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.
1v82
From Proteopedia
(New page: 200px<br /> <applet load="1v82" size="450" color="white" frame="true" align="right" spinBox="true" caption="1v82, resolution 1.85Å" /> '''Crystal structure o...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1v82.gif|left|200px]]<br /> | + | [[Image:1v82.gif|left|200px]]<br /><applet load="1v82" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1v82" size=" | + | |
caption="1v82, resolution 1.85Å" /> | caption="1v82, resolution 1.85Å" /> | ||
'''Crystal structure of human GlcAT-P apo form'''<br /> | '''Crystal structure of human GlcAT-P apo form'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The HNK-1 carbohydrate epitope is found on many neural cell adhesion | + | The HNK-1 carbohydrate epitope is found on many neural cell adhesion molecules. Its structure is characterized by a terminal sulfated glucuronyl acid. The glucuronyltransferases, GlcAT-P and GlcAT-S, are involved in the biosynthesis of the HNK-1 epitope, GlcAT-P as the major enzyme. We overexpressed and purified the recombinant human GlcAT-P from Escherichia coli. Analysis of its enzymatic activity showed that it catalyzed the transfer reaction for N-acetyllactosamine (Galbeta1-4GlcNAc) but not lacto-N-biose (Galbeta1-3GlcNAc) as an acceptor substrate. Subsequently, we determined the first x-ray crystal structures of human GlcAT-P, in the absence and presence of a donor substrate product UDP, catalytic Mn(2+), and an acceptor substrate analogue N-acetyllactosamine (Galbeta1-4GlcNAc) or an asparagine-linked biantennary nonasaccharide. The asymmetric unit contains two independent molecules. Each molecule is an alpha/beta protein with two regions that constitute the donor and acceptor substrate binding sites. The UDP moiety of donor nucleotide sugar is recognized by conserved amino acid residues including a DXD motif (Asp(195)-Asp(196)-Asp(197)). Other conserved amino acid residues interact with the terminal galactose moiety of the acceptor substrate. In addition, Val(320) and Asn(321), which are located on the C-terminal long loop from a neighboring molecule, and Phe(245) contribute to the interaction with GlcNAc moiety. These three residues play a key role in establishing the acceptor substrate specificity. |
==About this Structure== | ==About this Structure== | ||
| - | 1V82 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with TLA as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Galactosylgalactosylxylosylprotein_3-beta-glucuronosyltransferase Galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.135 2.4.1.135] Full crystallographic information is available from [http:// | + | 1V82 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=TLA:'>TLA</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Galactosylgalactosylxylosylprotein_3-beta-glucuronosyltransferase Galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.135 2.4.1.135] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1V82 OCA]. |
==Reference== | ==Reference== | ||
| Line 30: | Line 29: | ||
[[Category: transferase]] | [[Category: transferase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:32:29 2008'' |
Revision as of 13:32, 21 February 2008
|
Crystal structure of human GlcAT-P apo form
Overview
The HNK-1 carbohydrate epitope is found on many neural cell adhesion molecules. Its structure is characterized by a terminal sulfated glucuronyl acid. The glucuronyltransferases, GlcAT-P and GlcAT-S, are involved in the biosynthesis of the HNK-1 epitope, GlcAT-P as the major enzyme. We overexpressed and purified the recombinant human GlcAT-P from Escherichia coli. Analysis of its enzymatic activity showed that it catalyzed the transfer reaction for N-acetyllactosamine (Galbeta1-4GlcNAc) but not lacto-N-biose (Galbeta1-3GlcNAc) as an acceptor substrate. Subsequently, we determined the first x-ray crystal structures of human GlcAT-P, in the absence and presence of a donor substrate product UDP, catalytic Mn(2+), and an acceptor substrate analogue N-acetyllactosamine (Galbeta1-4GlcNAc) or an asparagine-linked biantennary nonasaccharide. The asymmetric unit contains two independent molecules. Each molecule is an alpha/beta protein with two regions that constitute the donor and acceptor substrate binding sites. The UDP moiety of donor nucleotide sugar is recognized by conserved amino acid residues including a DXD motif (Asp(195)-Asp(196)-Asp(197)). Other conserved amino acid residues interact with the terminal galactose moiety of the acceptor substrate. In addition, Val(320) and Asn(321), which are located on the C-terminal long loop from a neighboring molecule, and Phe(245) contribute to the interaction with GlcNAc moiety. These three residues play a key role in establishing the acceptor substrate specificity.
About this Structure
1V82 is a Single protein structure of sequence from Homo sapiens with as ligand. Active as Galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase, with EC number 2.4.1.135 Full crystallographic information is available from OCA.
Reference
Structural basis for acceptor substrate recognition of a human glucuronyltransferase, GlcAT-P, an enzyme critical in the biosynthesis of the carbohydrate epitope HNK-1., Kakuda S, Shiba T, Ishiguro M, Tagawa H, Oka S, Kajihara Y, Kawasaki T, Wakatsuki S, Kato R, J Biol Chem. 2004 May 21;279(21):22693-703. Epub 2004 Mar 1. PMID:14993226
Page seeded by OCA on Thu Feb 21 15:32:29 2008
Categories: Galactosylgalactosylxylosylprotein 3-beta-glucuronosyltransferase | Homo sapiens | Single protein | Ishiguro, M. | Kajihara, Y. | Kakuda, S. | Kato, R. | Kawasaki, T. | Oka, S. | Shiba, T. | Tagawa, H. | Wakatsuki, S. | TLA | Glycocyltransferase | Glycoprotein | Hnk-1 epitope | Transferase
