Pyridoxal phosphate biochemistry

Walsh C, RA Pascal, M Johnston, R Raines, D Dikshit, A Krantz, M Houma (1981) Mechanistic studies on the pyridoxal phosphate enzyme 1-aminocyclopropane-l-carboxylate deaminase from Pseudomonas sp. Biochemistry 20 7509-7519. 

Shimomura, S., and Fukui, T. (1978) Characterization of the pyridoxal phosphate site in glycogen phos-phorylase b from rabbit muscle. Biochemistry 17, 5359. 

Pyridoxal phosphate is the coenzyme for the enzymic processes of transamination, racemization and decarboxylation of amino-acids, and for several other processes, such as the dehydration of serine and the synthesis of tryptophan that involve amino-acids (Braunstein, 1960). Pyridoxal itself is one of the three active forms of vitamin B6 (Rosenberg, 1945), and its biochemistry was established by 1939, in considerable part by the work of A. E. Braunstein and coworkers in Moscow (Braunstein and Kritzmann, 1947a,b,c Konikova et al 1947). Further, the requirement for the coenzyme by many of the enzymes of amino-acid metabolism had been confirmed by 1945. In addition, at that time, E. E. Snell demonstrated a model reaction (1) for transamination between pyridoxal [1] and glutamic acid, work which certainly carried with it the implication of mechanism (Snell, 1945). 

The vitamin biotin is formed in nature (left) by condensation of L-alanine with pimeloyl-CoAto form 8-amino-7-oxononanoate (AON). This compound is seen at the upper left of the center structure joined as a Schiff base with the coenzyme pyridoxal phosphate (PLP). This is a product complex of the enzyme AON synthase (see Webster et ah, Biochemistry 39,516-528,2000) Courtesy of D. Alexeev,... 

Cidlowski JA and ThanassiJW (1981) Pyridoxal phosphate a possible cofactor in steroid hormone action. Journal of Steroid Biochemistry 15,11-16. 

Zhang F, Thottananiyil M, Martin DL, and Chen CH (1999) Conformational alteration in serum albumin as a carrier for pyridoxal phosphate a distinction from pyridoxal phosphate-dependent glutamate decarboxylase. Archives of Biochemistry and Biophysics 3S4, 195-202. 

The chemistry of the cofactors has provided a fertile area of overlap between organic chemistry and biochemistry, and the organic chemistry of the cofactors is now a thoroughly studied area. In contrast, the chemistry of cofactor biosynthesis is stiU relatively underdeveloped. In this review the biosynthesis of nicotinamide adenine dinucleotide, riboflavin, folate, molyb-dopterin, thiamin, biotin, Upoic acid, pantothenic acid, coenzyme A, S-adenosylmethionine, pyridoxal phosphate, ubiquinone and menaquinone in E. coli will be described with a focus on unsolved mechanistic problems. 

Raetz, C.R., and Auld, D.S. (1972) Schiff bases of pyridoxal phosphate with active center lysines of ribonuclease A. Biochemistry 11,2229-2236. 

This table lists and numbers the reactions mentioned in the text and in Figs. 1-4. Where an enzyme is involved, the systematic name is given as defined by the commission on Biochemical Nomenclature and adopted by the International Union of Biochemistry and the International Union of Pure and Applied Chemistry. With those enzymes having commonly used trivial names, it has been listed in parentheses after the systematic name. In the interests of brevity, the designation of the configuration (l) around the o-carbon is omitted in the equations. Abbreviations used are the same as defined in Journal of Biological Chemistry and are not defined here because of their widespread use. Pyr-P means pyridoxal phosphate. 

Imine formation occtirs in many biochemical reactions because enzymes often use an — NH2 group to react with an aldehyde or ketone. An imine linkage is important in the biochemistry of pyridoxal phosphate (which is related to vitamin Bg see The Chemistry of... box on page 744). 

Eliot, A.C., and Kirsch, J.F., 2004. Pyridoxal phosphate enzymes mechanistic, structural, and evolutionary considerations. Annual Review of Biochemistry. 73 383 15. 

YC Chang, RD Scott, DJ Graves. Function of pyridoxal 5 -phosphate in glycogen phosphorylase F NMR and kinetic studies of phosphorylase reconstituted with 6-fluoropyridoxal and 6-fluoropyridoxal phosphate. Biochemistry 25 1932-1939, 1986. 

Fasella PM (1967) Pyridoxal phosphate. Annual Review of Biochemistry 36 185-210. 

Karthikeyan S, Q Zhou, Z Zhao, C-L Kao, Z Tao, H Robinson, H-w Liu, H Zhang (2004) Structural analysis of Pseudomonas 1-aminocyclopropane-l-carboxylate deaminase complexes insight into the mechanism of a unique pyridoxal-5 -phosphate dependent cyclopropane ring-opening reaction. Biochemistry 43 13328-13339. 

Palm D, Klein HW, Schinzel R, Buehner M, and Helmreich EJ (1990) The role of pyridoxal 5-phosphate in glycogen phosphorylase catalysis. Biochemistry 29,1099-1107. 

Hayashi H, Wada H, Yoshimuia T, Esaki N, and Soda K (1990) Recent topics in pyridoxal 5 -phosphate enzyme studies. Annual Reviews of Biochemistry 59, 87-110. 

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