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Hajar Mohammadi Barzelighi,1 Bita Bakhshi,2 Bahram Daraei,3 Hossein Fazeli,1 Bahram Nasr Esfahani1 1Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran; 2Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran; 3Department of Toxicology and Pharmacology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, IranCorrespondence: Bita BakhshiDepartment of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Jalal-Ale-Ahmad Ave, Tehran 14117-13116, IranEmail b.bakhshi@modares.ac.irAim: The purpose of this study was to analyze the sequence of azurin gene in relation to its expression in Pseudomanas aeruginosa strains isolated from different clinical specimens of burn patients. Moreover, in silico sequence analysis of azurin gene using globally reported sequences was intended.Materials and Methods: Fifty-nine multidrug-resistant P. aeruginosa isolates were selected from different clinical specimens of patients suffering from burn wound infections in two university hospitals and subjected to antibacterial susceptibility testing. The frequency and genetic diversity of the azurin gene was determined by polymerase chain reaction (PCR) and Sanger sequencing. The azurin gene sequences were compared with the sequence data from other countries. The expression level of azurin gene in P. aeruginosa isolates with different azurin sequences from different clinical specimens was evaluated by real-time PCR.Results and Conclusion: About 98%– 100% of the isolates were resistant to gentamicin, tobramycin, cefoxitin, ciprofloxacin, amikacin, and imipenem, while 100% and 23.9% of the isolates were susceptible to colistin and ceftazidime, respectively. Only eight point mutations were detected with amino acid substitutions in only two positions (81 and 102). In global analysis, 93% of strains showed missense mutation at positions 81 (alanine to threonine). The majority (81%) of Iranian strains were allocated to two major clusters distinct from the rest of world, which may suggest that strains from Iran have made a distinct genetic stockpile through point mutations which has established them separate from the other counties. However, 19% were distributed in different clusters together with the strains from different countries of North and South America, Europe, South and East Asia. The expression level of the azurin gene was statistically higher in the isolates collected from the blood of burns patients with systemic infection compared to the isolates collected from other specimens (wound, catheter and tissue), which shows a positive correlation between azurin gene expression and increased pathogenicity and capability for dissemination. This study may open new insight about azurin genetic variation and significance in P. aeruginosa pathogenesis.Keywords: azurin, pathogenicity, Pseudomonas aeruginosa, burn, sequence analysis

Background & objectives: Association between polymorphisms in the natural resistance associated macrophage protein 1 (NRAMP1) gene and susceptibility to cutaneous leishmaniasis (CL) has been demonstrated worldwide; however, the reported results were inconsistent. This study aimed to determine the association of NRAMP1 variants with susceptibility to CL infection and patients′ response to treatment in Isfahan province of Iran. Methods: Peripheral blood samples were collected from 150 patients with CL and 136 healthy controls. The CL patients were treated with intralesional injection of meglumine antimoniate. The polymorphic variants at NRAMP1 (A318V and D543N) were analyzed using PCR-RFLP. The chi-square test and Fisher′s exact test were used to compare frequencies of alleles and genotypes of polymorphisms between patient and healthy control populations. Results: There was a statistically significant difference in the D543N (rs17235409) polymorphism between the CL patients and healthy controls (p=0.008). However, no significant association was detected for A318V (rs201565523) polymorphism between groups (p=0.26). In addition, there was a lack of association between D543N and A318V genotypes with response to treatment (p=0.54 and p=0.31, respectively). Interpretation & conclusion: The results indicated that genetic variations of D543N (rs17235409) might be associated with susceptibility to CL infection. These data may be used for detection of sensitive individuals and prevention of CL in endemic areas.