1sfr: Difference between revisions
New page: left|200px<br /><applet load="1sfr" size="450" color="white" frame="true" align="right" spinBox="true" caption="1sfr, resolution 2.70Å" /> '''Crystal Structure of... |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:1sfr.gif|left|200px]]<br /><applet load="1sfr" size=" | [[Image:1sfr.gif|left|200px]]<br /><applet load="1sfr" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1sfr, resolution 2.70Å" /> | caption="1sfr, resolution 2.70Å" /> | ||
'''Crystal Structure of the Mycobacterium tuberculosis Antigen 85A Protein'''<br /> | '''Crystal Structure of the Mycobacterium tuberculosis Antigen 85A Protein'''<br /> | ||
==Overview== | ==Overview== | ||
The maintenance of the highly hydrophobic cell wall is central to the | The maintenance of the highly hydrophobic cell wall is central to the survival of Mycobacterium tuberculosis within its host environment. The antigen 85 proteins (85A, 85B, and 85C) of M. tuberculosis help maintain the integrity of the cell wall 1) by catalyzing the transfer of mycolic acids to the cell wall arabinogalactan and 2) through the synthesis of trehalose dimycolate (cord factor). Additionally, these secreted proteins allow for rapid invasion of alveolar macrophages via direct interactions between the host immune system and the invading bacillus. Here we describe two crystal structures: the structure of antigen 85C co-crystallized with octylthioglucoside as substrate, resolved to 2.0 A, and the crystal structure of antigen 85A, which was solved at a resolution of 2.7 A. The structure of 85C with the substrate analog identifies residues directly involved in substrate binding. Elucidation of the antigen 85A structure, the last of the three antigen 85 homologs to be solved, shows that the active sites of the three antigen 85 proteins are virtually identical, indicating that these share the same substrate. However, in contrast to the high level of conservation within the substrate-binding site and the active site, surface residues disparate from the active site are quite variable, indicating that three antigen 85 enzymes are needed to evade the host immune system. | ||
==About this Structure== | ==About this Structure== | ||
1SFR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http:// | 1SFR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SFR OCA]. | ||
==Reference== | ==Reference== | ||
| Line 13: | Line 13: | ||
[[Category: Mycobacterium tuberculosis]] | [[Category: Mycobacterium tuberculosis]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Belisle, J | [[Category: Belisle, J T.]] | ||
[[Category: Besra, G | [[Category: Besra, G S.]] | ||
[[Category: Ronning, D | [[Category: Ronning, D R.]] | ||
[[Category: Sacchettini, J | [[Category: Sacchettini, J C.]] | ||
[[Category: TBSGC, TB | [[Category: TBSGC, TB Structural Genomics Consortium.]] | ||
[[Category: Vissa, V.]] | [[Category: Vissa, V.]] | ||
[[Category: alpha/beta hydrolase]] | [[Category: alpha/beta hydrolase]] | ||
| Line 26: | Line 26: | ||
[[Category: tbsgc]] | [[Category: tbsgc]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:01:02 2008'' | ||
Revision as of 16:01, 21 February 2008
|
Crystal Structure of the Mycobacterium tuberculosis Antigen 85A Protein
OverviewOverview
The maintenance of the highly hydrophobic cell wall is central to the survival of Mycobacterium tuberculosis within its host environment. The antigen 85 proteins (85A, 85B, and 85C) of M. tuberculosis help maintain the integrity of the cell wall 1) by catalyzing the transfer of mycolic acids to the cell wall arabinogalactan and 2) through the synthesis of trehalose dimycolate (cord factor). Additionally, these secreted proteins allow for rapid invasion of alveolar macrophages via direct interactions between the host immune system and the invading bacillus. Here we describe two crystal structures: the structure of antigen 85C co-crystallized with octylthioglucoside as substrate, resolved to 2.0 A, and the crystal structure of antigen 85A, which was solved at a resolution of 2.7 A. The structure of 85C with the substrate analog identifies residues directly involved in substrate binding. Elucidation of the antigen 85A structure, the last of the three antigen 85 homologs to be solved, shows that the active sites of the three antigen 85 proteins are virtually identical, indicating that these share the same substrate. However, in contrast to the high level of conservation within the substrate-binding site and the active site, surface residues disparate from the active site are quite variable, indicating that three antigen 85 enzymes are needed to evade the host immune system.
About this StructureAbout this Structure
1SFR is a Single protein structure of sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA.
ReferenceReference
Mycobacterium tuberculosis antigen 85A and 85C structures confirm binding orientation and conserved substrate specificity., Ronning DR, Vissa V, Besra GS, Belisle JT, Sacchettini JC, J Biol Chem. 2004 Aug 27;279(35):36771-7. Epub 2004 Jun 10. PMID:15192106
Page seeded by OCA on Thu Feb 21 15:01:02 2008