1nzd: Difference between revisions
New page: left|200px<br /><applet load="1nzd" size="450" color="white" frame="true" align="right" spinBox="true" caption="1nzd, resolution 2.Å" /> '''T4 phage BGT-D100A mut... |
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[[Image:1nzd.jpg|left|200px]]<br /><applet load="1nzd" size=" | [[Image:1nzd.jpg|left|200px]]<br /><applet load="1nzd" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1nzd, resolution 2.Å" /> | caption="1nzd, resolution 2.Å" /> | ||
'''T4 phage BGT-D100A mutant in complex with UDP-glucose: Form I'''<br /> | '''T4 phage BGT-D100A mutant in complex with UDP-glucose: Form I'''<br /> | ||
==Overview== | ==Overview== | ||
T4 phage beta-glucosyltransferase (BGT) is an inverting | T4 phage beta-glucosyltransferase (BGT) is an inverting glycosyltransferase (GT) that transfers glucose from uridine diphospho-glucose (UDP-glucose) to an acceptor modified DNA. BGT belongs to the GT-B structural superfamily, represented, so far, by five different inverting or retaining GT families. Here, we report three high-resolution X-ray structures of BGT and a point mutant solved in the presence of UDP-glucose. The two co-crystal structures of the D100A mutant show that, unlike the wild-type enzyme, this mutation prevents glucose hydrolysis. This strongly indicates that Asp100 is the catalytic base. We obtained the wild-type BGT-UDP-glucose complex by soaking substrate-free BGT crystals. Comparison with a previous structure of BGT solved in the presence of the donor product UDP and an acceptor analogue provides the first model of an inverting GT-B enzyme in which both the donor and acceptor substrates are bound to the active site. The structural analyses support the in-line displacement reaction mechanism previously proposed, locate residues involved in donor substrate specificity and identify the catalytic base. | ||
==About this Structure== | ==About this Structure== | ||
1NZD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacteriophage_t4 Bacteriophage t4] with CL, UPG and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA_beta-glucosyltransferase DNA beta-glucosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.27 2.4.1.27] Full crystallographic information is available from [http:// | 1NZD is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacteriophage_t4 Bacteriophage t4] with <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=UPG:'>UPG</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA_beta-glucosyltransferase DNA beta-glucosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.27 2.4.1.27] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NZD OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: udp-glucose]] | [[Category: udp-glucose]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:11:41 2008'' | ||
Revision as of 15:11, 21 February 2008
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T4 phage BGT-D100A mutant in complex with UDP-glucose: Form I
OverviewOverview
T4 phage beta-glucosyltransferase (BGT) is an inverting glycosyltransferase (GT) that transfers glucose from uridine diphospho-glucose (UDP-glucose) to an acceptor modified DNA. BGT belongs to the GT-B structural superfamily, represented, so far, by five different inverting or retaining GT families. Here, we report three high-resolution X-ray structures of BGT and a point mutant solved in the presence of UDP-glucose. The two co-crystal structures of the D100A mutant show that, unlike the wild-type enzyme, this mutation prevents glucose hydrolysis. This strongly indicates that Asp100 is the catalytic base. We obtained the wild-type BGT-UDP-glucose complex by soaking substrate-free BGT crystals. Comparison with a previous structure of BGT solved in the presence of the donor product UDP and an acceptor analogue provides the first model of an inverting GT-B enzyme in which both the donor and acceptor substrates are bound to the active site. The structural analyses support the in-line displacement reaction mechanism previously proposed, locate residues involved in donor substrate specificity and identify the catalytic base.
About this StructureAbout this Structure
1NZD is a Single protein structure of sequence from Bacteriophage t4 with , and as ligands. Active as DNA beta-glucosyltransferase, with EC number 2.4.1.27 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of the T4 phage beta-glucosyltransferase and the D100A mutant in complex with UDP-glucose: glucose binding and identification of the catalytic base for a direct displacement mechanism., Lariviere L, Gueguen-Chaignon V, Morera S, J Mol Biol. 2003 Jul 25;330(5):1077-86. PMID:12860129
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