PDBsum entry: 1eav

Molybdenum cofactor biosynthesis

PDB id: 1eav

Contents

Protein chains

(+ 2 more) 160 a.a. *

Waters ×51

* Residue conservation analysis

PDB id:

1eav

Name:

Molybdenum cofactor biosynthesis

Title:

Crystal structures of human gephyrin and plant cnx1 g domains - comparative analysis and functional implications

Structure:

Molybdopterin biosynthesis cnx1 protein. Chain: a, b, c, d, e, f, g, h. Fragment: cnx1 g-domain residues 462-623. Synonym: cnx1g, molybdenum cofactor biosynthesis enzyme. Engineered: yes

Source:

Arabidopsis thaliana. Mouse-ear cress. Organism_taxid: 3702. Strain: cv. Columbia. Expressed in: escherichia coli. Expression_system_taxid: 562. Expression_system_cell_line: dl41.

Biol. unit:

Trimer (from PDB file)

Resolution:

2.6Å R-factor: 0.223 R-free: 0.251

Authors:

G.Schwarz,N.Schrader,R.R.Mendel,H.J.Hecht

Key ref:

G.Schwarz et al. (2001). Crystal structures of human gephyrin and plant Cnx1 G domains: comparative analysis and functional implications. J Mol Biol, 312, 405-418. PubMed id: 11554796 DOI: 10.1006/jmbi.2001.4952

Date:

17-Jul-01 Release date: 23-Nov-01

Protein chains

Q39054  (CNX1_ARATH) -  Molybdopterin biosynthesis protein CNX1

Seq: 670 a.a.

Struc: 160 a.a.

Enzyme reactions

• Enzyme class 2: E.C.2.10.1.1 - Molybdopterin molybdotransferase.
• Reaction: Adenylyl-molybdopterin + molybdate = molybdenum cofactor + AMP
• Cofactor: Zinc or magnesium
• Enzyme class 3: E.C.2.7.7.75 - Molybdopterin adenylyltransferase.
• Reaction: ATP + molybdopterin = diphosphate + adenylyl-molybdopterin
• Cofactor: Manganese or magnesium

Note, where more than one E.C. class is given (as above), each may correspond to a different protein domain or, in the case of polyprotein precursors, to a different mature protein.

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

 Gene Ontology (GO) functional annotation 

• Biological process: Mo-molybdopterin cofactor biosynthetic process (1 term)

reference

DOI no: 10.1006/jmbi.2001.4952

J Mol Biol 312:405-418 (2001)

PubMed id: 11554796

Crystal structures of human gephyrin and plant Cnx1 G domains: comparative analysis and functional implications.

G.Schwarz, N.Schrader, R.R.Mendel, H.J.Hecht, H.Schindelin.

ABSTRACT

The molybdenum cofactor (Moco) consists of a unique and conserved pterin derivative, usually referred to as molybdopterin (MPT), which coordinates the essential transition metal molybdenum (Mo). Moco is required for the enzymatic activities of all Mo-enzymes, with the exception of nitrogenase and is synthesized by an evolutionary old multi-step pathway that is dependent on the activities of at least six gene products. In eukaryotes, the final step of Moco biosynthesis, i.e. transfer and insertion of Mo into MPT, is catalyzed by the two-domain proteins Cnx1 in plants and gephyrin in mammals. Gephyrin is ubiquitously expressed, and was initially found in the central nervous system, where it is essential for clustering of inhibitory neuroreceptors in the postsynaptic membrane. Gephyrin and Cnx1 contain at least two functional domains (E and G) that are homologous to the Escherichia coli proteins MoeA and MogA, the atomic structures of which have been solved recently. Here, we present the crystal structures of the N-terminal human gephyrin G domain (Geph-G) and the C-terminal Arabidopsis thaliana Cnx1 G domain (Cnx1-G) at 1.7 and 2.6 A resolution, respectively. These structures are highly similar and compared to MogA reveal four major differences in their three-dimensional structures: (1) In Geph-G and Cnx1-G an additional alpha-helix is present between the first beta-strand and alpha-helix of MogA. (2) The loop between alpha 2 and beta 2 undergoes conformational changes in all three structures. (3) A beta-hairpin loop found in MogA is absent from Geph-G and Cnx1-G. (4) The C terminus of Geph-G follows a different path from that in MogA. Based on the structures of the eukaryotic proteins and their comparisons with E. coli MogA, the predicted binding site for MPT has been further refined. In addition, the characterized alternative splice variants of gephyrin are analyzed in the context of the three-dimensional structure of Geph-G.

Selected figure(s)

Figure 4.
Figure 4. Structural comparisons of the Geph-G and MogA trimers. Stereo view of a least-squares superposition of the Geph-G (red) and MogA (yellow) trimers. Shown is the central region around the 3-fold axis including the trimerization helix a5. The conserved prolines at the end of the helix and two side-chains forming either a hydrophobic (Geph-G) or hydrophilic core (MogA) of the trimers are highlighted.

Figure 6.
Figure 6. Comparisons of the hydrophobic surface properties of (a) Geph-G, (b) Cnx1-G and (c) MogA trimers. The view is along the 3-fold axis onto the same side of each trimer shown for Geph-G in Figure 3. Hydrophobic residues are colored in green.

The above figures are reprinted by permission from Elsevier: J Mol Biol (2001, 312, 405-418) copyright 2001.

Figures were selected by an automated process.