Badh2, Encoding Betaine Aldehyde Dehydrogenase, Inhibits the Biosynthesis of 2-Acetyl-1-Pyrroline, a Major Component in Rice Fragrance
- 1 July 2008
- journal article
- Published by Oxford University Press (OUP) in THE PLANT CELL ONLINE
- Vol. 20 (7), 1850-1861
- https://doi.org/10.1105/tpc.108.058917
Abstract
In rice (Oryza sativa), the presence of a dominant Badh2 allele encoding betaine aldehyde dehydrogenase (BADH2) inhibits the synthesis of 2-acetyl-1-pyrroline (2AP), a potent flavor component in rice fragrance. By contrast, its two recessive alleles, badh2-E2 and badh2-E7, induce 2AP formation. Badh2 was found to be transcribed in all tissues tested except for roots, and the transcript was detected at higher abundance in young, healthy leaves than in other tissues. Multiple Badh2 transcript lengths were detected, and the complete, full-length Badh2 transcript was much less abundant than partial Badh2 transcripts. 2AP levels were significantly reduced in cauliflower mosaic virus 35S-driven transgenic lines expressing the complete, but not the partial, Badh2 coding sequences. In accordance, the intact, full-length BADH2 protein (503 residues) appeared exclusively in nonfragrant transgenic lines and rice varieties. These results indicate that the full-length BADH2 protein encoded by Badh2 renders rice nonfragrant by inhibiting 2AP biosynthesis. The BADH2 enzyme was predicted to contain three domains: NAD binding, substrate binding, and oligomerization domains. BADH2 was distributed throughout the cytoplasm, where it is predicted to catalyze the oxidization of betaine aldehyde, 4-aminobutyraldehyde (AB-ald), and 3-aminopropionaldehyde. The presence of null badh2 alleles resulted in AB-ald accumulation and enhanced 2AP biosynthesis. In summary, these data support the hypothesis that BADH2 inhibits 2AP biosynthesis by exhausting AB-ald, a presumed 2AP precursor.Keywords
This publication has 31 references indexed in Scilit:
- The SWISS-MODEL workspace: a web-based environment for protein structure homology modellingBioinformatics, 2005
- Variation of 2-Acetyl-1-Pyrroline Concentration in Aromatic Rice Grains Collected in the Same Region in Japan and Factors Affecting Its ConcentrationPlant Production Science, 2004
- Basmati rice: a reviewInternational Journal of Food Science & Technology, 2002
- A bacterial artificial chromosome (BAC) library ofMalus floribunda821 and contig construction for positional cloning of the apple scab resistance geneVfGenome, 2001
- Rapid Gas Chromatographic Technique for Quantifying 2‐Acetyl‐1‐Pyrroline and Hexanal in Rice (Oryza sativa, L.)Cereal Chemistry Journal, 2000
- Structure of betaine aldehyde dehydrogenase at 2.1 Å resolutionProtein Science, 1998
- Formation of 2-Acetyl-1-pyrroline by Several Bacillus cereus Strains Isolated from Cocoa Fermentation BoxesJournal of Agricultural and Food Chemistry, 1995
- NewAgrobacterium helper plasmids for gene transfer to plantsTransgenic Research, 1993
- Potent odorants of the wheat bread crumb Differences to the crust and effect of a longer dough fermentationZeitschrift für Lebensmittel-Untersuchung und Forschung, 1991
- “Western Blotting”: Electrophoretic transfer of proteins from sodium dodecyl sulfate-polyacrylamide gels to unmodified nitrocellulose and radiographic detection with antibody and radioiodinated protein AAnalytical Biochemistry, 1981