Search

Your search keyword '"Pipecolic Acids analysis"' showing total 2 results
Start Over Descriptor "Pipecolic Acids analysis" Publisher taylor & francis
2 results on '"Pipecolic Acids analysis"'

1. New amperometric biosensors based on diamond paste for the assay of L- and D-pipecolic acids in serum samples.

Author

Stefan RI, Nejem RM, van Staden JF, and Aboul-Enein HY

Subjects
Biomarkers analysis, Biosensing Techniques instrumentation, Electrochemistry instrumentation, Electrodes, Humans, Infant, Newborn, Infant, Newborn, Diseases diagnosis, Liver Diseases diagnosis, Oils chemistry, Ointments chemistry, Paraffin, Pipecolic Acids blood, Sensitivity and Specificity, Stereoisomerism, Amino Acid Oxidoreductases chemistry, Biosensing Techniques methods, Diamond chemistry, Electrochemistry methods, Pipecolic Acids analysis, Serum chemistry
Abstract

Monocrystalline natural diamond, L-amino acid oxidase (L-AAOD), D-amino acid oxidase (D-AAOD), and paraffin oil were used for the design of the modified diamond paste. The technique used for the direct voltammetric assay was differential pulse voltammetry (DPV) with applied potential pulse amplitude of 25 mV vs. Ag/AgCl. Using the new amperometric biosensors L-pipecolic acid (L-PA) and D-pipecolic acid (D-PA) were determined reliably from serum samples at 700 and 200 mV vs. Ag/AgCl, respectively, with low limits of detection.

Published
2004
Full Text
View/download PDF

2. In vitro biosynthesis of peptolide SDZ 90-215 by a 1.2 MDa multienzyme polypeptide.

Author

Lee C and Lawen A

Subjects
Amino Acid Sequence, Chromatography, High Pressure Liquid, Culture Media, Electrophoresis, Polyacrylamide Gel, Methyltyrosines chemistry, Molecular Sequence Data, Molecular Weight, Multienzyme Complexes chemistry, Multienzyme Complexes isolation & purification, Peptide Synthases chemistry, Peptide Synthases isolation & purification, Peptides, Cyclic chemistry, Peptides, Cyclic isolation & purification, Pipecolic Acids analysis, Tyrosine metabolism, Mitosporic Fungi enzymology, Multienzyme Complexes metabolism, Peptide Synthases metabolism, Peptides, Cyclic biosynthesis
Abstract

An enzyme fraction with catalytic activities for the biosynthesis of the pipecolic acid containing cyclopeptolide SDZ 90-215 was partially purified and characterized from the genus Septoria. The crude cell homogenate was subjected to polyethyleneimine precipitation, ammonium sulfate precipitation and FPLC gel filtration. The denatured enzyme shows an apparent molecular mass of 1.2 MDa in 3% SDS-PAGE. Peptolide SDZ 90-215 synthetase catalyzes the ATP-PPi exchange reaction dependent on all substituent amino and hydroxy acids. SDZ 90-215 synthetase synthesizes the peptolide in vitro when incubated together with D-lactic acid, all constitutive amino acids in their N-unmethylated form, ATP, magnesium chloride and S-adenosyl-L-methionine. The yield of SDZ 90-215 is higher when O-methyl-L-tyrosine instead of L-tyrosine is used, indicating that O-methylation of tyrosine is not carried out by the synthetase.

Published
1993

Catalog

Books, media, physical & digital resources
See catalog results