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Csaba Paizs - One of the best experts on this subject based on the ideXlab platform.
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The production of l - and d -phenylalanines using engineered phenylalanine ammonia lyases from Petroselinum Crispum
Scientific Reports, 2019Co-Authors: Souad Diana Tork, Emma Zsofia Aletta Nagy, Csaba Paizs, Monica Ioana Tosa, Lilla Cserepes, Diana Monica Bordea, Botond Nagy, László Csaba BenczeAbstract:The biocatalytic synthesis of l- and d-phenylalanine analogues of high synthetic value have been developed using as biocatalysts mutant variants of phenylalanine ammonia lyase from Petroselinum Crispum (PcPAL), specifically tailored towards mono-substituted phenylalanine and cinnamic acid substrates. The catalytic performance of the engineered PcPAL variants was optimized within the ammonia elimination and ammonia addition reactions, focusing on the effect of substrate concentration, biocatalyst:substrate ratio, reaction buffer and reaction time, on the conversion and enantiomeric excess values. The optimal conditions provided an efficient preparative scale biocatalytic procedure of valuable phenylalanines, such as (S)-m-methoxyphenylalanine (Y = 40%, ee > 99%), (S)-p-bromophenylalanine (Y = 82%, ee > 99%), (S)-m-(trifluoromethyl)phenylalanine (Y = 26%, ee > 99%), (R)-p-methylphenylalanine, (Y = 49%, ee = 95%) and (R)-m-(trifluoromethyl)phenylalanine (Y = 34%, ee = 93%).
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mapping the hydrophobic substrate binding site of phenylalanine ammonia lyase from Petroselinum Crispum
ACS Catalysis, 2019Co-Authors: Emma Zsofia Aletta Nagy, Souad Diana Tork, Pauline A Lang, Alina Filip, Florin Dan Irimie, Laszlo Poppe, Jurgen Brem, Christopher J. Schofield, Monica Ioana Tosa, Csaba PaizsAbstract:Modification of the hydrophobic binding pocket of phenylalanine ammonia-lyase from Petroselinum Crispum (PcPAL) enables increased activity and selectivity toward phenylalanines and cinnamic acids m...
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Tailored Mutants of Phenylalanine Ammonia-Lyase from Petroselinum Crispum for the Synthesis of Bulky l- and d-Arylalanines.
ChemCatChem, 2018Co-Authors: Alina Filip, Emma Zsofia Aletta Nagy, Souad Diana Tork, Florin Dan Irimie, Laszlo Poppe, Csaba Paizs, Monica Ioana Tosa, Gergely Bánóczi, László Csaba BenczeAbstract:Tailored mutants of phenylalanine ammonia-lyase from Petroselinum Crispum (PcPAL) were created and tested in ammonia elimination from various sterically demanding, non-natural analogues of phenylalanine and in ammonia addition reactions into the corresponding (E)-arylacrylates. The wild-type PcPAL was inert or exhibited quite poor conversions in both reactions with all members of the substrate panel. Appropriate single mutations of residue F137 and the highly conserved residue I460 resulted in PcPAL variants that were active in ammonia elimination but still had a poor activity in ammonia addition onto bulky substrates. However, combined mutations that involve I460 besides the well-studied F137 led to mutants that exhibited activity in ammonia addition as well. The synergistic multiple mutations resulted in substantial substrate scope extension of PcPAL and opened up new biocatalytic routes for the synthesis of both enantiomers of valuable phenylalanine analogues, such as (4-methoxyphenyl)-, (napthalen-2-yl)-, ([1,1'-biphenyl]-4-yl)-, (4'-fluoro-[1,1'-biphenyl]-4-yl)-, and (5-phenylthiophene-2-yl)alanines.
Refiye Yanardag - One of the best experts on this subject based on the ideXlab platform.
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Effects of Petroselinum Crispum extract on pancreatic B cells and blood glucose of streptozotocin-induced diabetic rats.
Biological & Pharmaceutical Bulletin, 2003Co-Authors: Refiye Yanardag, Şehnaz Bolkent, Ayse Tabakoğlu-oğuz, Ozlem Ozsoy-sacanAbstract:This study investigated both morphologically and biochemically whether parsley (Petroselinum Crispum), which is used as a folk remedy to decrease blood glucose, has any antidiabetic effect on pancreatic B cells of rats. Parsley extract was given to male diabetic rats. In the diabetic group given parsley extract, it was detected that the number of secretory granules and cells in islets and other morphologic changes were not different from the control diabetic group, while the blood glucose levels in the diabetic group given the plant extract were reduced in comparison to the diabetic group. In addition, a decrease was observed in the weight of the control diabetic group and the diabetic group given the plant extract. It is suggested that the plant therapy can provide blood glucose homeostasis and cannot regenerate B cells of the endocrine pancreas.
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Limited Effects of Parsley (Petroselinum Crispum) on Protein Glycation and Glutathione in Lenses of Streptozotocin-Induced Diabetic Rats
Pharmaceutical Biology, 2001Co-Authors: Füsun Özçelik, Tugba Tunali, Aysen Yarat, Refiye Yanardag, O. Ozsoy, Nesrin Emekli, Ali UstunerAbstract:Parsley (Petroselinum Crispum), which has hypoglycaemic activity, has been used as a folk remedy for diabetes. This study investigated the effect of parsley administration on diabetes-induced impairments in rat lenses. Administration of parsley extract did not prevent a decrease in glutathione nor an increase in protein glycation, although it did significantly prevent an increase in blood glucose. SDS-polyacrylamide gel electrophoresis revealed no significant differences in any protein bands between any of the groups.
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Effect of parsley (Petroselinum Crispum) on the skin of STZ induced diabetic rats.
Phytotherapy Research, 1999Co-Authors: Tugba Tunali, Aysen Yarat, Refiye Yanardag, Füsun Özçelik, O. Ozsoy, Gönül Ergenekon, Nesrin EmekliAbstract:Parsley (Petroselinum Crispum) is one of the medicinal herbs used by diabetics in Turkey and it has been reported to reduce blood glucose. The purpose of this study therefore was to investigate the effect of feeding parsley on diabetes induced impairments in rat skins. Uncontrolled induced diabetes caused significant increases in nonenzymatic glycosylation of skin proteins, lipid peroxidation and blood glucose. Administration of parsley extract did not inhibit these effects except for the increase in blood glucose. SDS-polyacrylamide gel electrophoresis revealed no significant differences in any protein bands between any of the groups.
Klaus Hahlbrock - One of the best experts on this subject based on the ideXlab platform.
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A highly specific pathogen‐responsive promoter element from the immediate‐early activated CMPG1 gene in Petroselinum Crispum
The Plant Journal, 2001Co-Authors: Christoph Kirsch, Elke Logemann, Elmon Schmelzer, Bernadette Lippok, Klaus HahlbrockAbstract:*Summary Within the complex signalling network from pathogen-derived elicitor perception to defense-related gene activation, some immediate-early responding genes may have pivotal roles in downstream transcriptional regulation. We have identified the parsley (Petroselinum Crispum) ELI17 gene as a particularly fast-responding gene possessing a new type of W box-containing, elicitor-responsive promoter element, E17. Highly selective E17-mediated reporter gene expression at pathogen infection sites in transgenic Arabidopsis thaliana plants demonstrated the potential of this promoter element for designing new strategies in resistance breeding as well as for further analysis of the early components of defense-related gene activation mechanisms. The protein encoded by the ELI17 gene exhibits various structural characteristics of established transcription factors and is designated as a CMPG protein according to the first four strictly conserved amino acids defining a newly emerging class of plantspecific proteins.
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a highly specific pathogen responsive promoter element from the immediate early activated cmpg1 gene in Petroselinum Crispum
Plant Journal, 2001Co-Authors: Christoph Kirsch, Elke Logemann, Elmon Schmelzer, Bernadette Lippok, Klaus HahlbrockAbstract:*Summary Within the complex signalling network from pathogen-derived elicitor perception to defense-related gene activation, some immediate-early responding genes may have pivotal roles in downstream transcriptional regulation. We have identified the parsley (Petroselinum Crispum) ELI17 gene as a particularly fast-responding gene possessing a new type of W box-containing, elicitor-responsive promoter element, E17. Highly selective E17-mediated reporter gene expression at pathogen infection sites in transgenic Arabidopsis thaliana plants demonstrated the potential of this promoter element for designing new strategies in resistance breeding as well as for further analysis of the early components of defense-related gene activation mechanisms. The protein encoded by the ELI17 gene exhibits various structural characteristics of established transcription factors and is designated as a CMPG protein according to the first four strictly conserved amino acids defining a newly emerging class of plantspecific proteins.
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Accumulation of phthalides in elicitor-treated cell suspension cultures of Petroselinum Crispum
Phytochemistry, 1999Co-Authors: Jens Hagemeier, Klaus Hahlbrock, Olaf Batz, Jürgen Schmidt, Victor Wray, Dieter StrackAbstract:Abstract The present study describes the effect of a Phytophthora sojae 25-amino acid oligopeptide (Pep25) elicitor on the secondary metabolism of parsley cell cultures ( Petroselinum Crispum L.). HPLC analysis of the accumulated compounds in the elicitor-treated cultures revealed the expected accumulation of furanocoumarins (e.g. marmesin and bergapten) as well as various non-coumarin compounds which have not been described previously to occur in this cell culture. These compounds were isolated by preparative HPLC and identified by spectroscopic methods (MS, NMR) as 5-hydroxy- and 7-hydroxy-3-butylidenephthalides including two novel conjugates of the 7-hydroxy derivative, i.e. 7- O -glucoside and 7- O -(6′-malonylglucoside).
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structural and catalytic properties of the four phenylalanine ammonia lyase isoenzymes from parsley Petroselinum Crispum nym
FEBS Journal, 1994Co-Authors: Christoph Appert, Elke Logemann, Klaus Hahlbrock, Jurg Schmid, Nikolaus AmrheinAbstract:Near-full-length cDNAs for the four phenylalanine ammonia-lyase (PAL) isoenzymes in parsley (Petroselinum Crispum Nym.) were cloned and the complete amino acid sequences deduced. Fusion proteins with glutathione S -transferase were expressed in Escherichia coli, purified and cleaved. All of the resulting phenylalanine ammonia-lyase proteins, as well as the fusion proteins, were catalytically active. The turnover number of one selected isoenzyme, PAL-1, was estimated to be around 22 s−1 for each active site. In contrast to a certain degree of differential expression in various parts of parsley plants, the four phenylalanine ammonia-lyase isoenzymes exhibited very similar apparent Km, values for L-phenylalanine (15–24.5 μM) as well as identical temperature (58° C) and pH (8.5) optima. All of them were competitively inhibited by (E)-cinnamate with similar efficiency (Ki, values: 9.1–21.5 μM), lacked cooperative behaviour, and accepted L-tyrosine as a substrate with low affinity (Km, values: 2.6–7.8 μM). These results suggest that the occurrence of multiple gene copies has a function other than encoding isoenzymes with different enzyme kinetic properties.
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Polyubiquitin gene expression and structural properties of the ubi4-2 gene in Petroselinum Crispum.
Plant Molecular Biology, 1993Co-Authors: Petra Kawalleck, Klaus Hahlbrock, Imre E. Somssich, Michael Feldbrügge, Bernd WeisshaarAbstract:Ubiquitin is an omnipresent protein found in all eukaryotes so far analysed. It is involved in several important processes, including protein turnover, chromosome structure and stress response. Parsley (Petroselinum Crispum) contains at least two active polyubiquitin (ubi4) genes encoding hexameric precursor proteins. The deduced amino acid sequences of the ubiquitin monomers are identical to one another and to ubiquitin sequences from several other plant species. Analysis of the promoter region of one ubi4 gene revealed putative regulatory elements. In parsley plants, the ubi4 mRNAs were the predominant ubiquitin mRNAs and were present at comparable levels in all plant organs tested. In cultured parsley cells, high levels of ubiquitin gene expression remained unaffected by heat shock, elicitor or light treatment.
S Olatunbosun Banjoko - One of the best experts on this subject based on the ideXlab platform.
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Biochemical and haematological assessment of toxic effects of the leaf ethanol extract of Petroselinum Crispum (Mill) Nyman ex A.W. Hill (Parsley) in rats
BMC Complementary and Alternative Medicine, 2013Co-Authors: Emmanuel Olorunju Awe, S Olatunbosun BanjokoAbstract:Background Petroselinum Crispum, a bright green biennial shrub is widely used traditionally as a food additive and herbal remedies for many ailments. This study therefore aimed to assess the toxic effects of its leaf extract using some biochemical, haematological parameters.
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Biochemical and haematological assessment of toxic effects of the leaf ethanol extract of Petroselinum Crispum (Mill) Nyman ex A.W. Hill (Parsley) in rats
BMC Complementary and Alternative Medicine, 2013Co-Authors: S Olatunbosun BanjokoAbstract:Background Petroselinum Crispum, a bright green biennial shrub is widely used traditionally as a food additive and herbal remedies for many ailments. This study therefore aimed to assess the toxic effects of its leaf extract using some biochemical, haematological parameters. Methods The toxic effects were assessed by quantifying liver enzymes such as serum aspartate amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), total serum protein and liver weight. Effects on haematological parameters were assessed by analysis of parked cell volume (PCV), red blood cell count (RBC), white blood cells (WBC) and haemoglobin (Hb) concentrations. Histopathological studies were done on the liver and kidneys. Results The extract caused significant increase in serum activity of alanine amino transferase and blood urea nitrogen (BUN) levels at the dose of 1000 mg/kg. Other biochemical and haematological parameters were not affected at lower doses. Conversely, the liver weight was not affected after eight weeks of treatment at the dose levels studied. The organs obtained for pathological study, were structurally unchanged under histopathological evaluation at lower doses but inflammatory and necrotic features were observed at doses ≥ 1000 mg/kg. Conclusion The results indicate that the leaf ethanol extract of Petroselinum Crispum was hepatotoxic and nephrotoxic at continued oral doses equal to or more than 1000 mg/kg, but no obvious toxicity when used at lower doses. Therefore, there should be caution in its administration to avoid overdosing and known interaction with some medications. In addition, the plant should be kept away from pets and domestic animals and should not be cultivated on soil irrigated with waste water due to their ability to bio-accumulate toxic metals.
Florin Dan Irimie - One of the best experts on this subject based on the ideXlab platform.
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mapping the hydrophobic substrate binding site of phenylalanine ammonia lyase from Petroselinum Crispum
ACS Catalysis, 2019Co-Authors: Emma Zsofia Aletta Nagy, Souad Diana Tork, Pauline A Lang, Alina Filip, Florin Dan Irimie, Laszlo Poppe, Jurgen Brem, Christopher J. Schofield, Monica Ioana Tosa, Csaba PaizsAbstract:Modification of the hydrophobic binding pocket of phenylalanine ammonia-lyase from Petroselinum Crispum (PcPAL) enables increased activity and selectivity toward phenylalanines and cinnamic acids m...
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Mapping the hydrophobic substrate binding site of phenylalanine ammonia lyase from Petroselinum Crispum
'American Chemical Society (ACS)', 2019Co-Authors: Nagy Eza, Souad Diana Tork, Florin Dan Irimie, Monica Ioana Tosa, Pa Lang, Filip A, Poppe L, Cj Schofield, Brem J, Paizs CAbstract:Modification of the hydrophobic binding pocket of phenylalanine ammonia-lyase from Petroselinum Crispum (PcPAL) enables increased activity and selectivity towards phenylalanines and cinnamic acids mono-substituted with both electron donating (-CH3, -OCH3) and electron withdrawing (-CF3, -Br) groups at all positions (o-, m-, p-) of their aromatic ring. The results reveal specific residues involved in accommodating substituents at o-, m-, p-positions of the substrate’s phenyl ring. The predicted interactions were validated by crystallographic analysis of the binding mode of para-methoxy cinnamic acid complexed at the active site of PcPAL. The biocatalytic utility of the tailored PcPAL mutants was demonstrated by the efficient preparative scale synthesis of (S)-m-bromo-phenylalanine (ee: > 99%, yield: 60%) and (R)-p-methyl-phenylalanine (ee: 97%, yield: 49%), using the corresponding ammonia addition and ammonia elimination reactions catalyzed by the L134A and I460V PcPAL variants, respectively. Overall, the results reveal the potential for structure based protein engineering of PALs to provide enzymes with enhanced catalytic properties and which are specifically tailored for differently substituted phenylalanine analogues of high synthetic value
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Tailored Mutants of Phenylalanine Ammonia-Lyase from Petroselinum Crispum for the Synthesis of Bulky l- and d-Arylalanines.
ChemCatChem, 2018Co-Authors: Alina Filip, Emma Zsofia Aletta Nagy, Souad Diana Tork, Florin Dan Irimie, Laszlo Poppe, Csaba Paizs, Monica Ioana Tosa, Gergely Bánóczi, László Csaba BenczeAbstract:Tailored mutants of phenylalanine ammonia-lyase from Petroselinum Crispum (PcPAL) were created and tested in ammonia elimination from various sterically demanding, non-natural analogues of phenylalanine and in ammonia addition reactions into the corresponding (E)-arylacrylates. The wild-type PcPAL was inert or exhibited quite poor conversions in both reactions with all members of the substrate panel. Appropriate single mutations of residue F137 and the highly conserved residue I460 resulted in PcPAL variants that were active in ammonia elimination but still had a poor activity in ammonia addition onto bulky substrates. However, combined mutations that involve I460 besides the well-studied F137 led to mutants that exhibited activity in ammonia addition as well. The synergistic multiple mutations resulted in substantial substrate scope extension of PcPAL and opened up new biocatalytic routes for the synthesis of both enantiomers of valuable phenylalanine analogues, such as (4-methoxyphenyl)-, (napthalen-2-yl)-, ([1,1'-biphenyl]-4-yl)-, (4'-fluoro-[1,1'-biphenyl]-4-yl)-, and (5-phenylthiophene-2-yl)alanines.