Publications

• Purification, cloning and functional expression of hydroxyphenylpyruvate reductase involved in rosmarinic acid biosynthesis in cell cultures of Coleus blumei.

  Kim K.H., Janiak V., Petersen M.

  Hydroxyphenylpyruvate reductase (HPPR) is an enzyme involved in the biosynthesis of rosmarinic acid in Lamiaceae reducing hydroxyphenylpyruvates in dependence of NAD(P)H to the corresponding hydroxyphenyllactates. The HPPR protein was purified from suspension cells of Coleus blumei accumulating hi ... >> More

  Hydroxyphenylpyruvate reductase (HPPR) is an enzyme involved in the biosynthesis of rosmarinic acid in Lamiaceae reducing hydroxyphenylpyruvates in dependence of NAD(P)H to the corresponding hydroxyphenyllactates. The HPPR protein was purified from suspension cells of Coleus blumei accumulating high levels of rosmarinic acid by ammonium sulfate precipitation, anion exchange chromatography, hydroxylapatite chromatography, chromatography on 2',5'-ADP-Sepharose 4B and SDS-polyacrylamide gel electrophoresis. The protein was tryptically digested and the peptides sequenced. Sequence information was used to isolate a full-length cDNA-clone for HPPR (EMBL accession number AJ507733) by RT-PCR, screening of a C. blumei cDNA-library and 5'-RACE-PCR. The open reading frame of the HPPR-cDNA consists of 939 nucleotides encoding a protein of 313 amino acid residues. The sequence showed that HPPR belongs to the family of D-isomer-specific 2-hydroxyacid dehydrogenases. The HPPR-cDNA was heterologously expressed in Escherichia coli and the protein was shown to catalyse the NAD(P)H-dependent reduction of 4-hydroxyphenylpyruvate to 4-hydroxyphenyllactate and 3,4-dihydroxyphenylpyruvate to 3,4-dihydroxyphenyllactate. << Less

  Plant Mol. Biol. 54:311-323(2004) [PubMed] [EuropePMC]

  This publication is cited by 3 other entries.

• HPPR encodes the hydroxyphenylpyruvate reductase required for the biosynthesis of hydrophilic phenolic acids in Salvia miltiorrhiza.

  Wang G.Q., Chen J.F., Yi B., Tan H.X., Zhang L., Chen W.S.

  Salvia miltiorrhiza is a medicinal plant widely used in the treatment of cardiovascular and cerebrovascular diseases. Hydrophilic phenolic acids, including rosmarinic acid (RA) and lithospermic acid B (LAB), are its primary medicinal ingredients. However, the biosynthetic pathway of RA and LAB in ... >> More

  Salvia miltiorrhiza is a medicinal plant widely used in the treatment of cardiovascular and cerebrovascular diseases. Hydrophilic phenolic acids, including rosmarinic acid (RA) and lithospermic acid B (LAB), are its primary medicinal ingredients. However, the biosynthetic pathway of RA and LAB in S. miltiorrhiza is still poorly understood. In the present study, we accomplished the isolation and characterization of a novel S. miltiorrhiza Hydroxyphenylpyruvate reductase (HPPR) gene, SmHPPR, which plays an important role in the biosynthesis of RA. SmHPPR contained a putative catalytic domain and a NAD(P)H-binding motif. The recombinant SmHPPR enzyme exhibited high HPPR activity, converting 4-hydroxyphenylpyruvic acid (pHPP) to 4-hydroxyphenyllactic acid (pHPL), and exhibited the highest affinity for substrate 4-hydroxyphenylpyruvate. SmHPPR expression could be induced by various treatments, including SA, GA₃, MeJA and Ag⁺, and the changes in SmHPPR activity were correlated well with hydrophilic phenolic acid accumulation. SmHPPR was localized in cytoplasm, most likely close to the cytosolic NADPH-dependent hydroxypyruvate reductase active in photorespiration. In addition, the transgenic S. miltiorrhiza hairy roots overexpressing SmHPPR exhibited up to 10-fold increases in the products of hydrophilic phenolic acid pathway. In conclusion, our findings provide a new insight into the synthesis of active pharmaceutical compounds at molecular level. << Less

  Chin J Nat Med 15:917-927(2017) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Nontargeted in vitro metabolomics for high-throughput identification of novel enzymes in Escherichia coli.

  Sevin D.C., Fuhrer T., Zamboni N., Sauer U.

  Our understanding of metabolism is limited by a lack of knowledge about the functions of many enzymes. Here, we develop a high-throughput mass spectrometry approach to comprehensively profile proteins for in vitro enzymatic activity. Overexpressed or purified proteins are incubated in a supplement ... >> More

  Our understanding of metabolism is limited by a lack of knowledge about the functions of many enzymes. Here, we develop a high-throughput mass spectrometry approach to comprehensively profile proteins for in vitro enzymatic activity. Overexpressed or purified proteins are incubated in a supplemented metabolome extract containing hundreds of biologically relevant candidate substrates, and accumulating and depleting metabolites are determined by nontargeted mass spectrometry. By combining chemometrics and database approaches, we established an automated pipeline for unbiased annotation of the functions of novel enzymes. In screening all 1,275 functionally uncharacterized Escherichia coli proteins, we discovered 241 potential novel enzymes, 12 of which we experimentally validated. Our high-throughput in vitro metabolomics method is generally applicable to any purified protein or crude cell lysate of its overexpression host and enables performing up to 1,200 nontargeted enzyme assays per working day. << Less

  Nat. Methods 14:187-194(2017) [PubMed] [EuropePMC]

  This publication is cited by 30 other entries.

• Molecular cloning and characterization of tyrosine aminotransferase and hydroxyphenylpyruvate reductase, and rosmarinic acid accumulation in Scutellaria baicalensis.

  Kim Y.B., Uddina M.R., Kim Y., Park C.G., Park S.U.

  Rosmarinic acid (a-O-caffeoyl-3,4-dihydroxyphenylacetic acid, RA) is a caffeoyl ester widely distributed in plants. cDNA clones encoding tyrosine aminotransferase (TAT1 and 2) and hydroxyphenylpyruvate reductase (HPPR) have been isolated from Scutellaria baicalensis. The open reading frames (ORFs) ... >> More

  Rosmarinic acid (a-O-caffeoyl-3,4-dihydroxyphenylacetic acid, RA) is a caffeoyl ester widely distributed in plants. cDNA clones encoding tyrosine aminotransferase (TAT1 and 2) and hydroxyphenylpyruvate reductase (HPPR) have been isolated from Scutellaria baicalensis. The open reading frames (ORFs) of SbTAT1 and 2 were 1230 and 1272 bp long and encoded 409 and 423 amino acid residues, respectively. HPPR corresponded to a 942-bp ORF and 313 amino acid residues of translated protein. To study the molecular mechanisms of TAT and HPPR and investigate RA accumulation in S. baicalensis, we examined the transcript levels of TAT isoforms and HPPR with quantitative real-time PCR and analyzed the RA content in different organs by using high-performance liquid chromatography. The transcript levels of SbTATI SbTAT2, and SbHPPR in the flowers were higher than those in other organs. RA was also highly accumulated in the flowers and with a trace amount in the roots. No RA was detected in the leaves and stems of S. baicalensis. The amount of accumulated RA in the flowers was 28.7 times higher than that in the roots. Our results will be helpful in elucidating the mechanisms of RA biosynthesis in S. baicalensis. << Less

  Nat Prod Commun 9:1311-1314(2014) [PubMed] [EuropePMC]

  This publication is cited by 3 other entries.