1174218-97-3Relevant academic research and scientific papers
Alternative Pathway to the Formation of trans-Cinnamic Acid Derived from l -Phenylalanine in Tea (Camellia sinensis) Plants and Other Plants
Dong, Fang,Kang, Ming,Liao, Yinyin,Tan, Haibo,Wang, Xiaoqin,Xu, Ping,Yang, Ziyin,Zeng, Lanting
, p. 3415 - 3424 (2020)
trans-Cinnamic acid (CA) is a precursor of many phenylpropanoid compounds, including catechins and aroma compounds, in tea (Camellia sinensis) leaves and is derived from l-phenylalanine (l-Phe) deamination. We have discovered an alternative CA formation pathway from l-Phe via phenylpyruvic acid (PPA) and phenyllactic acid (PAA) in tea leaves through stable isotope-labeled precursor tracing and enzyme reaction evidence. Both PPA reductase genes (CsPPARs) involved in the PPA-to-PAA pathway were isolated from tea leaves and functionally characterized in vitro and in vivo. CsPPAR1 and CsPPAR2 transformed PPA into PAA and were both localized in the leaf cell cytoplasm. Rosa hybrida flowers (economic crop flower), Lycopersicon esculentum Mill. fruits (economic crop fruit), and Arabidopsis thaliana leaves (leaf model plant) also contained this alternative CA formation pathway, suggesting that it occurred in most plants, regardless of different tissues and species. These results improve our understanding of CA biosynthesis in tea plants and other plants.
Stereochemistry and mechanism of a microbial phenylalanine aminomutase
Ratnayake, Nishanka Dilini,Wanninayake, Udayanga,Geiger, James H.,Walker, Kevin D.
supporting information; experimental part, p. 8531 - 8533 (2011/07/29)
The stereochemistry of a phenylalanine aminomutase (PAM) on the andrimid biosynthetic pathway in Pantoea agglomerans (Pa) is reported. PaPAM is a member of the 4-methylidene-1H-imidazol-5(4H)-one (MIO)-dependent family of catalysts and isomerizes (2S)-α-phenylalanine to (3S)-β-phenylalanine, which is the enantiomer of the product made by the mechanistically similar aminomutase TcPAM from Taxus plants. The NH2 and pro-(3S) hydrogen groups at Cα and Cβ, respectively, of the substrate are removed and interchanged completely intramolecularly with inversion of configuration at the migration centers to form β-phenylalanine. This is a contrast to the retention of configuration mechanism followed by TcPAM.
