1uxy
From Proteopedia
(New page: 200px<br /><applet load="1uxy" size="450" color="white" frame="true" align="right" spinBox="true" caption="1uxy, resolution 1.80Å" /> '''MURB MUTANT WITH SER...) |
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| - | [[Image:1uxy.jpg|left|200px]]<br /><applet load="1uxy" size=" | + | [[Image:1uxy.jpg|left|200px]]<br /><applet load="1uxy" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1uxy, resolution 1.80Å" /> | caption="1uxy, resolution 1.80Å" /> | ||
'''MURB MUTANT WITH SER 229 REPLACED BY ALA, COMPLEX WITH ENOLPYRUVYL-UDP-N-ACETYLGLUCOSAMINE'''<br /> | '''MURB MUTANT WITH SER 229 REPLACED BY ALA, COMPLEX WITH ENOLPYRUVYL-UDP-N-ACETYLGLUCOSAMINE'''<br /> | ||
==Overview== | ==Overview== | ||
| - | MurB catalyzes the second committed step in the synthesis of | + | MurB catalyzes the second committed step in the synthesis of peptidoglycan, a key component of the bacterial cell wall. The crystal structures of both a S229A mutant and wild-type MurB in the presence of the substrate enolpyruvyl-UDP-N-acetylglucosamine were solved and refined at 1.8 A resolution. The single point mutation of residue 229 from serine to alanine eliminated a hydroxyl group which has previously been proposed to play a critical role as a proton donor during the second half-reaction of MurB, namely, reoxidation of FADH2 and reduction of the enolpyruvyl substrate. The mutation also resulted in the loss of the water molecule-hydrogen bonded to the serine hydroxyl in the wild-type structure changing the hydrogen-bonding network with in the active site. Comparison of the wild-type and S229A mutant structures confirms that the dramatic kinetic defect of an approximately 10(7)-fold decrease observed for the Ser 229 Ala mutant in the second half-reaction [Benson, T.E., Walsh, C.T., & Massey, V. (1997) Biochemistry 36, 796-805] is a direct result of the loss of the serine hydroxyl moiety rather than other nonspecific active-site changes or general structural defects. |
==About this Structure== | ==About this Structure== | ||
| - | 1UXY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with FAD and EPU as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/UDP-N-acetylmuramate_dehydrogenase UDP-N-acetylmuramate dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.158 1.1.1.158] Full crystallographic information is available from [http:// | + | 1UXY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=FAD:'>FAD</scene> and <scene name='pdbligand=EPU:'>EPU</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/UDP-N-acetylmuramate_dehydrogenase UDP-N-acetylmuramate dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.158 1.1.1.158] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1UXY OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: UDP-N-acetylmuramate dehydrogenase]] | [[Category: UDP-N-acetylmuramate dehydrogenase]] | ||
| - | [[Category: Benson, T | + | [[Category: Benson, T E.]] |
| - | [[Category: Hogle, J | + | [[Category: Hogle, J M.]] |
| - | [[Category: Walsh, C | + | [[Category: Walsh, C T.]] |
[[Category: EPU]] | [[Category: EPU]] | ||
[[Category: FAD]] | [[Category: FAD]] | ||
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[[Category: peptidoglycan synthesis]] | [[Category: peptidoglycan synthesis]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:29:32 2008'' |
Revision as of 13:29, 21 February 2008
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MURB MUTANT WITH SER 229 REPLACED BY ALA, COMPLEX WITH ENOLPYRUVYL-UDP-N-ACETYLGLUCOSAMINE
Overview
MurB catalyzes the second committed step in the synthesis of peptidoglycan, a key component of the bacterial cell wall. The crystal structures of both a S229A mutant and wild-type MurB in the presence of the substrate enolpyruvyl-UDP-N-acetylglucosamine were solved and refined at 1.8 A resolution. The single point mutation of residue 229 from serine to alanine eliminated a hydroxyl group which has previously been proposed to play a critical role as a proton donor during the second half-reaction of MurB, namely, reoxidation of FADH2 and reduction of the enolpyruvyl substrate. The mutation also resulted in the loss of the water molecule-hydrogen bonded to the serine hydroxyl in the wild-type structure changing the hydrogen-bonding network with in the active site. Comparison of the wild-type and S229A mutant structures confirms that the dramatic kinetic defect of an approximately 10(7)-fold decrease observed for the Ser 229 Ala mutant in the second half-reaction [Benson, T.E., Walsh, C.T., & Massey, V. (1997) Biochemistry 36, 796-805] is a direct result of the loss of the serine hydroxyl moiety rather than other nonspecific active-site changes or general structural defects.
About this Structure
1UXY is a Single protein structure of sequence from Escherichia coli with and as ligands. Active as UDP-N-acetylmuramate dehydrogenase, with EC number 1.1.1.158 Full crystallographic information is available from OCA.
Reference
X-ray crystal structures of the S229A mutant and wild-type MurB in the presence of the substrate enolpyruvyl-UDP-N-acetylglucosamine at 1.8-A resolution., Benson TE, Walsh CT, Hogle JM, Biochemistry. 1997 Jan 28;36(4):806-11. PMID:9020778
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