pump. The deduced amino acid sequences encoded by the three genes involved show a resemblance to proteins known in proton-dependent multidrug efflux systems (11). But the solvent pump differs from the drug pumps because it does not pump antibiotics (12).
Now the genes for the efflux pump have been cloned, it is possible to transfer them into other bacteria. Transfer of the srpABC genes to the solvent sensitive P. putida PPO200 strain resulted in acquisition of solvent resistance by this organism (10). The demonstration that it is possible to transfer the cloned genes for the efflux pump to another P. putida strain with the concomitant gain of solvent resistance by that organisms has far reaching implications for industrial applications in the fine chemistry area.
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