Inducible-Expression Plasmid for Rhodobacter sphaeroides and Paracoccus denitrificans▿ †

We have developed a stable isopropyl-β-d-thiogalactopyranoside (IPTG)-inducible-expression plasmid, pIND4, which allows graduated levels of protein expression in the alphaproteobacteria Rhodobacter sphaeroides and Paracoccus denitrificans. pIND4 confers kanamycin resistance and combines the stable replicon of pMG160 with the lacIq gene from pYanni3 and the lac promoter, PA1/04/03, from pJBA24