Sandbox 78: Difference between revisions
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== Function == | == Function == | ||
[[Image:Hydrolysis triacylglycerol reaction.png|300px|left|thumb| Hydrolysis of triacylglycerol.]] | [[Image:Hydrolysis triacylglycerol reaction.png|300px|left|thumb| Hydrolysis of triacylglycerol. This reaction is catalyzed by HGL.]] | ||
As an esterase with a catalytically active serine, HGL exhibits an established serine esterase mechanism. The active serine is facilitated first by the neighboring formation of a salt bridge between Asp-136 and His-152, which induces the appropriation of a proton from Ser-153. The now highly nucleophilic Ser-153 will attack the carbonyl carbon of the acetate group in a triacylglycerol molecule. The now tetrahedral species, stabilized by the oxyanion hole; however, as soon as the species disassembles into the covalently bonded acetate and lipase, and the serine undergoes deacylation where water acts at the hydroxyl group. This final step restores Ser-153 to its protonated state<ref name="esterase">PMID:23209280</ref>. | As an esterase with a catalytically active serine, HGL exhibits an established serine esterase mechanism. The active serine is facilitated first by the neighboring formation of a salt bridge between Asp-136 and His-152, which induces the appropriation of a proton from Ser-153. The now highly nucleophilic Ser-153 will attack the carbonyl carbon of the acetate group in a triacylglycerol molecule. The now tetrahedral species, stabilized by the oxyanion hole; however, as soon as the species disassembles into the covalently bonded acetate and lipase, and the serine undergoes deacylation where water acts at the hydroxyl group. This final step restores Ser-153 to its protonated state<ref name="esterase">PMID:23209280</ref>. | ||