Study bacteria infection and treatment expression of L-aspaeaginase from patients of Iraq

This study investigates bacterial infection and treatment by expressing L-asparaginase from patients in Iraq. The ansB gene encoding L-asparaginase from Psychrobacter cryohalolentis was mutated to reduce immunogenicity in H. pylori and E. coli. Successful insertion of mutations was confirmed by DNA sequencing. However, only the native protein retained enzymatic and cytotoxic activity, exhibiting optimal activity at pH 8.5 and 60°C. It effectively inhibited cell growth in tumor cell lines by 80-95%. Circular Dichroism analysis revealed that both native and variant proteins maintained an α-helix structure, suggesting structural stability. Molecular Dynamics simulations demonstrated that the G113D mutation disrupted substrate-catalytic site interactions, leading to loss of catalytic activity in variants. Future work involves removing the G113D mutation to restore enzymatic activity and assessing the immunogenic potential of the variants, particularly the quadruple mutant, which may offer reduced immunogenicity while retaining therapeutic efficacy. This study sheds light on potential strategies for enhancing L-asparaginase treatment efficacy and reducing immunogenicity in bacterial infections.