Anti-E. coli Gyrase B Monoclonal antibody, Clone 8E4

A SYTO9 real-time polymerase chain reaction assay for detection of pathogenic Leptospira spp. based on amplification of DNA gyrase subunit B (gyrB) gene has been optimized and evaluated for sensitivity and specificity on kidney and urine samples of New Zealand farmed deer. The detection limit was 10(3) cells/ml (2-10 copies/reaction). Comparison of the assay on deer kidneys (n = 268) with culture as the gold standard revealed a sensitivity and specificity of 85% and 99.2%, respectively. For deer urine (n = 113), the assay was compared with known inoculated samples and revealed a sensitivity and specificity of 96.7% and 100%, respectively. The assay was applied for quantifying pathogenic leptospires shed naturally in deer urine and revealed a detectable concentration of 3.7 x 10(3) to 1.7 x 106 cells/ml. To assess the assay's capability for identifying pathogenic Leptospira spp., 14 field isolates of L. borgpetersenii serovar Hardjo-bovis and L. interrogans serovar Pomona were amplified for polymerase chain reaction (PCR) product, purified, and sequenced. When compared with the National Center for Biotechnology Information database, sequence data matched with L. borgpetersenii serovar Hardjo-bovis in 13 samples and L. interrogans serovar Pomona in 1 sample, which was consistent with the microscopic agglutination test (MAT). Sequence analysis of purified PCR product amplified directly from kidney and urine samples also yielded serovar-comparable MAT results. Results suggest that the assay is rapid, sensitive, and specific for detection of pathogenic leptospires in deer clinical samples. The developed assay can also be used for estimating the concentration of leptospires and identifying Leptospira spp. in combination with DNA sequencing.

Appropriate therapeutic solutions against Staphylococcal infections are currently limited. To work out the complex task of challenging drug resistance in Staphylococcus aureus, new compounds with novel modes of action are required. In this study, we performed target-driven virtual screening to filter exhaustive phytochemical libraries that can inhibit the activity of S. aureus DNA Gyrase B (Gyr B). Three top-ranked hit molecules (Mangostenone E, Candenatenin A and 2,4,4'-trihydroxydihydrochalcone) were identified from comprehensive molecular docking studies based on their strong spatial affinity with key catalytic residues of the binding pocket of DNA GyrB, especially with the well-known crucial residue Asp81. Molecular dynamics (MD) simulations were performed for these identified hit molecules for better understanding of their dynamical and structural profiles throughout the MD simulations. These compounds can be explored as future lead optimization molecules to discover a new class of antibiotics against resistant Staphylococcus aureus strains. (C) 2018 Published by Elsevier Inc.