A fluorescent hydroxyl- and hydrazone-based covalent organic framework (TFPB–DHTH COF) was synthesized as an “OFF–ON” sensor for cysteine l-histidine.

l-Histidine biosynthesis is an ancient metabolic pathway present in bacteria, archaea, lower eukaryotes, and plants. For decades l-histidine biosynthesis has been studied mainly in Escherichia coli and Salmonella typhimurium, revealing fundamental regulatory processes in bacteria. Furthermore, in the last 15 years this pathway has been also investigated intensively in the industrial amino acid-...

The objective of this research was to develop a kinetic-spectrophotometric method for the determination microquantities L-histidine in pure form and dietary supplements. based on kinetics ampicillin degradation by Ni(II) ion as catalyst presence strongly alkaline medium. rate reaction monitored spectrophotometrically measuring increase absorbance at 265 nm function time. same approach used inve...

A simple approach to prepare and characterize biomaterial-based electrocatalysts for oxygen reduction was carried out. Poly-l-histidine was used as a matrix and ligand to complex Cu2+ to mimic the active sites of laccases. A modified glassy carbon (GC) electrode with Cu2+-poly-l-histidine complex decreases the oxygen reduction overpotential as compared with the bare GC electrode. An array of Cu...

In studies on the nature of the enzymic defect in patients with histidinaemia, an inborn error of histidine metabolism (La Du, Howell, Jacoby, Seegmiller & Zannoni, 1962), it was necessary to develop a sensitive assay procedure to measure histidine oc-deaminase (L-histidine ammonia-lyase, EC 4.3.1.3), the enzyme that converts histidine into urocanic acid. The application of this method has show...