From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
| Line 1: |
Line 1: |
| - | [[Image:1c2y.gif|left|200px]] | + | {{Seed}} |
| | + | [[Image:1c2y.png|left|200px]] |
| | | | |
| | <!-- | | <!-- |
| Line 9: |
Line 10: |
| | {{STRUCTURE_1c2y| PDB=1c2y | SCENE= }} | | {{STRUCTURE_1c2y| PDB=1c2y | SCENE= }} |
| | | | |
| - | '''CRYSTAL STRUCTURES OF A PENTAMERIC FUNGAL AND AN ICOSAHEDRAL PLANT LUMAZINE SYNTHASE REVEALS THE STRUCTURAL BASIS FOR DIFFERENCES IN ASSEMBLY'''
| + | ===CRYSTAL STRUCTURES OF A PENTAMERIC FUNGAL AND AN ICOSAHEDRAL PLANT LUMAZINE SYNTHASE REVEALS THE STRUCTURAL BASIS FOR DIFFERENCES IN ASSEMBLY=== |
| | | | |
| | | | |
| - | ==Overview==
| + | <!-- |
| - | Lumazine synthase catalyzes the penultimate step in the synthesis of riboflavin in plants, fungi, and microorganisms. The enzyme displays two quaternary structures, the pentameric forms in yeast and fungi and the 60-meric icosahedral capsids in plants and bacteria. To elucidate the structural features that might be responsible for differences in assembly, we have determined the crystal structures of lumazine synthase, complexed with the inhibitor 5-nitroso-6-ribitylamino-2,4-pyrimidinedione, from spinach and the fungus Magnaporthe grisea to 3.3 and 3.1 A resolution, respectively. The overall structure of the subunit and the mode of inhibitor binding are very similar in these enzyme species. The core of the subunit consists of a four-stranded parallel beta-sheet sandwiched between two helices on one side and three helices on the other. The packing of the five subunits in the pentameric M. grisea lumazine synthase is very similar to the packing in the pentameric substructures in the icosahedral capsid of the plant enzyme. Two structural features can be correlated to the differences in assembly. In the plant enzyme, the N-terminal beta-strand interacts with the beta-sheet of the adjacent subunit, thus extending the sheet from four to five strands. In fungal lumazine synthase, an insertion of two residues after strand beta1 results in a completely different orientation of this part of the polypeptide chain and this conformational difference prevents proper packing of the subunits at the trimer interface in the icosahedron. In the spinach enzyme, the beta-hairpin connecting helices alpha4 and alpha5 participates in the packing at the trimer interface of the icosahedron. Another insertion of two residues at this position of the polypeptide chain in the fungal enzyme disrupts the hydrogen bonding in the hairpin, and the resulting change in conformation of this loop also interferes with proper intrasubunit contacts at the trimer interface.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_10595538}}, adds the Publication Abstract to the page |
| | + | (as it appears on PubMed at http://www.pubmed.gov), where 10595538 is the PubMed ID number. |
| | + | --> |
| | + | {{ABSTRACT_PUBMED_10595538}} |
| | | | |
| | ==About this Structure== | | ==About this Structure== |
| Line 29: |
Line 33: |
| | [[Category: Viitanen, P V.]] | | [[Category: Viitanen, P V.]] |
| | [[Category: Riboflavin biosynthesis]] | | [[Category: Riboflavin biosynthesis]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 12:16:04 2008'' | + | |
| | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jun 30 20:08:19 2008'' |
Revision as of 17:08, 30 June 2008
Template:STRUCTURE 1c2y
CRYSTAL STRUCTURES OF A PENTAMERIC FUNGAL AND AN ICOSAHEDRAL PLANT LUMAZINE SYNTHASE REVEALS THE STRUCTURAL BASIS FOR DIFFERENCES IN ASSEMBLY
Template:ABSTRACT PUBMED 10595538
About this Structure
1C2Y is a Single protein structure of sequence from Spinacia oleracea. Full crystallographic information is available from OCA.
Reference
Crystal structure analysis of a pentameric fungal and an icosahedral plant lumazine synthase reveals the structural basis for differences in assembly., Persson K, Schneider G, Jordan DB, Viitanen PV, Sandalova T, Protein Sci. 1999 Nov;8(11):2355-65. PMID:10595538
Page seeded by OCA on Mon Jun 30 20:08:19 2008
