title: Insight into Coenzyme A cofactor binding and the mechanism of acyl-transfer in an acylating aldehyde dehydrogenase from Clostridium phytofermentans.
abstract: The breakdown of fucose and rhamnose released from plant cell walls by the cellulolytic soil bacterium Clostridium phytofermentans produces toxic aldehyde intermediates. To enable growth on these carbon sources, the pathway for the breakdown of fucose and rhamnose is encapsulated within a bacterial microcompartment (BMC). These proteinaceous organelles sequester the toxic aldehyde intermediates and allow the efficient action of acylating aldehyde dehydrogenase enzymes to produce an acyl-CoA that is ultimately used in substrate-level phosphorylation to produce ATP. Here we analyse the kinetics of the aldehyde dehydrogenase enzyme from the fucose/rhamnose utilisation BMC with different short-chain fatty aldehydes and show that it has activity against substrates with up to six carbon atoms, with optimal activity against propionaldehyde. We have also determined the X-ray crystal structure of this enzyme in complex with CoA and show that the adenine nucleotide of this cofactor is bound in a distinct pocket to the same group in NAD(+). This work is the first report of the structure of CoA bound to an aldehyde dehydrogenase enzyme and our crystallographic model provides important insight into the differences within the active site that distinguish the acylating from non-acylating aldehyde dehydrogenase enzymes.
authors.affiliation: Institute of Quantitative Biology, Biochemistry and Biotechnology, The University of Edinburgh, Max Born Crescent, EH9 3BF, UK.
authors.forename: Laura R
authors.initials: LR
authors.lastname: Tuck
authors.affiliation: Institute of Quantitative Biology, Biochemistry and Biotechnology, The University of Edinburgh, Max Born Crescent, EH9 3BF, UK.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Altenbach
authors.affiliation: Institute of Quantitative Biology, Biochemistry and Biotechnology, The University of Edinburgh, Max Born Crescent, EH9 3BF, UK.
authors.forename: Thiau Fu
authors.initials: TF
authors.lastname: Ang
authors.affiliation: Institute for Cell and Molecular Biosciences, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Crawshaw
authors.affiliation: EaStChem, School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh, UK, EH9 3FJ, UK.
authors.forename: Dominic J
authors.initials: DJ
authors.lastname: Campopiano
authors.affiliation: EaStChem, School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh, UK, EH9 3FJ, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Clarke
authors.affiliation: Institute of Quantitative Biology, Biochemistry and Biotechnology, The University of Edinburgh, Max Born Crescent, EH9 3BF, UK.
authors.forename: Jon
authors.initials: J
authors.lastname: Marles-Wright
mesh_terms: D000215:Acylation; D000444:Aldehyde Dehydrogenase / Q000737:chemistry*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D020134:Catalytic Domain; D016360:Clostridioides difficile / Q000201:enzymology*; D003065:Coenzyme A / Q000737:chemistry*; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008958:Models, Molecular; D009243:NAD / Q000737:chemistry; D011485:Protein Binding; D000072756:Protein Conformation, alpha-Helical; D054730:Protein Interaction Domains and Motifs
chemical_list: D001426:Bacterial Proteins; D009243:NAD; D000444:Aldehyde Dehydrogenase; D003065:Coenzyme A