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.png|thumb|center|Class C β-lactamase general mechanism, showing covalently bound β-lactam antibiotic in intermidiate state.]] | [[Image:Beta lactamase mechaism.png|1000px|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.5 | 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.5 | ||