The decarboxylation of the weak-acid preservative, sorbic acid, is encoded by linked genes in Aspergillus spp.
The ability to resist anti-microbial compounds is of key evolutionary benefit to microorganisms. Aspergillus niger has previously been shown to require the activity of a phenylacrylic acid decarboxylase (encoded by padA1) for the decarboxylation of the weak-acid preservative sorbic acid (2,4-hexadienoic acid) to 1,3-pentadiene. It is now shown that this decarboxylation process also requires the activity of a putative 4-hydroxybenzoic acid (3-octaprenyl-4-hydroxybenzoic acid) decarboxylase, encoded by a gene termed ohbA1, and a putative transcription factor, sorbic acid decarboxylase regulator, encoded by sdrA. The padA1,ohbA1 and sdrA genes are in close proximity to each other on chromosome 6 in the A. niger genome and further bioinformatic analysis revealed conserved synteny at this locus in several Aspergillus species and other ascomycete fungi indicating clustering of metabolic function. This cluster is absent from the genomes of A. fumigatus and A. clavatus and, as a consequence, neither species is capable of decarboxylating sorbic acid.
Plumridge
Andrew
A
School of Biology, University Park, University of Nottingham, Nottingham NG7 2RD, UK.
Melin
Petter
P
Stratford
Malcolm
M
Novodvorska
Michaela
M
Shunburne
Lee
L
Dyer
Paul S
PS
Roubos
Johannes A
JA
Menke
Hildegard
H
Stark
Jacques
J
Stam
Hein
H
Archer
David B
DB
D000466:Alkadienes / Q000378:metabolism; D000595:Amino Acid Sequence; D000935:Antifungal Agents / Q000378:metabolism*; D001234:Aspergillus niger / Q000378:metabolism*; D002262:Carboxy-Lyases / Q000235:genetics; D003653:Decarboxylation; D005656:Fungal Proteins / Q000235:genetics; D023061:Gene Order; D005800:Genes, Fungal; D053858:Metabolic Networks and Pathways / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D005810:Multigene Family; D010226:Parabens / Q000378:metabolism; D010420:Pentanes / Q000378:metabolism; D016415:Sequence Alignment; D013011:Sorbic Acid / Q000378:metabolism*; D026801:Synteny; D014157:Transcription Factors / Q000235:genetics
D000466:Alkadienes; D000935:Antifungal Agents; D005656:Fungal Proteins; D010226:Parabens; D010420:Pentanes; D014157:Transcription Factors; D002262:Carboxy-Lyases; C011970:1,3-pentadiene; C038193:4-hydroxybenzoic acid; D013011:Sorbic Acid