DH. No significant differences were found among hydrolysates with regards to amino acid composition and peptide molecular weight distribution. At of 60 ºC, the content of small peptides (< 1 kDa) and amino acids were slightly higher compared to other samples. This could influence antioxidant activity to some degree. At higher extraction temperature of gelatin, the efficacy of hydrolysates in preventing the loss in total sulfhydryl groups content was decreased (P < 0.05) while TBARS and surface hydrophobicity were not influenced (P < 0.05).
Conclusion: Extraction temperature of gelatin did not reveal a considerable effect on properties and antioxidant activities of the resulting hydrolysates and gelatin hydrolysates with antioxidant activity and rich in peptides with molecular weight less than 1 kDa could be produced at 50 ºC.
Volume 8, Issue 3 (9-2022)
Abstract
Backgrounds: A short sequence of viral protein or peptide, can be used as a potential vaccine for the treatment of that virus. Considering all variants of concern (VOC), vaccine design with peptide for Severe Acute Respiratory Syndrome coronavirus 2 (SARS CoV2) is a challenging job for scientists.
Materials & Methods: In this current study, an epitope containing peptide vaccine for nonstructural protein 4 (nsp 4) of SARS CoV2 coronavirus has been predicted. With the help of a modified method for both B and T call epitope prediction, verified by molecular docking studies, linear B cell and T cell epitopes for nsp4 protein, are predicted here. Predicted epitopes are analyzed further with population coverage calculation and epitope conservancy analysis.
Findings: A short peptide sequence 74QRGGSYTNDKA84 has been selected as B cell epitope considering the scores for surface accessibility, hydrophilicity, beta turn prediction for each amino acid residues.
Similarly, the peptide sequences 359 FLAHIQWMV367 and 359 FLAHIQWVMFTPLV373 are predicted as T cell epitopes for MHC-I and MHC-II molecules. These two potential epitopes can interest with HLA-A*02:01 and HLA-DRB*01:01, MHC allelic proteins respectively with lowest IC50 values.
Furthermore, no amino acid mutations are observed in GISAD Global initiate on sharing all influenza data) database for alpha, beta, gamma and delta variance of concerns (VOC). Among seven amino acid point mutation of nsp 4 protein in Omicron variant, none of them is present in the peptide sequences of predicted epitope-based vaccines.
Conclusion: The short peptide sequences can be predicted as vaccines to prevent coronavirus infections for all variants of concerns.
F. Doustdar , R. Aghdami , F. Mehrnejad , N. Chaparzadeh ,
Volume 9, Issue 1 (1-2018)
Abstract
Aims: Today, due to the advent of drug resistance in cancer cells against conventional drugs, attention has been paid to the development of anti-cancer drugs with new mechanisms. Pardaxin is an amphipathic polypeptide neurotoxin.The aim of this study was to investigate the interaction of antimicrobial peptide pardaxin with DPPC (composed of 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine) bilayers by molecular dynamics simulation.
Materials & Methods: In the present study, simulations for different membrane environments were designed under neutral pH conditions. At first, the Linux system was used to install the VMD 1.8.6 (Visual Molecular Dynamics) software; then, Gromacs 4.5.5 software was used to perform all the simulations. The pdb peptide structure (1XC0) was prepared from the Protein Data Bank and DPPC lipid bilayer was used for lipid-peptide simulation.
Findings: During the 500 nanoseconds of simulation, the peptide was infiltrated into the membrane. In the DPPC system, at first, the number of hydrogen bonds between the peptide and the lipid bilayer were increased and, then, remained almost constant until the end of the simulation and decreased over time with the number of hydrogen bonds between peptides and water. Pardaxin contacted with the membrane surface and entered into the membrane. In the presence of the peptide, the thickness of the membrane and the range of each lipid decreased and the membrane penetration increased.
Conclusion: The mechanism of Pardaxin is dependent on the bilayer composition, so that the pardaxin peptide contacts with DPPC lipid membrane surface and enters into it.
R. Ghasemi , H. Hashemzadeh , H. Razavi , B. Yakhchali ,
Volume 9, Issue 1 (1-2018)
Abstract
Introduction: Growth hormone is a non-glycosylated polypeptide strand of the pituitary glands of all vertebrates that has a wide range of biological activities and considering the importance of this hormone and its importance and diverse therapeutic applications in medicine, its recombinant production can be of great importance. In recent decades, protein engineering and genetic engineering have resulted in a high level of expression and production of this protein in a variety of hosts, including Escherichia coli bacteria using new techniques and methodes, hormone purification and assay are carried out easily. Therefore, the aim of this review was to investigate the production of recombinant human growth hormone (rhGH) and future challenges.
Conclusion: One of the problems of the expression and purification of the human growth hormone may involve that maybe noted the production of inclusion bodies in the expression of recombinant proteins in the cell cytoplasm, the contamination caused by host proteins, low protein recovery from these inclusion bodies, low protein secretion into the Periplasmic space, high cost of production, especially in Purification stage and so on. Due to the lack of need for glycosylated hormone and high efficiency and simplicity of work, bacterial systems, especially Escherichia coli, are the most economical and effective systems for the expression of heterologous proteins. The hormone purification stage is usually the most costly process. Therefore, an optimal design for achieving the highest target protein recovery with the elimination of all contamination from the final product and reducing the purification step is required.
Volume 9, Issue 4 (12-2023)
Abstract
Aims: Antimicrobial peptides (AMPs) are beneficial compounds that could be used as a new and effective method to suppress microbes. Both Ib-AMP4 and LL37 are antimicrobial peptides with a wide range of antimicrobial activities. This research aimed to evaluate the antibacterial potential of LL37-rIb-AMP4 hybrid protein as an antimicrobial agent against pathogenic bacteria. Therefore, its antibacterial effects against Acinetobacter baumannii, Pseudomonas aeruginosa, vancomycin-resistant Enterococcus (VRE), and methicillin-resistant Staphylococcus aureus (MRSA) were investigated in vivo and in vitro.
Materials & Methods: In this study, antimicrobial peptides rIb-AMP4, LL37, and LL37-rIb-AMP4 were expressed, purified, and refolded, and their synergistic and antibacterial effects in combination with each other (LL37+rIb-AMP4) and as fusion proteins (LL37-rIb-AMP4) were tested against A. baumannii, P. aeruginosa, VRE, and MRSA cells in vitro (MIC, time kill, and SEM) and against P. aeruginosa and VRE cells in vivo.
Findings: LL37-rIb-AMP4 Protein with molecular weight= 28 KD was correctly produced and purified. Despite the lack of synergistic effects between LL37 and rIb-AMP4 peptides in vitro, the stability test results showed higher stability for LL37-rIb-AMP4 hybrid protein.
The findings of in vivo tests confirmed that all infected mice were improved with LL37-rIb-AMP4 and no signs of bacteria were observed in their blood and spleen samples. Also, these results confirmed the stability and higher activity of LL37-rIb-AMP4 than the single form of these proteins.
Conclusion: Considering the antimicrobial potential of the produced proteins, it seems that the recombinant LL37-rIb-AMP4 protein could be considered and used as a stable and active antimicrobial drug in future studies.
S. Moasses Ghafary, M. Nikkhah, Sh. Hatamie, S. Hosseinkhani,
Volume 10, Issue 1 (3-2019)
Abstract
One of the main challenges in the treatment of genetic disorders, such as cancer, is of drug delivery systems and their inability to monitor and track delivered drug to the targeted site. Therefore, the design of novel with dual capabilities of nuclear drug delivery and tracking into a research priority for this field’s The aim of this study is to design based on both non-cytotoxic quantum dots and chimeric peptides, with dual tracking and delivering small genetic agents into the nucleus. The GQDs with green emission color were synthesized by Hummer’s and methods and characterized by UV-Vis, photoluminescence (PL), Raman spectroscopies, and scanning electron microscopy (SEM). conjugated with MPG-2H1 chimeric peptides through noncovalent interactions. Following conjugation step, the ζ-potential of the complex increased (From -38.6 to -11.1 in complex1, -9.6 in complex2 and -5.74 in complex3). The conjugation was confirmed by native acrylamide gel retardation assay. The of the GQDs was investigated by MTT assay and finally, was carried out. The results showed that MPG-2H1/ GQD complexes can enter cells; however, free-GQDs didn’t enter the cells significantly.
M. Monsefi , H. Erfan-Niya , R. Ghadari ,
Volume 10, Issue 1 (3-2019)
Abstract
Aims: Molecular insights into the analyte-bioreceptor interactions play a vital role in the efficacy of designing biosensors. Biosensors that utilize aptamers as bioreceptors are highly efficient with high specificity and reusability. Aptasensors can be used in a variety of conditions of in vivo or in vitro. The aim of this study was to study the changes in the solvent conditions of the binding of MUC1-G peptide and the anti-MUC1 aptamer.
Materials and Methods: The molecular dynamics simulation method has been used to investigate the change of molecular interactions due to selective variations in solvent conditions. The results can be used to reflect a variety of environments, in which the aptasensor utilizes anti-MUC1 S2.2 aptamer as a bioreceptor and MUC1–G peptide as a biomarker.
Findings: Based on the calculated binding energies, the medium containing 0.10M NaCl and anti-MUC1 S2.2 aptamer demonstrates the highest affinity toward the MUC1-G peptide among the studied concentrations of NaCl, and the arginine amino acid has a key role in the aptamer–peptide binding. Conclusion: The results of MD simulation indicated that the increase in the concentration of NaCl in the interaction environment leads to a decrease in binding energies; therefore, the binding affinity of the anti-MUC1 aptamer to MUC1-G peptide decreases. Insights from present modeling demonstrate the selectiveness and sensitivity to solvent conditions, which should be considered in the development of biosensors.
Volume 10, Issue 2 (4-2021)
Abstract
Piscidin has a wide range in killing microorganisms including bacteria, fungi, viruses, parasites and has strong anti-tumor activity and plays a role in increasing innate immunity and also does not provide resistance against bacteria; Therefore, it is of great importance in aquaculture. In this study, piscidin gene of Sparus aurata in vector pTZ57R / T was cloned. In this research, ligation product was transferred to component cell of E. coli DH5α strain. Plasmid extraction was performed from single colonies observed in ampicillin plate. Confirmation of the accuracy of single colonies grown in this research was performed by direct PCR and sequencing. The amplified cDNA fragment of the gilthead seabream piscidin gene consists of 310 nucleotides and 57 amino acids. The results of this research show that piscidin gene has been successfully cloned in pTZ57R / T vector. Comparison of nucleotide sequence of piscidin gene in this study showed high similarity with piscidin 5 of Morone chrysops. The comparison of the amino acid sequence of signal peptide piscidin is quite similar to Dicentracin-like of that species registered in the genebank, and mature peptide piscidin sequence is similar in only three amino acids to Pleorocidin-like of Poesila farmosa and Dicentracin-like of Sphaeramia orbicularis. This study could be a step towards further studies of piscidin peptide.
Volume 10, Issue 2 (4-2021)
Abstract
In this experiment, head wastes were prepared and enzymatically hydrolyzed using alcalase (2.4 L) enzyme. The hydrolysate was fractionated by ultrafiltration with 10 kDa molecular weight cut-offs and the desired fraction was encapsulated following ion coagulation method (chitosan and triphosphate (TPP)) in nanochitosan capsules. Encapsulation process was optimized based on different ratios of chitosan:TPP and different concentrations (1, 5 and 10 mg/ml) of peptidic fraction. Finally, the degree of hydrolysis and the length of the peptides obtained from enzymatic hydrolysis were determined. The nanocapsules were examined for size, zeta potential and polydispersity index (PDI) using dynamic light scattering (Malvern, England). Structural and surface morphology studies including scanning electron microscopy (SEM) and infrared spectroscopy (FTIR) of capsules produced under favorable conditions were also performed. Particle size was measured in various concentrations and treatments in the range of 30 to 150 nm. The best results were obtained in the treatment of 2: 1 ratio of chitosan to polyphosphate and concentration of 10 mg / ml. The size, dispersion index, zeta potential and size of nanocapsules in the optimal conditions were 0.375, 2020 and 30.13 nm, respectively, and storage conditions at -20 °C had no effect on the quality of nanocapsules. Based on the efficiency study, it was found that fraction with a concentration of 10 mg/ml is well encapsulated by chitosan with an efficiency of 91.04 ± 0.18 percent. The results showed that chitosan-TPP could be used for nanocapsulation of bioactive peptides with an approximate molecular weight of less than 10 kDa.
Z. Safari, S. Soudi, A. Zavaran Hosseini, H. Bardania, M. Sadeghizadeh ,
Volume 10, Issue 4 (12-2019)
Abstract
Aims: One of the most important regenerative medical purposes is the production of alternative tissues with proper function. Fibroblast cells are one of the most important types of cells in the repair process that also play a role in the formation of blood vessels. Stimulation of fibroblastic cells requires the appearance of external signals to begin the proliferation and recall of other cells, as well as angiogenesis. The aim of this study was to investigate the effects of M13 in combination with RGD peptide on fibroblastic cells.
Materials and Methods: For this study, M13 bacteriophage was first amplified and isolated. Then RGD peptide was synthesized and purified. Then, isolated mouse fibroblastic cells were culture on surfaces coated with M13 bacteriophage, bacteriophage M13 and RGD, gelatin, and surfaces without coated as a control for 48 hours. MTT assay was used to measure the proliferation and survival of cells, and then the expression of FGF-2, TGF-β1 and VEGF-A genes was measured by real-time PCR.
Findings: The results of this study showed that the M13 and RGD bacteriophage increased cell proliferation and the fibroblast cell survival rate. In addition, expression of FGF-2, TGF-β1 and VEGF-A genes in cultured fibroblasts on the M13 and RGD bacteriophages surface increased significantly.
Conclusion: Our research showed that scaffolds of M13 bacteriophage and RGD peptide are nontoxic and bio-compatible so they can be a suitable candidate for induction of repair and angiogenesis in tissue engineering.
M. Bahri , S. Hasannia, B. Dabirmanesh , H.h. Zadeh,
Volume 10, Issue 4 (12-2019)
Abstract
Introduction: Nowadays, bone tissue repair with increasing bone disorders and injuries have special importance. Bone tissue engineering provided specific solutions to these problems. The present study was conducted with the aim of purification of recombinant fusion peptide containing hydroxyapatite affinity tag using the ceramic chromatography column.
Material & methods: In this study, a fusion peptide was designed which at one side comprised the heparin-binding domain sequence, which can be attached to various types of growth factors involved in tissue repair and entrap these factors at the site of the lesion. On the other side, it contained a tag, which included a sequence derived from a laboratory study based on phage expression. The reason for keeping the sequence of this tag is to attach the peptide to the scaffold containing hydroxyapatite and purifying the recombinant peptide by the hydroxyapatite column. Therefore, the gene sequence was optimized and synthesized for expression in the prokaryotic host of E.coli strain BL21. Then the gene sequence was subcloned by double digestion with the SacI and BamHI enzymes into the expression vector of pET-21a(+). The expression of the recombinant peptide was investigated by SDS-PAGE and western blot. In order to optimize the purification conditions, two-step purification was carried out by applying fundamental changes in the main work method of the manufacturer company and was purified with acceptable purity. Finally, the existence of peptide assemblies was investigated by the SLD method.
Finding: The results of PCR cloning, enzymatic digestion using SacI and BamHI enzymes and sequencing indicated the accuracy of the cloning process. On the other hand, expression of the fusion peptide was confirmed by SDS-PAGE and Western blot techniques, and its migration onto the gel resulted in a band cleavage of about 12 kDa. Changes made to the manufacturer's workflow allowed the purification process to be optimized and the results of the DLS method showed the purity of the purified peptide.
Conclusion: The results indicate the desirable expression and remarkable purity of the fusion peptide designed in this study.
Volume 11, Issue 0 (6-2008)
Abstract
Objective: DNA vaccines have been widely used to develop immunity against various pathogens including parasites and viruses. The potential of DNA vaccine to induce an effective immune response is related to the expression levels of the encoded protein in eukaryotic cells. Therefore, optimization of plasmid DNA delivery system is a major concern in protein expression in order to make an efficient DNA vaccination. Non-viral vectors such as polymers and cationic peptides have been recently known as efficient gene delivery systems into eukaryotic cells. In this study, transfection efficiency of HPV16E7 gene was evaluated by two non-viral delivery systems in vitro.
Materials and Methods: DNA construct encoding HPV16E7 (pEGFP-E7) was prepared in large scale with high purity. Then, two delivery systems including polymer PEI 25 kDa and polymer-peptide hybrid as PEI600-Tat conjugate were used to compare their efficiency for HPV16E7 DNA transfection in vitro.
Results: Our data demonstrated that both delivery systems including PEI 25 kDa and PEI600-Tat are efficient tools for E7 gene transfection. Although the level of transfected COS-7 cells is higher using PEI 25 kDa in comparison with PEI600-Tat.
Conclusion: Our study indicated that PEI potency for E7 gene transfection was higher than PEI600-Tat in vitro, but its toxicity was obstacle in vivo. Therefore, with regard to low toxicity of PEI600-Tat delivery system and its potent plasmid DNA delivery, it is critical issue to study its potency as new delivery system in vivo.
Volume 11, Issue 2 (5-2022)
Abstract
In this study, the orangefin ponyfish (Leiognathus bindus) was hydrolyzed by alcalase in an enzyme to substrate ratio of 1: 100 for 300 minutes, and the degree of hydrolysis was measured for 5 hours. Also, the hydrolysate was fractionated by centrifugal having molecular mass cutoffs of 3, 10, and 30 kDa, and four peptide fractions were obtained. Then, the antioxidant activity (DPPH and ABTS free radicals scavenging activity) of peptide fractions, as well as hydrolysate, were measured at different hydrolysis times. The degree of hydrolysis was the highest (55.43 ± 2.11%) at a hydrolysis time of 240 minutes. The hydrolysate had a high amount of hydrophobic amino acids (50.6%) which cause antioxidant properties. The results of DPPH radical scavenging activity showed that the highest scavenging activity was obtained at a hydrolysis time of 240 minutes (75.59 ± 1.46). Also, among all the fractions, the 3-10 kDa fraction exhibited the highest scavenging activity compared to other fractions (80.58 ± 2.96% at a concentration of 5mg /ml). Based on the result of ABTS radical scavenging, the highest activity was reported at 240 minutes after hydrolysis (50.54 ± 0.63). Also, among all peptide fractions, the 3-10 kDa fraction had significantly higher scavenging activity than other fractions (84.58 ± 0.44 at a concentration of 5 mg /ml). The results of this study showed that the peptides obtained by enzymatic hydrolysis of orangefin ponyfish are a good candidate for providing antioxidant properties.
Volume 11, Issue 2 (4-2025)
Abstract
Background: The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses a significant global health threat. The host immune response determines the disease severity, with factors like human leukocyte antigen (HLA) genes, age, sex, and nutritional status influencing outcomes. HLA genes, known for their genetic diversity, are implicated in determining susceptibility and severity of infectious diseases. This study investigated the association between HLA class I genotypes and COVID-19 severity in the Isfahan population, Iran.
Materials & Methods: Blood samples were collected from 34 COVID-19 patients with varying levels of disease severity (severe, moderate, and mild). HLA genotyping was performed using polymerase chain reaction-sequence specific primers (PCR-SSP), and in silico analysis assessed the affinity of viral peptides to HLA alleles.
Findings: Statistical analyses revealed that HLA-C07 was more prevalent in patients with severe COVID-19, suggesting a potential association between this allele and the disease severity. Furthermore, HLA-A01 was more prevalent among severe cases, while HLA-A02 and HLA-A03 were less frequent, indicating a possible predisposing role for HLA-A01 and protective roles for HLA-A02 and HLA-A*03.
Conclusion: These findings highlight the role of HLA molecules in COVID-19 severity and offer insights into genetic factors influencing outcomes. Understanding the association of specific HLA alleles, such as HLA-C07, HLA-A01, HLA-A02, and HLA-A03, with the disease progression lays a foundation for advancing personalized preventive and therapeutic approaches. These results contribute to knowledge on host genetics in infectious diseases, paving the way for further research and therapeutic strategies.
Volume 12, Issue 1 (12-2022)
Abstract
In the present study, the goldfish kisspeptin peptide was synthesized using the solid phase synthesis method according to the nucleotide sequence of the goldfish (Carassius auratus) kiss1 gene. Next, an acetyl group was added to the amino group of Tyr1 to increase the biological activity. The synthesized peptide (referred to as ACKiss1) was purified by RP-HPLC and its structure was confirmed using electrospray ionization (ESI) mass spectrometry. To determine the biological activity, ACKiss1, native Kiss1 and commercial GnRH hormone were injected to goldfish, some important parameters of the reproductive physiology were studied. Kiss1 and ACKiss1 were injected with a dosage of 100 μg/kg fish body weight and GnRH was injected with dosages of 100 and 200 μg/kg body weight. 6 hours after injection, blood was taken from the caudal vein and sex hormones were measured in plasma. 24 hours after injection, reproductive indices were measured in a series of fish. In another series of fish, 24 hours after injection, ovarian and brain tissues were separated for histological studies and expression of the reproductive-related genes (cyp19b, gpr54a, and kiss1). The results revealed that significant changes in biochemical parameters and gene expression were recorded in both brain tissue samples and ovarian tissue in ACKISS1 treatment. It was also found in ovarian histology that under the influence of kisspeptin and GnRH, the number of mature oocytes increased significantly.
