Gemifloxacin Mesylate

In pre-antibiotic times, various highly contagious diseases like cholera, smallpox and tuberculosis were widespread worldwide. Penicillin discovery in the late 1920s was a groundbreaking moment in medical history, saving countless lives. However, over the next few decades, microbes developed antibiotic resistance, leading to a global public health threat known as antimicrobial resistance (AMR). Pseudomonas aeruginosa is a major contributor to hospital-acquired infections, affecting millions of patients and causing numerous deaths annually. Several non-[Formula: see text]-lactam antibiotics combat these infections effectively, while their effect on P. aeruginosa quorum sensing (QS) has been insufficiently explored. We have undertaken comprehensive research to understand the effect of non-[Formula: see text]-lactam antibiotics on various targets of P. aeruginosa. Using molecular simulations, we scrutinize these antibiotics” dynamic behavior and stability. Based on toxicity, binding energy and binding site, platensimycin and sulfasalazine were identified as promising candidates against various targets of P. aeruginosa. The binding energies for sulfasalazine and platensimycin with LasA were found to be −8.1 and −8.6 kcal/mol, respectively. Both of these leading antibiotics were interacting at the active sites of all tested proteins (LasA, LasI and PqsR). The examination of molecular dynamics confirmed the stable complex formation of the lead non-[Formula: see text]-lactam antibiotics with all selected target proteins under normal physiological conditions. These findings emphasize the potential efficacy of platensimycin and sulfasalazine. They could potentially be repurposed for targeting the QS of P. aeruginosa.

Streptococcus agalactiae infections in tilapia are indeed a major concern in the global aquaculture industry, leading to significant economic losses. This study describes the isolation, virulence factors, pathogenicity and antibiotic susceptibility pattern of S. agalactiae in cultured Nile tilapia (Oreochromis niloticus) from aquaculture farms in Kerala, India. The diseased fish showed erratic swimming, lethargy, eye opacity, exophthalmia, darkened body, ascites and haemorrhages. Histopathological findings revealed hepatocytic vacuolization and meningitis. Molecular serotyping of the S. agalactiae isolates identified the serotype Ia. In terms of virulence characteristics, the S. agalactiae isolate obtained from tilapia sample had fbsA, cfB and pbp1A/ponA genes, and they were moderate biofilm producers. It is a matter of concern that the isolates were resistant to the tested macrolides, glycopeptides, chloramphenicol, tetracycline, sulphonamides, lincosamides, oxazolidinones and beta lactam group of antibiotics. Pathogenicity of the isolated strain was tested by experimental challenge through intraperitoneal injection of the isolated strain in Nile tilapia.100 %, 80 %, 40 % and 20 % mortality at doses of 1.0 × 10⁸, 1.0 × 10⁶, 1.0 × 10⁴ and 1.0 × 10² CFU/ml, respectively were recorded in the challenged fish. Level of liver enzymes such as Aspartate aminotransferase (AST) and Alanine Aminotransferase (ALT), and glucose were significantly increased compared to that in control. The haematological indices such as RBC and haemoglobin counts were significantly reduced, while WBC count increased in the challenged fish. The haemolysis test on blood agar plate showed beta haemolysis (β). The emergence of multidrug-resistant pathogen S. agalactiae in tilapia farms in the state is an early warning for appropriate preventive measures to be taken to control their spread across farms as tilapia culture is widely popular in the state.