Sandbox Reserved 994: Difference between revisions

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== Hydrolysis Mechanism ==
== Hydrolysis Mechanism ==
[[Image:B-lactam hydrolysis3.png]]


[[Image:B-lactam hydrolysis3.png|500px|left|thumb|alt=text|caption]]
[[Image:B-lactam hydrolysis3.png|500px|left|thumb|alt=text|β-lactam antibiotics (basic structure of a β-lactam is shown above) are hydrolyzed by β-lactamase enzymes, utilizing a covalent catalysis serine-based mechanism. The β-lactamase cleaves the amide bond of the four membered ring which renders the antibiotic inactive before it reaches its bacterial target, the transpeptidase enzymes.]]


β-lactam antibiotics are hydrolyzed by β-lactamase enzymes, utilizing a covalent catalysis serine-based mechanism, rendering the antibiotic inactive before it reaches its bacterial target, the transpeptidase enzymes.  
[[Image:Beta-lactamase resized mechanism.png|500px|left|thumb|alt=text|The mechanism of attack involves a catalytic serine residue, a carboxylated lysine, and another active site serine which contributes to proton movement (A). A high energy tetrahedral intermediate (B) is generated and an acyl enzyme intermediate (C) is formed after the cleavage of the four-membered ring. KCX84 activates the deacylating water which completes the reaction leaving a hydrolyzed β-lactam ring and a regenerated β-lactamase.<ref>DOI: 10.1021/ar300327a</ref>]]


[[Image:Beta-lactamase resized mechanism.png]]
The mechanism of attack involves a catalytic serine residue, a carboxylated lysine, and another active site serine which contributes to proton movement (A). A high energy tetrahedral intermediate (B) is generated and an acyl enzyme intermediate (C) is formed after the cleavage of the four-membered ring. KCX84 activates the deacylating water which completes the reaction leaving a hydrolyzed β-lactam ring and a regenerated β-lactamase.<ref>DOI: 10.1021/ar300327a</ref>


<scene name='69/691536/Closeupdrug/1'>close up</scene><ref>PMID: 10817708</ref>
<scene name='69/691536/Closeupdrug/1'>close up</scene><ref>PMID: 10817708</ref>