This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
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...) |
|||
| Line 1: | Line 1: | ||
| - | [[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== | ||
| Line 14: | Line 14: | ||
[[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]] | ||
| Line 27: | Line 27: | ||
[[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
|
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
Page seeded by OCA on Thu Feb 21 15:29:32 2008
