TABLE 2.

relE homologues

Bacterial species	relE genea	Characteristic of the RelE protein
		No. of aa	Molecular mass (kDa)b	pIb
Gram-negative bacteria
E. coli K-12	relEK-12	95	11.2	9.7
E. coli K-12	relESOSc	92	10.8	9.5
E. coli plasmid P307	relEP307	95	11.2	9.9
E. coli plasmid pB171	relEpB171	95	11.1	10.7
Salmonella enteria serovar Typhi	relEStyphi1	94	10.9	10.4
P. shigelloides plasmid p11184	relEPs	94	11.2	10.7
Haemophilus influenzae	relEHi	102	11.9	6.7
Vibrio cholerae	relEVc	96	11.2	9.9
Helicobacter pylori	relEHp1	88	10.4	7.9
H. pylori	relEHp2	90	10.4	10.2
Butyrivibrio fibrisolvens	relEBf	93	11.0	9.7
Acetobacter europaeus	relEAe	93	10.9	10.0
Morganella morganii	relEMm	93	11.0	10.9
Thiobacillus ferrooxidans	relETf	90	10.3	10.8
Aquifex aeolicusd	relEAq	89	10.4	10.8
Synechosystisd	relESy	120	13.7	7.9
Gram-positive bacteria
Bacillus thuringiensis	relEBt	74	8.6	9.7
Mycobacterium tuberculosis	relEMt1	87	10.2	11.0
M. tuberculosis	relEMt2	97	11.1	9.5
Streptococcus pneumoniae	relESp1	92	10.9	10.3
S. pneumoniae	relESp2	87	10.4	11.1
Archaea
Methanococcus jannaschii	relEMj1	90	11.0	10.2
Archaeoglobus fulgidus	relEAf1	87	10.6	10.3
A. fulgidus	relEAf2	92	11.0	9.9
A. fulgidus	relEAf3	85	10.0	10.0
A. fulgidus	relEAf4	86	10.2	9.9
P. horikoshii OT3	relEPyr	90	10.9	10.9

^aSubscripts refer to the species in which the relE genes were identified (see the species shown in the leftmost column). 

^bMolecular masses and isoelectric points were calculated by using the Wisconsin GCG package. 

^cThe relBE_SOS locus (dinJ - yafQ) of E. coli K-12 contains a LexA binding site in the promoter region, thus belonging to the SOS regulon (48). 

^dFor clarity, A. aeolicus and Synechosystis were grouped with the gram-negative bacteria.