Characterize the growth kinetics (lag time, maximum specific growth rate, and final yield) of Staphylococcus aureus across sub-inhibitory oxacillin concentrations using continuous OD600 monitoring in a plate reader, to quantify dose-dependent growth suppression.
Determine the minimum inhibitory concentration (MIC) of ciprofloxacin against clinical and reference Escherichia coli isolates using the CLSI reference broth microdilution method to assign susceptible/intermediate/resistant categories.
Enumerate viable Klebsiella pneumoniae over time during gentamicin exposure using the Miles-Misra drop-plate CFU method to construct a time-kill curve and determine bactericidal activity (>=3 log10 reduction) relative to a no-drug control.
Quantify the horizontal transfer frequency of the broad-host-range conjugative plasmid RP4 (RK2) from a donor E. coli strain to a chromosomally marked recipient using a solid-surface filter-mating assay with selective plating to enumerate transconjugants per recipient.
Quantify in vitro biofilm biomass formed by Pseudomonas aeruginosa PAO1 on polystyrene using the crystal violet (CV) staining assay, and compare biofilm formation under a test condition (e.g., sub-inhibitory antibiotic or mutant strain) versus wild-type baseline.