Sandbox Reserved 992: Difference between revisions
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Class C β-lactamases share a very similar mechanism as the Class A β-lactams, acylation followed by hydrolytic deacylation.4 Class C differs from A in that the hydrolytic water, activated by tyrosine 150, approaches the enzyme from the opposite side. This activated water is what allows β-lactamases to deacylation and maintain their catalytic function, while PBPs cannot.<ref name="Bush 2013" /> | Class C β-lactamases share a very similar mechanism as the Class A β-lactams, acylation followed by hydrolytic deacylation.4 Class C differs from A in that the hydrolytic water, activated by tyrosine 150, approaches the enzyme from the opposite side. This activated water is what allows β-lactamases to deacylation and maintain their catalytic function, while PBPs cannot.<ref name="Bush 2013" /> | ||
[[Image:Beta lactamase mechaism.jpg | [[Image:Beta lactamase mechaism.jpg|thumb|center|Class C β-lactamase general mechanism, showing covalently bound β-lactam antibiotic in intermidiate state.]] | ||
Class C β-lactamases, among many other enzyme types, also contain a structural component known as an oxyanion hole. This pocket of hydrophilic residues directly stabilizes the high-energy tetrahedral intermediate, lowering the activation energy and promoting a faster overall reaction.<ref>Albert Lehninger et al. (2008). Principles of Biochemistry (5th ed.). Macmillan. p. 207.</ref><ref>Livermore, David. β-Lactamase mediated resistance and opportunities for its control. J. Antimicrob. Chemother. (1998) 41 (suppl 4): 25-41.</ref> | Class C β-lactamases, among many other enzyme types, also contain a structural component known as an oxyanion hole. This pocket of hydrophilic residues directly stabilizes the high-energy tetrahedral intermediate, lowering the activation energy and promoting a faster overall reaction.<ref>Albert Lehninger et al. (2008). Principles of Biochemistry (5th ed.). Macmillan. p. 207.</ref><ref>Livermore, David. β-Lactamase mediated resistance and opportunities for its control. J. Antimicrob. Chemother. (1998) 41 (suppl 4): 25-41.</ref> | ||