2d36: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[Image:2d36.gif|left|200px]] | [[Image:2d36.gif|left|200px]] | ||
<!-- | |||
The line below this paragraph, containing "STRUCTURE_2d36", 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_2d36| PDB=2d36 | SCENE= }} | |||
}} | |||
'''The Crystal Structure of Flavin Reductase HpaC''' | '''The Crystal Structure of Flavin Reductase HpaC''' | ||
| Line 31: | Line 28: | ||
[[Category: Okai, M.]] | [[Category: Okai, M.]] | ||
[[Category: Tanokura, M.]] | [[Category: Tanokura, M.]] | ||
[[Category: | [[Category: Flavin reductase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 23:36:58 2008'' | |||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | |||
Revision as of 23:36, 3 May 2008
The Crystal Structure of Flavin Reductase HpaC
OverviewOverview
4-Hydroxyphenylacetate (4-HPA) is oxidized as an energy source by two component enzymes, the large component (HpaB) and the small component (HpaC). HpaB is a 4-HPA monooxygenase that utilizes FADH(2) supplied by a flavin reductase HpaC. We determined the crystal structure of HpaC (ST0723) from the aerobic thermoacidophilic crenarchaeon Sulfolobus tokodaii strain 7 in its three states [NAD(P)(+)-free, NAD(+)-bound, and NADP(+)-bound]. HpaC exists as a homodimer, and each monomer was found to contain an FMN. HpaC preferred FMN to FAD because there was not enough space to accommodate the AMP moiety of FAD in its flavin-binding site. The most striking difference between the NAD(P)(+)-free and the NAD(+)/NADP(+)-bound structures was observed in the N-terminal helix. The N-terminal helices in the NAD(+)/NADP(+)-bound structures rotated ca. 20 degrees relative to the NAD(P)(+)-free structure. The bound NAD(+) has a compact folded conformation with nearly parallel stacking rings of nicotinamide and adenine. The nicotinamide of NAD(+) stacked the isoalloxazine ring of FMN so that NADH could directly transfer hydride. The bound NADP(+) also had a compact conformation but was bound in a reverse direction, which was not suitable for hydride transfer.
About this StructureAbout this Structure
2D36 is a Single protein structure of sequence from Sulfolobus tokodaii str. 7. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of the short-chain flavin reductase HpaC from Sulfolobus tokodaii strain 7 in its three states: NAD(P)(+)(-)free, NAD(+)(-)bound, and NADP(+)(-)bound., Okai M, Kudo N, Lee WC, Kamo M, Nagata K, Tanokura M, Biochemistry. 2006 Apr 25;45(16):5103-10. PMID:16618099 Page seeded by OCA on Sat May 3 23:36:58 2008