Pyridoxal phosphate: biosynthesis and catabolism

FIGURE 15–7 Biosynthesis of phenylalanine and tyrosine from chorismate inbacteria and plants. Conversion of chorismate to prephenate is a rare biologicalexample of a Claisen rearrangement.

Pyridoxal phosphate: biosynthesis and catabolism.

oa Comparative genomics of pyridoxal 5′-phosphate-dependent transcription factor regulons ..

Biosynthesis Of Amino Acids - PEOI

In addition to their role as the building blocks of proteins,amino acids are precursors of many specialized biomolecules,including hormones, coenzymes, nucleotides,alkaloids, cell wall polymers, porphyrins, antibiotics,pigments, and neurotransmitters. We describe here thepathways to a number of these amino acid derivatives.

Pyridoxyl phosphate | CAS#54-47-7 | purinergic P2 …

FIGURE 15–10 Biosynthesis of δ-aminolevulinate. (a) In mammalsand other higher eukaryotes, δ-aminolevulinate is synthesized fromglycine and succinyl-CoA. The atoms furnished by glycine are shownin red. (b) In bacteria and plants, the precursor of δ-aminolevulinateis glutamate. (c) Biosynthesis of heme from δ-aminolevulinate.


Nitric Oxide Synthesis and Function

FIGURE 15–6 Tryptophan synthase reaction. This enzyme catalyzes amultistep reaction with several types of chemical rearrangements.
1) An aldol cleavage produces indole and glyceraldehyde 3-phosphate; thisreaction does not require PLP.
2) Dehydration of serine forms a PLP-aminoacrylate intermediate.
3) and 4) PLP-aminoacrylate condenses with indole.
5) the product is hydrolyzed to release tryptophan.
These PLP-facilitated transformations occur at the β carbon (C-3) of the aminoacid. The β carbon of serine is attached to the indole ring system. TryptophanSynthase Mechanism.

Semester Paper | Biochemistry for Medics – Lecture Notes

Vol. 7: COFACTORS
Edited by Tadhg Begley
vitamins and enzymatic co-factors, including riboflavin biosynthesis, genomics, and enzymology of NAD biosynthesis; pyridoxal phosphate biosynthesis; cofactor catabolism

Amino Acid Synthesis and Metabolism

Vitamin B6 – composed of 3 structures: pyridoxine, pyridoxal, pyridoxamine. The active form pyridoxal 5′-phosphate is a cofactor in many enzyme reactions such as amino acid metabolism that includes neurotransmitters biosynthesis.

Metabolism – Proteins | Biochemistry for Medics – …

FIGURE 15–9 Interlocking regulatory mechanisms in the biosynthesisof several amino acids derived from aspartate in E. coli. Threeenzymes (A, B, C) have either two or three isozyme forms, indicatedby numerical subscripts. In each case, one isozyme (A2, B1, and C2)has no allosteric regulation; these isozymes are regulated by changesin the amount synthesized. Synthesis of isozymes A2 andB1 is repressed when methionine levels are high, and synthesis ofisozyme C2 is repressed when isoleucine levels are high. Enzyme Ais aspartokinase; B, homoserine dehydrogenase; C, threonine dehydratase.

⇑ Back to the top ⇑ Regulation of gluconeogenesis

FIGURE 15–13 Biosynthesis of some neurotransmitters from aminoacids. The key step is the same in each case: a PLP-dependent decarboxylation(shaded in pink).