The Biosynthesis of Histidine
It was later shown (2) that the mutant C84 accumulates imidazoleglycerol’ in the growth medium, that mutant Cl41 accumulates imidazoleglycerol and imidazoleacetol,2 and that T1710 accumulates L-histidinol.3 It was also observed that none of these compounds will replace histidine in promoting the growth of these mutants or other mutants blocked earlier in the sequence. This suggested that these imidazole compounds might be derived from biosynthetic intermediates such as phosphate esters to which Neurospora mycelium is impermeable. Preliminary evidence that certain of these mutants do accumulate phosphorylated imidazoleglycerol and imidazoleacetol has been presented (2). This is a report on the isolation and characterization of D-erythro-imidazoleglycerol phosphate (IGP), imidazoleacetol phosphate (IAP), and L-histidinol phosphate, which are accumulated in the mycelia of several of these mutants.
Histidine is an amino acid precursor of neuronal histamine. It is evident that peripheral injection of histidine produces effects that resemble to centrally administered histamine. The aim of the present study was to compare the effects of intracerebroventricular (ICV) injection of histamine and inraperitoneal (IP) injection of histidine on food intake in rabbits. ICV injections of histamine (1...متن کامل
Histidine biosynthesis, its regulation and biotechnological application in Corynebacterium glutamicum
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-...متن کامل
Kinetic studies on repression of the enzymes for histidine biosynthesis in Salmonella typhimurium showed that, upon addition of histidine to a derepressed culture, the enzymes became repressed in a temporal sequence which corresponds with the positional sequence of the genes in the histidine operon. This serial pattern of repression occurred under conditions in which the feedback site of the fi...متن کامل
Primary Site of Action of Amitrole in Arabidopsis thaliana Involves Inhibition of Root Elongation but Not of Histidine or Pigment Biosynthesis.
Interference with histidine metabolism, inhibition of pigment biosynthesis, or both have been the principal candidates for the primary site of action of 3-amino 1,2,4-triazole (amitrole). Arabidopsis thaliana is sensitive to 1,2,4-triazole-3-alanine, a feedback inhibitor of histidine biosynthesis, and this effect is reversed by histidine. The combination of triazolealanine and histidine, howeve...متن کامل
Solvent effects on protonation and complexation of histidine with molybdenum (VI) at different aqueous solutions of methanol
The formation constants of the species formed in the systems H+ + Mo(VI) + histidine and H+ +histidine have been determined at different aqueous solutions of methanol (0 - 45 % v/v) at 25 °C andconstant ionic strength (0.1 mol dm-3 sodium perchlorate), using a combination of spectrophotometricand potentiometric techniques. The composition of the complex species was determined by thecontinuous v...متن کامل
Chain initiation in a polycistronic message: sequential versus simultaneous derepression of the enzymes for histidine biosynthesis in Salmonella typhimurium.
The pathway for histidine biosynthesis in Salmonella typhimurium, elucidated largely through the efforts of Dr. B. N. Ames and co-workers,1-5 is shown in Figure 1. The figure also shows that portion of the pathway for purine biosynthesis which involves the further metabolism of 4-amino-5-imidazole carboxamide ribonucleotide (phosphoribosyl-AIC).6 Dr. Phillip Hartman and his colleagues have show...متن کامل