An additional ionic bond suggested by molecular modelling of TEM-2 might induce a slight discrepancy between catalytic properties of TEM-1 and TEM-2 β-lactamases (original) (raw)
2000, FEMS Microbiology Letters
The plasmid-mediated TEM-I and TEM-2 p-lactamases are the most commonly encountered among Gram-negative bacteria. They belong to molecular class A, and differ by one amino acid at position 39 : TEM-1 have a glutamine and TEM-2 a lysine. Kinetic parameters (& and I&) and catalytic efftciency (k,,JK,,,) of TEM-1 and TEM-2 P-lactamases are slightly, but significantly different. For all antibiotics except methicillin and cefazolin, the catalytic efficiency values of TEM-2 are clearly greater than that of TEM-1. Molecular modelling of TEM-2, when compared to that of TEM-1, showed an additional ionic bond between Lys-39 and Glu-281.
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Drifted catalytic properties of β-lactamases due to unconstrained use of antibiotics
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Drifted catalytic properties of β-lactamases due to unconstrained use of antibiotics
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The diversity of the catalytic properties of class A β-lactamases
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FEMS Microbiology Letters, 2000
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Journal of Biological Chemistry, 1999
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FEBS open bio, 2018
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