Antibiotic Selection of Transformants: Selects chloramphenicol-resistant colonies of E. coli and other Enterobacteriaceae carrying cat-marked plasmids.

BAC/Low-Copy Plasmid Maintenance: Supports stable propagation of BACs and low/medium-copy vectors (e.g., pACYC derivatives) at 12.5 µg/mL chloramphenicol.

Clone Screening from Single Colonies: Enables colony picking for downstream colony PCR, restriction analysis, or sequencing of chloramphenicol-resistant clones.

Strain Engineering with cat Cassettes: Selects recombinants after recombineering or CRISPR editing using chloramphenicol resistance markers in E. coli.

Conjugation/Transposition Selection: Recovers transconjugants or transposon insertions carrying cat in E. coli, Salmonella enterica, and related species.

Plasmid Stabilization During Subculturing: Maintains selective pressure to preserve cat-bearing plasmids during routine streaking and passaging.

Genomic Library Plating: Plates BAC and plasmid libraries that use chloramphenicol selection for clone recovery.

Shuttle Vector Selection in Gram-Positive Hosts: Selects cat-marked constructs in organisms such as Bacillus subtilis and Staphylococcus aureus when using LB-based media.