The effect of adenosine monophosphate deaminase overexpression on the accumulation of umami-related metabolites in tomatoes.
This study highlights the changes in umami-related nucleotide and glutamate levels when the AMP deaminase gene was elevated in transgenic tomato. Taste is perceived as one of a combination of five sensations, sweet, sour, bitter, salty, and umami. The umami taste is best known as a savoury sensation and plays a central role in food flavour, palatability, and eating satisfaction. Umami flavour can be imparted by the presence of glutamate and is greatly enhanced by the addition of ribonucleotides, such as inosine monophosphate (IMP) and guanosine monophosphate (GMP). The production of IMP is regulated by the enzyme adenosine monophosphate (AMP) deaminase which functions to convert AMP into IMP. We have generated transgenic tomato (Solanum lycopersicum) lines over expressing AMP deaminase under the control of a fruit-specific promoter. The transgenic lines showed substantially enhanced levels of AMP deaminase expression in comparison to the wild-type control. Elevated AMP deaminase levels resulted in the reduced accumulation of glutamate and increased levels of the umami nucleotide GMP. AMP concentrations were unchanged. The effects on the levels of glutamate and GMP were unexpected and are discussed in relation to the metabolite flux within this pathway.
School of Biological Sciences, Universiti Sains Malaysia, 11800, Penang, Malaysia.|Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
Bee Lynn
BL
Chew
Division of Food Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
Ian D
ID
Fisk
Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
Rupert
R
Fray
Division of Nutritional Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
Gregory A
GA
Tucker
Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
Zsuzsanna
Z
Bodi
Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
Alison
A
Ferguson
Division of Nutritional Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK.
Wei
W
Xia
Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, Leicestershire, LE12 5RD, UK. Graham.Seymour@nottingham.ac.uk.
Graham B
GB
Seymour
D000659:AMP Deaminase / Q000378:metabolism*; D000249:Adenosine Monophosphate / Q000378:metabolism; D005638:Fruit / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D018698:Glutamic Acid / Q000378:metabolism; D006157:Guanosine Monophosphate / Q000378:metabolism; D018551:Solanum lycopersicum / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D055442:Metabolome / Q000235:genetics; D010940:Plant Proteins; D030821:Plants, Genetically Modified; D060888:Real-Time Polymerase Chain Reaction; D013649:Taste; D019076:Transgenes
D010940:Plant Proteins; D018698:Glutamic Acid; D000249:Adenosine Monophosphate; D006157:Guanosine Monophosphate; D000659:AMP Deaminase
Glutamate; Inosine monophosphate and guanosine monophosphate; Transgenic tomato; Umami
Biomed Res Int. 2015;2015:189402
26247011
Plant Cell. 2012 Nov;24(11):4437-51
23136376
Physiol Behav. 1991 May;49(5):833-41
1679557
Amino Acids. 2010 May;38(5):1523-32
19876714
Plant J. 2005 Jun;42(5):743-56
15918887
Plant Cell Physiol. 2008 Sep;49(9):1378-89
18713763
J Exp Bot. 2015 Jun;66(11):3381-9
25878356
Plant Physiol. 1997 May;114(1):119-29
9159944
Plant Physiol. 2009 Dec;151(4):1729-40
19812183
J Nutr. 2000 Apr;130(4S Suppl):921S-6S
10736353
Nature. 2012 May 30;485(7400):635-41
22660326
Annu Rev Plant Biol. 2006;57:805-36
16669783
Trends Plant Sci. 2004 Mar;9(3):110-5
15003233
Plant Cell Physiol. 2006 Mar;47(3):426-31
16381658
Plant Physiol. 2007 Apr;143(4):1752-60
17307896