TABLE 2

The viability of E. coli strains carrying point mutations or deletions of recA, recBCD, and/or recF genes

Strain	Relevant genotype	Viability^a
Point mutants
AB1157	Rec+^b	100.0 ± 2.8
JC2926	recA13	47.6 ± 3.8
JC5519	recB21 recC22	27.7 ± 1.9
JC5547	recA13 recB21 recC22	18.0 ± 1.7
Deletions
AB1157	Rec+^b	93.8 ± 4.7
JC10287	ΔrecA304	46.0 ± 2.4
JB1	ΔrecBCD	27.8 ± 2.3
AM1	ΔrecA304 ΔrecBCD	18.8 ± 1.9
AM3	ΔrecF	70.8 ± 5.2
AM4	ΔrecA304 ΔrecF	45.6 ± 4.0
AM5	ΔrecBCD ΔrecF	29.6 ± 7.9

↵^a Viability is expressed as mean ± standard error. The number of independent measurements, done on different days, is between 8 and 20.
↵^b Both strains are AB1157, but the data were collected at different times and treated separately.