This subfamily of drug efflux proteins, a part of the major faciliator family, is predicted to have 12 membrane-spanning regions. Members with known activity include Bcr (bicyclomycin resistance protein) in E. coli, Flor (chloramphenicol and florfenicol resistance) in Salmonella typhimurium DT104, and CmlA (chloramphenicol resistance) in Pseudomonas sp. plasmid R1033.
Jiyao W et al.(2023). "The conserved domain database in 2023.",