C. Olano et al., TOPOLOGICAL STUDIES OF THE MEMBRANE COMPONENT OF THE OLEC ABC TRANSPORTER INVOLVED IN OLEANDOMYCIN RESISTANCE IN STREPTOMYCES-ANTIBIOTICUS, FEMS microbiology letters, 143(2-3), 1996, pp. 133-139
The OleC ABC transporter of Streptomyces antibioticus is constituted b
y an ATP-binding protein (OleC) and a hydrophobic protein (OleC5). Her
e we present experimental evidence demonstrating that the OleC5 protei
n is an integral membrane protein and we propose a topological model f
or its integration into the membrane. This model is based on the gener
ation of hybrid proteins between different regions of OleC5 and a Esch
erichia coli beta-lactamase (BlaM) and the determination of the minima
l inhibitory concentrations to ampicillin in these constructions. Fusi
ons were generated both by cloning specific fragments of oleC5 and by
creating ExoIII nested deletions of the gene. In the topological model
proposed there will be six alpha-helix transmembrane regions, two cyt
oplasmic and four periplasmic loops and a hydrophobic linker domain.