Involvement of snapdragon benzaldehyde dehydrogenase in benzoic acid biosynthesis.
Benzoic acid (BA) is an important building block in a wide spectrum of compounds varying from primary metabolites to secondary products. Benzoic acid biosynthesis from L-phenylalanine requires shortening of the propyl side chain by two carbons, which can occur via a beta-oxidative pathway or a non-beta-oxidative pathway, with benzaldehyde as a key intermediate. The non-beta-oxidative route requires benzaldehyde dehydrogenase (BALDH) to convert benzaldehyde to BA. Using a functional genomic approach, we identified an Antirrhinum majus (snapdragon) BALDH, which exhibits 40% identity to bacterial BALDH. Transcript profiling, biochemical characterization of the purified recombinant protein, molecular homology modeling, in vivo stable isotope labeling, and transient expression in petunia flowers reveal that BALDH is capable of oxidizing benzaldehyde to BA in vivo. GFP localization and immunogold labeling studies show that this biochemical step occurs in the mitochondria, raising a question about the role of subcellular compartmentalization in BA biosynthesis.
Long
Michael C
MC
Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907, USA.
Nagegowda
Dinesh A
DA
Kaminaga
Yasuhisa
Y
Ho
Kwok Ki
KK
Kish
Christine M
CM
Schnepp
Jennifer
J
Sherman
Debra
D
Weiner
Henry
H
Rhodes
David
D
Dudareva
Natalia
N
D032161:Antirrhinum / Q000201:enzymology* / Q000235:genetics; D050727:Benzaldehyde Dehydrogenase (NADP+) / Q000235:genetics / Q000378:metabolism*; D019817:Benzoic Acid / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D008928:Mitochondria / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D032306:Petunia / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
D018076:DNA, Complementary; D010940:Plant Proteins; D018749:RNA, Plant; D011994:Recombinant Proteins; D019817:Benzoic Acid; D050727:Benzaldehyde Dehydrogenase (NADP+)