Microbiology
Zeynab Mohseni Moghadam; Raheleh Halabian; Hamid Sedighian; Elham Behzadi; Jafar Amani; Abbas ali Imani fooladi
Abstract
Background & Objective: A main contest in chemotherapy is to obtain regulator above the biodistribution of cytotoxic drugs. The utmost promising strategy comprises of drugs coupled with a tumor-targeting bearer that results in wide cytotoxic activity and particular delivery. The B-subunit of Shiga ...
Read More
Background & Objective: A main contest in chemotherapy is to obtain regulator above the biodistribution of cytotoxic drugs. The utmost promising strategy comprises of drugs coupled with a tumor-targeting bearer that results in wide cytotoxic activity and particular delivery. The B-subunit of Shiga toxin (STxB) is nontoxic and possesses low immunogenicity that exactly binds to the globotriaosylceramide (Gb3/CD77). Gb3/CD77 extremely expresses on a number of human tumors such as pancreatic, colon, and breast cancer and acts as a functional receptor for Shiga toxin (STx). Then, this toxin can be applied to target Gb3-positive human tumors. In this study, we evaluated DT390-STXB chimeric protein as a new anti-tumor candidate via genetically fusing the DT390 fragment of DT538 (Native diphtheria toxin) to STxB. Methods: This study intended to investigate the DT390- STxB fusion protein structure in silico. Considering the Escherichia coli codon usage, the genomic construct was designed. The properties and the structure of the protein were determined by an in silico technique. The mRNA structure and the physicochemical characteristics, construction, and the stability of the designed chimeric protein were analyzed using computational and bioinformatics tools and servers. Hence, the GOR4 and I-TASSER online web servers were used to predict the secondary and tertiary structures of the designed protein. Result: The results demonstrated that codon adaptation index (CAI) of dt390-stxB chimeric gene raised from 0.6 in the wild type to 0.9 in the chimeric optimized gene. The mfold data revealed that the dt390-stxB mRNA was completely stable to be translated effectively in the novel host. The normal activity of the fusion protein determined by considering the secondary and tertiary structure of each construct. Energy calculation data indicated that the thermodynamic ensemble for mRNA structure was -427.40 kJ/mol. The stability index (SI) of DT390-STxB was 36.95, which is quite appropriate to preserve the stability of the construct. Ultimately, the DT390-STxB was classified as a steady fusion protein according to the Ramachandran plot. Conclusion: Our results showed that DT390-STXB was a stable chimeric protein and it can be recruited as a candidate of novel anti-tumor agents for the development of breast cancer treatment.
Microbiology
Sharareh Mohammad Hasani; Reza Mirnejad; Vahhab Piranfar; Jafar Amani; Mohamad javad Vafadar
Volume 11, Issue 2 , April 2016, , Pages 144-150
Abstract
Background: Rapid diagnosis and differentiation of Brucella is of high importance due to the side effects of antibiotics for the treatment of brucellosis. This study aimed to identify and compare PCR-ELISA as a more accurate diagnositc test with other common molecular and serological tests. Methods: ...
Read More
Background: Rapid diagnosis and differentiation of Brucella is of high importance due to the side effects of antibiotics for the treatment of brucellosis. This study aimed to identify and compare PCR-ELISA as a more accurate diagnositc test with other common molecular and serological tests. Methods: In this experimental and sectional study, during March 2014 to Sep 2015, 52 blood samples of suspected patients with clinical symptoms of brucellosis were evaluated in medical centers all over Iran with serum titers higher than 1:80. Using two pairs of specific primers of Brucella abortus, B. melitensis and DIG-dUTP, Fragment IS711 (The common gene fragment in B. melitensis and B. abortus) was amplified. DIG-ELISA was performed using specific probes of these 2 species of Brucella and patterns were subsequently analyzed, then positive responses were compared by detecting gel electrophoresis. Results: PCR-ELISA method detected all 28 samples from 52 positive samples. Its sensitivity was 6.0 pg concentration of genomic DNA of Brucella. In gel electrophoresis method, 22 samples of all positive samples were detected. PCR-ELISA was more efficient than PCR and bacterial culture method at P-value Conclusion: PCR-ELISA molecular method is more sensitive than other molecular methods, lack of mutagenic color and also a semi-quantitative ability. This method is more effective and more accurate compared to PCR, serology and culture of bacteria. PCR-ELISA does not have false responses. The limitation of this method is detection of bacteria in the genus compared to Multiplex PCR and Gel Electrophoresis.
