Abstract
Malyl-CoA lyase (MCL) is an Mg2+-dependent enzyme that catalyzes the reversible cleavage of (2S)-4-malyl-CoA to yield acetyl-CoA and glyoxylate. MCL enzymes, which are found in a variety of bacteria, are members of the citrate lyase-like family and are involved in the assimilation of one- and two-carbon compounds. Here, the 1.56 Å resolution X-ray crystal structure of MCL from Methylobacterium extorquens AM1 with bound Mg2+ is presented. Structural alignment with the closely related Rhodobacter sphaeroides malyl-CoA lyase complexed with Mg2+, oxalate and CoA allows a detailed analysis of the domain motion of the enzyme caused by substrate binding. Alignment of the structures shows that a simple hinge motion centered on the conserved residues Phe268 and Thr269 moves the C-terminal domain by about 30° relative to the rest of the molecule. This domain motion positions a conserved aspartate residue located in the C-terminal domain in the active site of the adjacent monomer, which may serve as a general acid/base in the catalytic mechanism.
Keywords:
Methylobacterium extorquens; biofuels; malyl-CoA lyase; metabolic engineering; methanol.
MeSH terms
-
Acyl Coenzyme A / chemistry*
-
Acyl Coenzyme A / metabolism
-
Amino Acid Sequence
-
Bacterial Proteins / chemistry*
-
Bacterial Proteins / genetics
-
Bacterial Proteins / metabolism
-
Catalytic Domain
-
Cations, Divalent
-
Cloning, Molecular
-
Coenzyme A / chemistry
-
Coenzyme A / metabolism
-
Crystallography, X-Ray
-
Escherichia coli / genetics
-
Escherichia coli / metabolism
-
Gene Expression
-
Magnesium / chemistry*
-
Magnesium / metabolism
-
Methylobacterium extorquens / chemistry*
-
Methylobacterium extorquens / enzymology
-
Models, Molecular
-
Oxalic Acid / chemistry
-
Oxalic Acid / metabolism
-
Oxo-Acid-Lyases / chemistry*
-
Oxo-Acid-Lyases / genetics
-
Oxo-Acid-Lyases / metabolism
-
Plasmids / chemistry
-
Plasmids / metabolism
-
Protein Binding
-
Protein Conformation, alpha-Helical
-
Protein Conformation, beta-Strand
-
Protein Interaction Domains and Motifs
-
Protein Structure, Quaternary
-
Recombinant Proteins / chemistry
-
Recombinant Proteins / genetics
-
Recombinant Proteins / metabolism
-
Rhodobacter sphaeroides / chemistry
-
Rhodobacter sphaeroides / enzymology
-
Substrate Specificity
Substances
-
Acyl Coenzyme A
-
Bacterial Proteins
-
Cations, Divalent
-
Recombinant Proteins
-
malyl-coenzyme A
-
Oxalic Acid
-
Oxo-Acid-Lyases
-
malyl-CoA lyase
-
Magnesium
-
Coenzyme A