1gjw: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1gjw.jpg|left|200px]] | [[Image:1gjw.jpg|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_1gjw", creates the "Structure Box" on the page. | |||
You may change the PDB parameter (which sets the PDB file loaded into the applet) | |||
or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |||
or leave the SCENE parameter empty for the default display. | |||
--> | |||
| | {{STRUCTURE_1gjw| PDB=1gjw | SCENE= }} | ||
| | |||
}} | |||
'''THERMOTOGA MARITIMA MALTOSYLTRANSFERASE COMPLEX WITH MALTOSE''' | '''THERMOTOGA MARITIMA MALTOSYLTRANSFERASE COMPLEX WITH MALTOSE''' | ||
| Line 31: | Line 28: | ||
[[Category: Rice, D W.]] | [[Category: Rice, D W.]] | ||
[[Category: Roujeinikova, A.]] | [[Category: Roujeinikova, A.]] | ||
[[Category: | [[Category: Alpha-amylase]] | ||
[[Category: | [[Category: Maltosyltransferase]] | ||
[[Category: | [[Category: Transferase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 17:40:04 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 17:40, 2 May 2008
THERMOTOGA MARITIMA MALTOSYLTRANSFERASE COMPLEX WITH MALTOSE
OverviewOverview
Maltosyltransferase (MTase) from the hyperthermophile Thermotoga maritima represents a novel maltodextrin glycosyltransferase acting on starch and malto-oligosaccharides. It catalyzes the transfer of maltosyl units from alpha-1,4-linked glucans or malto-oligosaccharides to other alpha-1,4-linked glucans, malto-oligosaccharides or glucose. It belongs to the glycoside hydrolase family 13, which represents a large group of (beta/alpha)(8) barrel proteins sharing a similar active site structure. The crystal structures of MTase and its complex with maltose have been determined at 2.4 A and 2.1 A resolution, respectively. MTase is a homodimer, each subunit of which consists of four domains, two of which are structurally homologous to those of other family 13 enzymes. The catalytic core domain has the (beta/alpha)(8) barrel fold with the active-site cleft formed at the C-terminal end of the barrel. Substrate binding experiments have led to the location of two distinct maltose-binding sites; one lies in the active-site cleft, covering subsites -2 and -1; the other is located in a pocket adjacent to the active-site cleft. The structure of MTase, together with the conservation of active-site residues among family 13 glycoside hydrolases, are consistent with a common double-displacement catalytic mechanism for this enzyme. Analysis of maltose binding in the active site reveals that the transfer of dextrinyl residues longer than a maltosyl unit is prevented by termination of the active-site cleft after the -2 subsite by the side-chain of Lys151 and the stretch of residues 314-317, providing an explanation for the strict transfer specificity of MTase.
About this StructureAbout this Structure
1GJW is a Single protein structure of sequence from Thermotoga maritima. Full crystallographic information is available from OCA.
ReferenceReference
The crystal structure of Thermotoga maritima maltosyltransferase and its implications for the molecular basis of the novel transfer specificity., Roujeinikova A, Raasch C, Burke J, Baker PJ, Liebl W, Rice DW, J Mol Biol. 2001 Sep 7;312(1):119-31. PMID:11545590 Page seeded by OCA on Fri May 2 17:40:04 2008