Bcr/CflA drug resistance efflux transporter:
A family of putative resistance factors found in Orientia are the genes coding for the Bcr/CflA drug resistance efflux transporter family. These are a part of the family of efflux transporters related to tetracycline resistance (TetA) in various bacteria.
Bcr/CflA drug resistance efflux transporter genes in Orientia
The genomes of all members of Orientia that we have examined contain several genes showing various levels of homology with these efflux transporters.
One gene in particular shows significant homology to Bcr/CflA drug resistance efflux transporters in Rickettsia. Within the genome of the Boryong isolate, this gene occurs at positions 1823967 – 1825148.
A second Bcr/CflA drug resistance efflux transporter gene with weaker homology to Rickettsia occurs within the genome of the Boryong isolate at positions 1463464 – 1464663.
Comparing the two genes between 14 genomes of various members of O. tsutsugamushi showed that both genes are present in all genomes, and well as in the genome of O. chuto. Within O. tsutsugamushi, there is inter-isolate variation at both the nucleic acid and protein levels. The significance of this variation is currently unclear, but will be investigated. Additional genomes will also be examined in the future.