RecX alone, or in concert with RecO or RecF, plays an important role in chromosomal and plasmid transformation.

The metB5 locus contains a single point mutation.
aThe yield of met+ transformants (SB19 DNA, chromosomal transformation) and
bkanamycin resistant transformants (pUB110, plasmid transformation) was corrected for DNA uptake and cell viability, and the values obtained normalized relative to that of the rec+ strain, taken as 100. Between parentheses is included the number of transformants/cell.
cThe transformation frequencies of rec+, recF15, ΔrecR, ΔrecO, recX342 (previously termed recH342), recX342 ΔrecR, recX342 recF15, recX342 ΔrecO, recX342 ΔrecR and ΔrecA cells were reported elsewhere [13], [15], [16], [52] and determined here for direct comparison. The results are the average of at least three independent experiments and are within a 10% standard error.