مشخصات پژوهش

Unlike normal cells, cancer cells receive asparagine amino acids from extracellular sources. In order to evacuate this amino acid from the surrounding of cancerous cells, some cancer patients receive the commercially available asparaginase enzyme producing by Escherichia coli as a medicine. Due to the immunogenicity of this enzyme, allergic reactions and immune responses can be observed in the patient's body. Endophytic bacteria have been identified as new drug producing sources recently. In the present study, the possibility of production of L-asparaginase with more appropriate immunological parameters by this kind of bacteria was investigated through bioinformatics methods. To investigate the presence of this enzyme in endophytic bacteria BLAST-P with E.coli asparaginase enzyme sequence against 275 endophytic bacteria were performed. The results with identity more than 35%, coverage more than 50%, and E-value less than 4-10 were selected. To prediction of allergenicity, antigenicity and the number B and T lymphocytes epitopes, E.coli asparaginase enzyme sequence and selected sequences were analyzed with Algpred, Antigenic Peptide Prediction, VaxiJen, ABCpred, ProPredI and ProPred softwares. According to the results, a total of 9 sequences of known and hypothetical proteins were identified in 6 bacteria. The comparison of the mentioned immunological characteristics of these sequences showed that some of the asparaginase enzymes produced by endophytic bacteria possess more suitable immunological indices. Therefore, the therapeutic use of these enzymes is possible.