PDBsum entry 1m7y

Lyase

PDB id: 1m7y

Contents

Protein chain

424 a.a. *

Ligands

PPG

MRD

Waters ×332

* Residue conservation analysis

PDB id:

1m7y

Name:

Lyase

Title:

Crystal structure of apple acc synthase in complex with l- aminoethoxyvinylglycine

Structure:

1-aminocyclopropane-1-carboxylate synthase. Chain: a. Fragment: residues 1-435. Synonym: acc synthase. Engineered: yes

Source:

Malus x domestica. Organism_taxid: 3750. Tissue: fruit cortical. Expressed in: escherichia coli. Expression_system_taxid: 562.

Biol. unit:

Dimer (from PDB file)

Resolution:

1.60Å R-factor: 0.205 R-free: 0.219

Authors:

G.Capitani,D.Mccarthy,H.Gut,M.G.Gruetter,J.F.Kirsch

Key ref:

G.Capitani et al. (2002). Apple 1-aminocyclopropane-1-carboxylate synthase in complex with the inhibitor L-aminoethoxyvinylglycine. Evidence for a ketimine intermediate. J Biol Chem, 277, 49735-49742. PubMed id: 12228256 DOI: 10.1074/jbc.M208427200

Date:

23-Jul-02 Release date: 23-Dec-02

Protein chain

P37821  (1A1C_MALDO) -  1-aminocyclopropane-1-carboxylate synthase from Malus domestica

Seq: 473 a.a.

Struc: 424 a.a.

Enzyme reactions

• Enzyme class: E.C.4.4.1.14 - 1-aminocyclopropane-1-carboxylate synthase.
• Pathway: Ethylene Biosynthesis
• Reaction: S-adenosyl-L-methionine = 1-aminocyclopropane-1-carboxylate + S-methyl- 5'-thioadenosine + H⁺

S-adenosyl-L-methionine = 1-aminocyclopropane-1-carboxylate (Bound ligand (Het Group name = MRD) matches with 50.00% similarity) + S-methyl- 5'-thioadenosine + H(+)

• Cofactor: Pyridoxal 5'-phosphate

Pyridoxal 5'-phosphate (Bound ligand (Het Group name = PPG) matches with 55.56% similarity)

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

reference

DOI no: 10.1074/jbc.M208427200

J Biol Chem 277:49735-49742 (2002)

PubMed id: 12228256

Apple 1-aminocyclopropane-1-carboxylate synthase in complex with the inhibitor L-aminoethoxyvinylglycine. Evidence for a ketimine intermediate.

G.Capitani, D.L.McCarthy, H.Gut, M.G.Grütter, J.F.Kirsch.

ABSTRACT

The 1.6-A crystal structure of the covalent ketimine complex of apple 1-aminocyclopropane-1-carboxylate (ACC) synthase with the potent inhibitor l-aminoethoxyvinylglycine (AVG) is described. ACC synthase catalyzes the committed step in the biosynthesis of ethylene, a plant hormone that is responsible for the initiation of fruit ripening and for regulating many other developmental processes. AVG is widely used in plant physiology studies to inhibit the activity of ACC synthase. The structural assignment is supported by the fact that the complex absorbs maximally at 341 nm. These results are not in accord with the recently reported crystal structure of the tomato ACC synthase AVG complex, which claims that the inhibitor only associates noncovalently. The rate constant for the association of AVG with apple ACC synthase was determined by stopped-flow spectrophotometry (2.1 x 10(5) m(-1) s(-1)) and by the rate of loss of enzyme activity (1.1 x 10(5) m(-1) s(-1)). The dissociation rate constant determined by activity recovery is 2.4 x 10(-6) s(-1). Thus, the calculated K(d) value is 10-20 pm.

Selected figure(s)

Figure 6.
Fig. 6. A, superposition of the active sites of unliganded (sea green) and AVG-bound (yellow) ACC synthase. Only selected residues are shown. B, the active sites of AVG-bound ACC synthase (gray) and cystathionine -lyase (sea green). C, the C traces of unliganded (yellow) and AVG-bound (blue) ACC synthase. This illustration was prepared with DINO.

Figure 7.
Fig. 7. LIGPLOT (13) representation of the hydrogen bonding between ACC synthase and the AVG·PLP adduct.

The above figures are reprinted by permission from the ASBMB: J Biol Chem (2002, 277, 49735-49742) copyright 2002.

Figures were selected by an automated process.