Table 2

Muropeptide compositions of peptidoglycans from E. coli MG1655 carrying pBGS18-pCT (plasmid alone, control strain) and different β-lactamasesa

SamplebRelative abundance (mol%)cCross-linkage (%)Chain length
MonomersDimersTrimersLppAnhydrous formsPentapeptides
MG(pBGS18-pCT)61.0 ± 0.836.1 ± 0.82.9 ± 0.118.0 ± 0.48.6 ± 1.40.3 ± 0.242.0 ± 0.911.9 ± 2
MG(pBTEM-1)62.9 ± 2.834.9 ± 3.22.8 ± 0.316.1 ± 2.98.4 ± 1.10.8 ± 0.0640.5 ± 3.712 ± 1.5
MG(pBTEM-29)62.8 ± 2.633.5 ± 3.43.8 ± 0.814.8 ± 4.110.9 ± 1.10.5 ± 0.0241.1 ± 1.89.2 ± 0.9
MG(pBCTX-M-32)63.1 ± 0.234 ± 0.32.7 ± 0.0314.1 ± 0.97.0 ± 0.040.2 ± 0.0239.6 ± 0.114.3 ± 0.07
MG(pBCTX-M-8)64 ± 0.433.6 ± 0.52.4 ± 0.0313.1 ± 1.85.4 ± 0.30.23 ± 0.0138.4 ± 0.418.3 ± 1.0
MG(pBCTX-M-2)63.3 ± 0.533.7 ± 0.42.9 ± 0.914.9 ± 1.76.4 ± 0.20.3 ± 0.139.7 ± 1.315.7 ± 0.5
MG(pBCTX-M-14)62.5 ± 0.534.8 ± 0.32.7 ± 0.215.6 ± 2.16.9 ± 0.70.1 ± 0.00140.3 ± 0.714.7 ± 1.5
MG(pBSFO1)61.3 ± 1.335.1 ± 0.73.7 ± 0.615.4 ± 0.912.1 ± 30.5 ± 0.342.4 ± 1.98.8 ± 2.8
MG(pBAmpR-SFO1)68.7 ± 0.229.4 ± 0.21.9 ± 0.0212.7 ± 0.013.3 ± 0.10.1 ± 0.0233.3 ± 0.229.8 ± 1.2
MG(pBVIM-1)61.2 ± 2.135.8 ± 1.52.9 ± 0.615.5 ± 2.36.4 ± 1.00.2 ± 0.141.8 ± 2.715.9 ± 2.5
MG(pBFOX-4)63.7 ± 0.533.8 ± 0.72.4 ± 0.212.2 ± 1.65.8 ± 0.10.3 ± 0.0438.6 ± 0.417.2 ± 0.3
MG(pBOXA-10-like)65.9 ± 0.131.8 ± 0.12.3 ± 0.0212.2 ± 0.14.9 ± 0.80.2 ± 0.236.3 ± 0.120.7 ± 3
MG(pBOXA-24)68.9 ± 128.8 ± 0.92.2 ± 0.212.2 ± 2.33.6 ± 0.20.1 ± 0.0333.3 ± 1.228.1 ± 0.5
MG(pBGS18-pCT)d69.5 ± 0.728.3 ± 0.62.3 ± 0.1211.8 ± 1.354.3 ± 0.10.1 ± 0.132.8 ± 0.823.4 ± 0.7
MG(pBTEM-1)d68.1 ± 0.229.4 ± 0.42.5 ± 0.213.3 ± 0.64.9 ± 0.30.1 ± 0.134.4 ± 0.120.5 ± 1.2
MG(pBAmpR-SFO1)d69.1 ± 1.628.7 ± 1.52.3 ± 0.212.1 ± 1.34.9 ± 0.70.1 ± 0.0433.2 ± 1.820.5 ± 2.8
MG(pBVIM-1)d69.2 ± 1.028.4 ± 0.62.35 ± 0.411.9 ± 0.94.5 ± 1.80.1 ± 0.0133.2 ± 1.320.1 ± 3.7
MG(pBOXA-10-like)d74.2 ± 5.925.9 ± 2.82.4 ± 0.511.6 ± 0.64.8 ± 2.20.07 ± 0.0132.6 ± 0.821.5 ± 3.5
MG(pBOXA-24)d69.2 ± 0.828.5 ± 0.52.3 ± 0.39.9 ± 3.03.8 ± 0.20.2 ± 0.133.1 ± 1.126.5 ± 1.2
  • a Values are means and standard deviations from three independent experiments. Boldface indicates the isolates in which changes in the PG composition have been described.

  • b Peptidoglycan of E. coli MG1655 transformed with the indicated plasmid.

  • c Muropeptides are grouped according to structural similarities, differences in PG composition, and structure of strains.

  • d Data were obtained without the presence of imipenem.