Selection of Ampicillin-Resistant Transformants: Isolates colonies carrying AmpR plasmids after chemical or electroporation transformation of Escherichia coli.

Plasmid Cloning and Maintenance: Maintains plasmid-bearing E. coli strains on solid media under 100 µg/mL ampicillin selection.

Blue-White Screening: Screens recombinant clones on Amp plates supplemented with X-gal/IPTG using lacZα-complementation in E. coli.

Colony Isolation and Purification: Streaks for single colonies to purify AmpR E. coli strains from mixed cultures.

Colony Counting (CFU Enumeration): Quantifies viable AmpR E. coli cells following transformations or dilution plating.

Colony PCR and Sequencing Prep: Provides colonies for rapid PCR screening and downstream Sanger/NGS verification.

Library Construction and Screening: Selects plasmid-based genomic or cDNA libraries maintained in AmpR E. coli.

Expression Construct Screening: Verifies AmpR expression plasmids from colonies prior to liquid culture induction.

Replica Plating and Stability Testing: Assesses plasmid retention and antibiotic dependence in E. coli across passages.

Conjugation/Transduction Selection: Selects recipients carrying AmpR plasmids after mating or phage transduction in E. coli.