Identification of fungal oxaloacetate hydrolyase within the isocitrate lyase/PEP mutase enzyme superfamily using a sequence marker-based method.
Aspergillus niger produces oxalic acid through the hydrolysis of oxaloacetate, catalyzed by the cytoplasmic enzyme oxaloacetate acetylhydrolase (OAH). The A. niger genome encodes four additional open reading frames with strong sequence similarity to OAH yet only the oahA gene encodes OAH activity. OAH and OAH-like proteins form subclass of the isocitrate lyase/PEP mutase enzyme superfamily, which is ubiquitous present filamentous fungi. Analysis of function-specific residues using a superfamily-based approach revealed an active site serine as a possible sequence marker for OAH activity. We propose that presence of this serine in family members correlates with presence of OAH activity whereas its absence correlates with absence of OAH. This hypothesis was tested by carrying out a serine mutagenesis study with the OAH from the fungal oxalic acid producer Botrytis cinerea and the OAH active plant petal death protein as test systems.
Joosten
Henk-Jan
HJ
Laboratory of Microbiology, Wageningen University, 6703 HA Wageningen, The Netherlands.
Han
Ying
Y
Niu
Weiling
W
Vervoort
Jacques
J
Dunaway-Mariano
Debra
D
Schaap
Peter J
PJ
D015415:Biomarkers / Q000378:metabolism*; D005658:Fungi / Q000145:classification / Q000201:enzymology*; D006867:Hydrolases / Q000378:metabolism*; D007522:Isocitrate Lyase / Q000235:genetics / Q000378:metabolism*; D007700:Kinetics; D013379:Substrate Specificity
D015415:Biomarkers; D006867:Hydrolases; C054172:oxaloacetase; D007522:Isocitrate Lyase