5DBV: Structure of a C269A mutant of propionaldehyde dehydrogenase from the Clostridium phytofermentans fucose utilisation bacterial microcompartment

Citation:
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.
PDB ID: 5DBVDownload
MMDB ID: 137475
PDB Deposition Date: 2015/8/22
Updated in MMDB: 2017/09
Experimental Method:
x-ray diffraction
Resolution: 1.77  Å
Source Organism:
Similar Structures:
Biological Unit for 5DBV: tetrameric; determined by author and by software (PISA)
Molecular Components in 5DBV
Label Count Molecule
Proteins (4 molecules)
4
Aldehyde Dehydrogenase
Molecule annotation
Chemicals (32 molecules)
1
12
2
4
3
16
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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