Isolation of a new dual-functional caffeine synthase gene encoding an enzyme for the conversion of 7-methylxanthine to caffeine from coffee (Coffea arabica L.).
In coffee and tea plants, caffeine is synthesized from xanthosine via a pathway that includes three methylation steps. We report the isolation of a bifunctional coffee caffeine synthase (CCS1) clone from coffee endosperm by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) technique using previously reported sequence information for theobromine synthases (CTSs). The predicted amino acid sequences of CCS1 are more than 80% identical to CTSs and are about 40% similar to those of tea caffeine synthase (TCS1). Interestingly, CCS1 has dual methylation activity like tea TCS1.
Mizuno
Kouichi
K
Institute of Agricultural and Forest Engineering, University of Tsukuba, Tsukuba Science City, Ibaraki 305-8572, Japan. koumno@akita-pu.ac.jp
Okuda
Akira
A
Kato
Misako
M
Yoneyama
Naho
N
Tanaka
Hiromi
H
Ashihara
Hiroshi
H
Fujimura
Tatsuhito
T
D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D040503:Coffea / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D008745:Methylation; D008780:Methyltransferases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013805:Theobromine / Q000378:metabolism; D014970:Xanthines / Q000378:metabolism*
D018076:DNA, Complementary; D011994:Recombinant Proteins; D014970:Xanthines; C064273:7-methylxanthine; D008780:Methyltransferases; C120479:caffeine synthase; D013805:Theobromine