The ShBle resistance determinant from Streptoalloteichus hindustanus is expressed in Haloferax volcanii and confers resistance to bleomycin

We have designed a gene cassette for expression of the bleomycin-resistance protein from Streptoalloteichus hindustanus (ShBle) in the extremely halop hilic archaeon Haloferax volcanii, and shown that transformed haloarchaea a re resistant to bleomycin. Recombinant ShBle was purified by a one-step aff inity-chromatography procedure as a correctly folded, dimeric protein. ShBl e thus provides a useful haloarchaeal selectable marker and represents the first non-halophilic and soluble heterologous protein to be expressed in th e Haloarchaea.