Sandbox Reserved 769: Difference between revisions
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Indole-3-glycerol-phosphate (IGP) is cleaved by the tryptophan synthase α-subunit (TSA) to indole and glyceraldehyde-3-phosphate (GDP) This is known as the α-reaction. The alpha reaction is reversible. Then indole is transported via a 30 Å intermolecular tunnel to the tryptophan synthase β-subunits (TSB) that catalyze the condensation of indole and serine to tryptophan. This is known as the β-reaction and it is a pyridoxal-5-phosphate (PLP) dependent reaction. <ref name="cite7">http://tryptophan.net/Trpsynthase/Tryptophan%20Synthase.html</ref> | Indole-3-glycerol-phosphate (IGP) is cleaved by the tryptophan synthase α-subunit (TSA) to indole and glyceraldehyde-3-phosphate (GDP) This is known as the α-reaction. The alpha reaction is reversible. Then indole is transported via a 30 Å intermolecular tunnel to the tryptophan synthase β-subunits (TSB) that catalyze the condensation of indole and serine to tryptophan. This is known as the β-reaction and it is a pyridoxal-5-phosphate (PLP) dependent reaction. <ref name="cite7">http://tryptophan.net/Trpsynthase/Tryptophan%20Synthase.html</ref> | ||
The substrates and ligands that bind to the various sites of tryptophan synthase cause conformational changes not only in that particular subunit, but also in the other subunits, making the complete mechanism cooperative. | |||
[[Image:TrpSyn.gif]] | |||
'''Active Sites''' | |||
[[Image:Active Site 2.gif]] | |||
α subunit reaction: The αGlu49 and αAsp60 are thought to be directly involved in the catalysis as shown. | |||
β subunit reaction: The βLys87, βGlu109, and βSer377 are thought to be directly involved in the catalysis as shown. | |||
==References== | ==References== | ||
<references /> | <references /> | ||
