Table 3.

Sites of transposon insertion in selected copper genes in pXccCu2 from X. citri subsp. citri A44 and the effect of mutagenesis on the level of copper resistance

MutantRegion mutatedMutation site in the gene (bp)Gene size (bp)Portion deleted (%)Tolerated concn of copper (mg liter−1)a
M60Upstream of cop genes1,029 upstream of copL300
M114Upstream of cop genes717 upstream of copL300
M257Hypothetical repressor1632795300
M357copL264209450
M377copL401420550
M206Between copL and copA2 upstream of copA50
M122copA6591,8726550
M08copA7881,8725850
M06copA11901,8723650
M167copA13891,8722650
M125copA18211,872350
M169copB1131,2699175
M160copB3761,2697075
M46copB6471,2694975
M10copB8171,2693675
M120copM9077188200
M48copM13877182200
M149copG6752587300
M155copG27152548300
M89copG5055254300
M159copC34138411300
M101copD19493079300
M98copD68693026300
  • a Maximum tolerated concentration of copper, as copper sulfate pentahydrate, added to mannitol-glutamate-yeast extract (MGY) agar.