Table 1.

Complementation of E. coli lysS lysU double mutants by genes encoding class I LysRS proteins

Plasmid	Growth conditions*
	30°C	40°C	40°C + Lys	42°C	42°C + Lys
pCBS1-Bs trpS	++	−	−	−	−
pKS-Ec lysS	++	+	+	±	±
pCBS1-Mm lysS	++	−	±	−	−
pCBS1-Bb lysS	++	+	+	−	−

++, growth after 24 h; +, growth after 48 h; ±, growth after 72 h; −, no growth. 

^*Growth was on Luria–Bertani agar (100 μg/ml ampicillin) with the addition of 5 mM l-lysine where indicated.