Blue-White Screening: α-complementation of lacZ in transformed E. coli using X-Gal (60 µg/mL) and IPTG (0.1 mM) to distinguish recombinant (white) from non-recombinant (blue) colonies.

Beta-Lactam Selection: Plasmid selection and maintenance in E. coli via carbenicillin disodium salt (100 µg/mL) for bla-mediated resistance.

Cloning and Ligation Screening: Post-ligation plating to identify successful inserts by white colony selection on LB agar (1.0% tryptone, 0.5% yeast extract, 1.0% NaCl, 1.5% agar).

Library Construction: Genomic/cDNA library plating and recombinant clone identification using blue-white selection.

Colony PCR Workflows: Rapid verification of candidate white colonies for insert presence and size via colony PCR.

Competent Cell QC: Assessing transformation efficiency of E. coli strains by plating on selective, X-Gal/IPTG-containing media.

Reporter/Promoter Assays: Screening lac promoter-driven constructs where IPTG induces lacZ expression and X-Gal provides a chromogenic readout.

Vector Background Reduction: α-complementation controls to monitor empty vector background and optimize cloning conditions in E. coli.