Growth of L. biflexa hklep and rrlep mutant strains in EMJH medium. A. The rrlep and hklep mutants grew as well as the wild-type strain (wt) in EMJH liquid medium supplemented with hemin or δ-aminolevulinic acid (ALA). However, the mutants did not grow in EMJH liquid medium. B. Complementation of the L. biflexa rrlep mutant. Transformation of L. biflexa rrlep mutant with the empty shuttle vector and the shuttle vector carrying the L. biflexa rrlep gene plated onto EMJH and EMJH supplemented with hemin. The growth of the rrlep mutant complemented by the rrlep wild type gene was similar to the wild type growth onto EMJH plates. Strains were incubated at 30°C for one week.