Muhammad Kaleem Sarwar, Tahir Iqbal, Iqra Azam, Aqsad Rashda, Anum Zahra, Saira Bashir, Amina Khatoon
Halophilic bacteria thrive in environments with high salt concentrations, making the Khewra salt mine in Punjab, Pakistan, an ideal site for their study. This research focuses on two Gram-negative bacterial strains, K7 and K8, isolated from saline water bodies within the mine. The growth of these strains was analyzed across a range of NaCl concentrations from 1M to 4.5M, with optimal growth observed at 2M and 1.5M NaCl for K7 and K8, respectively, indicating their moderately halophilic nature. Additional growth conditions revealed optimal results at pH 8 and temperatures between 30°C and 37°C. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain K7 is closely related to the Halomonas genus, while strain K8 aligns with the Chromohalobacter species. Antibiotic resistance testing demonstrated that both strains are resistant to Ciprofloxacin, Tetracycline, and Streptomycin, yet susceptible to Chloramphenicol, Erythromycin, and Gentamycin.