TABLE 3.

Correlation between mutations in purported regulatory genes and target gene expression

Group and isolateRibotypeAmpR amino acid substitutionInducible AmpCExpression of ampC mRNAaMutation(s) in:Expression of mexA mutationaMexT amino acid substitutionExpression of mexE mutationaMexZ amino acid substitutionExpression of mexX mutationa
MexRNalCNalD
Group 1
    AM602JGly283→Glu; Met288→ArgNo29Val126→GluGly71→Glu; Ala145→Val; Ser209→ArgHis154→Pro; deletion Pro155 through Thr1583.5Leu26→Val0.19None0.06
FI506HNoneYes66NoneGly71→GluNone0.72Leu26→Val0.01Leu138→Arg; Leu196→Ile0.95
BK546ANoneNo480NoneGly71→Glu; Ser209→ArgNone0.52Leu26→Val; partialb0.20Insert His-Gly between Gly50→His516.7
HW311ANoneNo970NoneGly71→Glu; Ser209→ArgPro196→Gln2.8Leu26→Val; partial0.01None19
DB322ANoneNo2,400NoneGly71→Glu; Ser209→ArgInsert Ile between Ile15-Leu163.5Leu26→Val; partial0.22Insert His-Gly between Gly50→His5120
AM339EGlu114→Ala; Gly283→Glu; Met288→ArgNo290Val126→GluGly71→Glu; Ala145→Val; Ser209→ArgCys149→Arg5.0Leu26→Val0.66Arg13→Gln23
BK553ANoneNo610NoneGly71→Glu; Ser209→ArgNone0.41Leu26→Val; partial0None24
BK501ANoneNo930NoneGly71→Glu; Ser209→ArgNone1.4Leu26→Val; partial0.76Insert His-Gly between Gly50→His5129
AM609INoneYes2,600Val126→GluGly71→GluNone1.9Leu26→Val0.05Leu128→Met29
BK545ANoneNo270NoneGly71→Glu; Ser209→ArgNone1.1Leu26→Val; partial0.24Insert His-Gly between Gly50→His5132
DB513NNoneYes1,500Val126→GluGly71→Glu; frameshift at Gln162None3.1Leu26→Val0.60None43
CK575FNoneYes170NoneGly71→Glu; Ser209→ArgNone0.88Leu26→Val0.41Tyr49→Stop53
DB537ANoneNo380NoneGly71→Glu; Ser209→ArgNone0.87Leu26→Val; partial0Insert His-Gly between Gly50→His5188
Group 2
CK505CArg244→Trp; Gly273→GluYes0.70NoneGly71→Glu; Ser209→ArgNone1.5Leu26→Val1.1None13
UL118CArg244→Trp; Gly273→GluYes1.3NoneGly71→Glu; Ser209→ArgNone0.96Leu26→Val0None9.6
CK558DNoneYes2.0Val126→Glu; Val132→ArgGly71→Glu; Ser209→ArgNone1.0Leu26→Val1.4Frameshift at Ala4718
UL517EGlu114→Ala; Gly283→Glu; Met288→ArgYes2.4Val126→GluGly71→Glu; Ala145→Val; Ser209→ArgNone0.90Leu26→Val1.8Arg13→Gln3.8
BK555GNoneYes2.4Val126→GluGly71→GluNone1.6Leu26→Val0None31
CK550DNoneYes6.2Val126→Glu; Val132→ArgGly71→Glu; Ser209→ArgNone1.4Leu26→Val2.8None73
Group 3a
MD519ONoneYes2.1NoneGly71→Glu; Ser209→ArgAsp147→Asn1.0Leu26→Val0.23Frameshift at Arg15835
MD504PNoneYes1.8NoneGly71→Glu; Ser209→ArgNone1.8Leu26→Val0.65None5.7
CK516RGlu114→Ala; Ile251→Val; Gly283→Glu; Met288→ArgYes3.5NoneGly71→Glu; Ser209→ArgNone2.6Leu26→Val0.66None1.1
MD521QGlu114→Ala; Ile251→Val; Gly283→Glu; Met288→ArgYes3.8NoneGly71→Glu; Ser209→ArgNone1Leu26→Val0.67Ala35→Val1.1
    CK503SNoneYes4.0NoneGly71→Glu; Ser209→ArgNone1.8Leu26→Val1.7None4.0
DB504ANoneYes7.5NoneGly71→Glu; Ser209→ArgNone1.4Leu26→Val0.71None4.4
Group 3b
MD119MNoneYes2.7NoneNoneNone2.4Leu26→Val0None5.7
CK188BNoneYes0.31NoneGly71→Glu; Ser209→Arg; Pro210→LeuThr188→Ala3.9Leu26→Val0.43None5.8
CK140BNoneYes5.5NoneGly71→Glu; Ser209→Arg; Pro210→LeuThr188→Ala2.2Leu26→Val0.21None6.9
MD104BNoneYes0.41NoneGly71→Glu; Ser209→ArgNone2.2Leu26→Val0.55None16
UL140LGlu114→Ala; Gly283→Glu; Met288→ArgYes5.1Val126→GluGly71→Glu; frameshift at Ala145None13Leu26→Val1.6Tyr49→Stop330
AM128KGly283→Glu; Met288→ArgYes3.6Val126→GluGly71→Glu; Ser209→ArgNone0.71Leu26→Val0.41Leu138→Arg2.8
MD510CArg244→Trp;Gly273→GluYes2.6NoneGly71→GluNone0.97Leu26→Val0.40None5.0
DB311DNoneYes1.4Val126→Glu; Val132→ArgGly71→Glu; Ser209→ArgNone1.7Leu26→Val1.2None6.6
ATCC 27853NoneYes1NoneGly71→Glu; Ser209→ArgNone1Leu26→Val1None1
  • a Relative to the expression of P. aeruginosa ATCC 27853, which is assigned a value of 1. Only the initial 462 bp could be amplified and sequenced.

  • b Only the initial 462 bp could be amplified and sequenced.