2d06
From Proteopedia
Line 1: | Line 1: | ||
[[Image:2d06.gif|left|200px]] | [[Image:2d06.gif|left|200px]] | ||
- | + | <!-- | |
- | + | The line below this paragraph, containing "STRUCTURE_2d06", 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_2d06| PDB=2d06 | SCENE= }} | |
- | + | ||
- | + | ||
- | }} | + | |
'''Human Sult1A1 Complexed With Pap and estradiol''' | '''Human Sult1A1 Complexed With Pap and estradiol''' | ||
Line 31: | Line 28: | ||
[[Category: McManus, M E.]] | [[Category: McManus, M E.]] | ||
[[Category: Tsvetanov, S.]] | [[Category: Tsvetanov, S.]] | ||
- | [[Category: | + | [[Category: Dead end complex]] |
- | [[Category: | + | [[Category: Estradiol]] |
- | [[Category: | + | [[Category: Pap]] |
- | [[Category: | + | [[Category: Substrarte inhibition]] |
- | [[Category: | + | [[Category: Sult 1a1]] |
- | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 23:27:20 2008'' | |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + |
Revision as of 20:27, 3 May 2008
Human Sult1A1 Complexed With Pap and estradiol
Overview
Human SULT1A1 belongs to the supergene family of sulfotransferases (SULTs) involved in the sulfonation of xeno- and endobiotics. The enzyme is also one of the SULTs responsible for metabolic activation of mutagenic and carcinogenic compounds and therefore is implicated in various cancer forms. Further, it is not well understood how substrate inhibition takes place with rigid fused multiring substrates such as 17beta-estradiol (E2) at high substrate concentrations when subcellular fractions or recombinant enzymes are used. To investigate how estradiol binds to SULT1A1, we co-crystallized SULT1A1 with sulfated estradiol and the cofactor product, PAP (3'-phosphoadenosine 5'-phosphate). The crystal structure of SULT1A1 that we present here has PAP and one molecule of E2 bound in a nonproductive mode in the active site. The structure reveals how the SULT1A1 binding site undergoes conformational changes to accept fused ring substrates such as steroids. In agreement with previous reports, the enzyme shows partial substrate inhibition at high concentrations of E2. A model to explain these kinetics is developed based on the formation of an enzyme x PAP x E2 dead-end complex during catalysis. This model provides a very good quantitative description of the rate versus the [E2] curve. This dead-end complex is proposed to be that described by the observed structure, where E2 is bound in a nonproductive mode.
About this Structure
2D06 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
The structure of human SULT1A1 crystallized with estradiol. An insight into active site plasticity and substrate inhibition with multi-ring substrates., Gamage NU, Tsvetanov S, Duggleby RG, McManus ME, Martin JL, J Biol Chem. 2005 Dec 16;280(50):41482-6. Epub 2005 Oct 12. PMID:16221673 Page seeded by OCA on Sat May 3 23:27:20 2008