2e0k

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:2e0k.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:2e0k.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_2e0k| PDB=2e0k | SCENE= }}
{{STRUCTURE_2e0k| PDB=2e0k | SCENE= }}
-
'''Crystal structure of CbiL, a methyltransferase involved in anaerobic vitamin B12 biosynthesis'''
+
===Crystal structure of CbiL, a methyltransferase involved in anaerobic vitamin B12 biosynthesis===
-
==Overview==
+
<!--
-
During anaerobic cobalamin (vitamin B12) biosynthesis, CbiL catalyzes methylation at the C-20 position of a cyclic tetrapyrrole ring using S-adenosylmethionine as a methyl group source. This methylation is a key modification for the ring contraction process, by which a porphyrin-type tetrapyrrole ring is converted to a corrin ring through elimination of the modified C-20 and direct bonding of C-1 to C-19. We have determined the crystal structures of Chlorobium tepidum CbiL and CbiL in complex with S-adenosylhomocysteine (the S-demethyl form of S-adenosylmethionine). CbiL forms a dimer in the crystal, and each subunit consists of N-terminal and C-terminal domains. S-Adenosylhomocysteine binds to a cleft between the two domains, where it is specifically recognized by extensive hydrogen bonding and van der Waals interactions. The orientation of the cobalt-factor II substrate was modeled by simulation, and the predicted model suggests that the hydroxy group of Tyr226 is located in close proximity to the C-20 atom as well as the C-1 and C-19 atoms of the tetrapyrrole ring. These configurations allow us to propose a catalytic mechanism: the conserved Tyr226 residue in CbiL catalyzes the direct transfer of a methyl group from S-adenosylmethionine to the substrate through an S(N)2-like mechanism. Furthermore, the structural model of CbiL binding to its substrate suggests the axial residue coordinated to the central cobalt of cobalt-factor II.
+
The line below this paragraph, {{ABSTRACT_PUBMED_17229157}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 17229157 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_17229157}}
==About this Structure==
==About this Structure==
Line 28: Line 32:
[[Category: S-adenosylmethionine]]
[[Category: S-adenosylmethionine]]
[[Category: Tetrapyrrole]]
[[Category: Tetrapyrrole]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 01:42:39 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 15:04:02 2008''

Revision as of 12:04, 28 July 2008

Image:2e0k.png

Template:STRUCTURE 2e0k

Crystal structure of CbiL, a methyltransferase involved in anaerobic vitamin B12 biosynthesis

Template:ABSTRACT PUBMED 17229157

About this Structure

2E0K is a Single protein structure of sequence from Chlorobaculum tepidum. Full crystallographic information is available from OCA.

Reference

Crystal structures of CbiL, a methyltransferase involved in anaerobic vitamin B biosynthesis, and CbiL in complex with S-adenosylhomocysteine--implications for the reaction mechanism., Wada K, Harada J, Yaeda Y, Tamiaki H, Oh-Oka H, Fukuyama K, FEBS J. 2007 Jan;274(2):563-73. PMID:17229157

Page seeded by OCA on Mon Jul 28 15:04:02 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2e0k"
Personal tools