Isolation of the rstA gene as a multicopy suppressor of YjeE, an essential ATPase of unknown function in Escherichia coli

Abstract

YjeE is an essential ATPase in Escherichia coli whose cellular function remains uncharacterized. Using a genomic library, we have identified rstA as a multicopy suppressor of a conditional yjeE deletion strain. High-copy rstA is the first recorded suppressor for a lesion in yjeE, and this newly charted genetic interaction has the potential to be informative about the function, with further study of the interacting partners.

FIG. 1.

Identification of the gene responsible for the suppression of the yjeE lethal phenotype. The shaded areas indicate sequences that are present on the plasmids. The pGEM-long and pGEM-short plasmids were isolated from a random genomic library. pBF9-rstA was constructed by cloning rstA between the NdeI and HindIII sites on the pBF9 vector.

FIG. 2.

Arabinose dependence of the conditional mutant strain EB444 compared with the multicopy suppressor strains. (A) Strains were grown on solid medium overnight at 37°C. The left plate shows EB444, with each plasmid grown in the presence of arabinose, and the right plate shows the same strains in the absence of arabinose. (B) Strains were grown in M9 liquid medium at 37°C with shaking at 250 rpm. ⧫, EB444; ▪, EB444 with 0.2% arabinose; ▴, EB444(pBF9-rstA); ×, EB444(pBF9-rstA) with 0.2% arabinose.