Where results make sense

About us   |   Why use us?   |   Reviews   |   PR   |   Contact us

Vitamin B6 In the case of pyridoxal, the 4 position of the parent compound is occupied by a formyl group. Serine hydroxymethyltransferase is a pyridoxal 5'-phosphate-dependent enzyme which catalyzes the interconversion of serine and glycine, both of which are major sources of one-carbon units necessary for the synthesis of purine nucleotides and thymidylate. In the liver, pyridoxine, pyridoxal and pyridoxamine are metabolized to pyridoxine 5'-phosphate, pyridoxal 5'-phosphate and pyridoxamine 5'-phosphate, by pyridoxal 5'-phosphate kinase. www.pdrhealth.com /drug_info/nmdrugprofiles/nutsupdrugs/vit_0215.shtml   (4450 words)

Pyridoxal-phosphate - Wikipedia, the free encyclopedia It is the active form of vitamin B It is produced from pyridoxal by the enzyme pyridoxal kinase, and it requires one ATP. It is also found on glycogen phosphorylase in the liver, where it is used to break down glycogen when glucagon or epinephrine signals it to do so. en.wikipedia.org /wiki/Pyridoxal-phosphate   (228 words)

Mullins/SJBR Pyridoxal phosphate is the active form of pyridoxine (vitamin B6). The presence of pyridoxal phosphate stabilizes the carbanion intermediate that is formed during the removal of the carboxyl group (Nelson, Cox, 2000). To confirm the proposed mechanism that binding affinity of glutamic acid decarboxylase and pyridoxal phosphate is low, the pyridoxal phosphate and GABA levels were tested in the skin fibroblasts of the patient with pyridoxine-dependent epilepsy, and compared against five controls. wwwchem.csustan.edu /chem4400/sjbr/Mullins02.htm   (1911 words)

B6-pyridoxal   (Site not responding. Last check: 2007-11-06) Pyridoxal phosphate functions as a cofactor in enzymes involved in transamination reactions required for the synthesis and catabolism of the amino acids. Pyridoxal phosphate is required for the synthesis of delta aminolevulinic acid, a precursor of heme. Pyridoxal phosphate is one of the cofactor required for conversion of tryptophan to NAD. pune.sancharnet.in /spr_keshri/b6.htm   (764 words)

title Pyridoxal Phosphate is used as a coenzyme in the transamination process for the synthesis of amino acids. Pyridoxal phosphate is also involved, as a co-enzyme, in more than sixty enzymic reactions within the body. Pyridoxal phosphate functions as a co-enzyme by virtue of the ability of its aldehyde group to react with the amino group of the amino acid substrate to yield a schiff's base between the enzyme-bound pyridoxal phosphate and the amino acid. my.cybersoup.com /thembi/pyridoxin.html   (343 words)

Pyridoxal phosphate antagonists - Aminotransferase Reactions - HORT640 - Metabolic Plant Physiology - Department of ... Pyridoxal phosphate antagonists - Aminotransferase Reactions - HORT640 - Metabolic Plant Physiology - Department of Horticulture and Landscape Architecture - Purdue University See three dimensional structure of chicken heart, mitochondrial aspartate aminotransferase, showing the interaction between pyridoxal phosphate and the key lysine residue at the catalytic site of each subunit. John RA, Charteris A, Fowler LJ 1978 The reaction of amino-oxyacetate with pyridoxal phosphate-dependent enzymes. www.hort.purdue.edu /rhodcv/hort640c/aminotr/am00007.htm   (74 words)

Synthesis of cross-links in the helical domain of collagen using pyridoxal 5-phosphate and copper or iron - Patent ... Aldehyde cross-link intermediates and cross-links are generated in the central helical portion of collagen by incubating collagen with pyridoxal-5-phosphate and either cupric copper ion or ferrous iron ion. Pyridoxal is then removed by dialysis and cross-links can be formed upon further incubation of the collagen fibrils, or when emplaced into a subject at body temperatures. In all instances, the metal ion and pyridoxal are removed from the collagen after the incubation is terminated. www.freepatentsonline.com /4544638.html   (3763 words)

Pyridoxal 5 Phosphate P5P Pyridoxine Vitamin B6 : by Ray Sahelian, M.D. Vitamin B6 status was assessed via plasma and erythrocyte pyridoxal 5 phosphate concentrations, the erythrocyte aspartate aminotransferase activity coefficient (alphaEAST), net homocysteine increase in response to a methionine load test (DeltatHcy), and 24 h urinary xanthurenic acid (XA) excretion in response to a tryptophan load test. The B6 coenzymes, composed of pyridoxal 5 phosphate (PLP) and pyridoxamine 5'-phosphate (PMP), are used by many transaminases, racemases, decarboxylases, and enzymes catalyzing alpha,beta and beta,gamma-eliminations. Inhibition of acetyl-CoA carboxylase isoforms by pyridoxal phosphate. www.raysahelian.com /pyridoxal5phophatep5p.html   (1517 words)

BD - Diagnostic Systems: Chocolate II Agar with Pyridoxal Chocolate II Agar is an improved medium for use in qualitative procedures for the isolation and cultivation of fastidious microorganisms. Chocolate II Agar supplemented with pyridoxal may be used for this purpose. Chocolate II Agar with Pyridoxal is Chocolate II Agar modified by the addition of 0.01 g/L of pyridoxal. www.bd.com /ds/productCenter/297259.asp   (959 words)

Pyridoxal phosphate is better than pyridoxine for controlling idiopathic intractable epilepsy -- Wang et al. 90 (5): ... and pyridoxamine phosphate are oxidised to pyridoxal phosphate IIE, idiopathic intractable epilepsy; PLP, pyridoxal phosphate; PN, pyridoxine. Pyridoxal phosphate responsive epilepsy, with resistance to pyridoxine. adc.bmjjournals.com /cgi/content/full/90/5/512   (2438 words)

Hypoallergenic Pyridoxal 5-Phosphate Capsules (P-5-P) Pyridoxal 5-Phosphate (P-5-P) is the metabolic/coenzyme form of Vitamin B-6 (Pyridoxine). When vitamin B-6 is ingested, it is converted into pyridoxal 5-phosphate in the liver. Taking B-6 in the pyridoxal phosphate form seems to benefit certain individuals. www.kirkmanlabs.com /products/specialty/p5p/p5p_097.html   (89 words)

Arthritis Research & Therapy | Full text | Inflammation causes tissue-specific depletion of vitamin B6 A recent study indicated that low plasma concentrations of pyridoxal 5'-phosphate are inversely related to major markers of inflammation and independently associated with increased coronary artery disease in the Italian population [11]. Erythrocyte and plasma pyridoxal 5'-phosphate concentrations were assayed by a modification of the tyrosine decarboxylase enzymatic procedure of Camp and colleagues [18], in which a 20 μL aliquot of sample was precipitated with 80 μL of 5% (w/v) trichloroacetic acid for deproteinization. In human subjects, despite the significantly lower pyridoxal 5'-phosphate in plasma (and possibly in liver), erythrocyte pyridoxal 5'-phosphate seemed to be adequate in patients with rheumatoid arthritis, because no difference was found between patients and healthy controls in the erythrocyte pyridoxal 5'-phosphate level or the activity coefficient of erythrocyte aspartate aminotransferase (Table 4). arthritis-research.com /content/7/6/R1254   (5307 words)

chem327lab4-4 Since the reaction is with the unprotonated form of the amino group, reaction with pyridoxal 5' phosphate at neutral or slightly basis pH [pH 7-8] indicates that the pK of the amino group has been significantly shifted to a lower pK. Similarly, ligands that may bind elsewhere to the protein may change the reactivity of such a lysine residue by changing the local environment of the reactive lysine: changes in the rate of reaction [particularly increases in the rate of the reaction] can thus be used to infer conformational changes induced by such ligands. As appropriate, plot the pseudo first order rate constant as a function of the concentration of Pyridoxal 5' Phosphate and calculate the second order rate constant for the inactivation, or construct a graph showing the impact of added ligands or combinations of ligands on the rate of inactivation of Glutamate Dehydrogenase by Pyridoxal 5' Phosphate. www.richmond.edu /~jbell2/chem327lab4-4.html   (1005 words)

Pyridoxal - SHOP.COM Pyridoxal 5-Phosphate P5P 60 vegicaps, FoodScience Of Vermont Pyridoxal-5-Phosphate (P5P) is the active form (does not require activation by the liver) of Vitamin B6 to provide optimal utilization. Pyridoxal 5-Phosphate (P5P) is the active form (does not require activation by the liver) of Vitamin B6 to provide optimal... www.shop.com /op/aprod-~Pyridoxal?SourceID=12   (791 words)

P-5-P B-6 Conversion Process May Be Interrupted by Metabolic Disorders, Certain Conditions or Drugs The usual form of supplementation is with pyridoxine hydrochloride which, under normal conditions, is converted to the phosphorylated pyridoxal within the cells. In humans and other mammals, the phosphorylation enzyme, pyridoxal kinase, is preferentially activated by zinc and/or magnesium. Absorption of amino acids through the intestinal mucosa directly involves the pyridoxal phosphate form of vitamin B-6; therefore, when amino acids are supplemented for the reason of measured deficiency, it is good practice to supplement with P-5-P as well. www.vitasentials.com /p5p.htm   (865 words)

Vitamin B6 Deficiency | AHealthyMe.com During the process of digestion, the phosphate group is removed, and pyridoxal is produced. However, the body readily absorbs pyridoxal, and converts it back to the active form of the vitamin (pyridoxal phosphate). A known quantity of pure pyridoxal phosphate is added to one of the test tubes. www.ahealthyme.com /topic/topic100587661   (861 words)

pyridoxal phosphate - HighBeam Encyclopedia   (Site not responding. Last check: 2007-11-06) PYRIDOXAL PHOSPHATE [pyridoxal phosphate] : see coenzyme ; vitamin. Find newspaper and magazine articles plus images and maps related to "pyridoxal phosphate" at HighBeam. Pyridoxal phosphate more effective than pyridoxine for childhood epilepsy. www.encyclopedia.com /doc/1E1-x-pyridoxa.html   (144 words)

Vitamin B-6   (Site not responding. Last check: 2007-11-06) Within the next few years, I. Gunsalus, E. Snell, A. Braunstein and others demonstrated that a phosphoric derivative of pyridoxal, later identified as pyridoxal 5'-phosphate (II; R = -CHO), is the coenzyme of a large group of specific enzymes catalysing reactions of amino-group transfer, decarboxylation and other metabolic transformations of individual amino acids. In the IUPAC Definitive Rules for the Nomenclature of Vitamins, published in 1960 [4], the term "pyridoxine" was recommended as a generic designation of the B-6 vitamins, and "pyridoxol" as the trivial name for the alcohol form (I; R = -CH OH) previously designated as pyridoxine (Rule V-7). The 5'-phosphoric esters of pyridoxine, pyridoxal and pyridoxamine (II; R = -CH) should be designated pyridoxine 5'-phosphate (or pyridoxine-5'-P), pyridoxal 5'-phosphate (or pyridoxal-5'-P) and pyridoxamine 5'-phosphate (or pyridoxamine-5'-P) respectively. www.chem.qmul.ac.uk /iupac/misc/B6.html   (1357 words)

Clinical Trial: Chelation Therapy of Iron Overload With Pyridoxal Isonicotinoyl Hydrazone To demonstrate the safety and effectiveness of orally-administered pyridoxal isonicotinoyl hydrazone (PIH) for the chronic treatment of iron overload. It is easily produced by the Schiff base condensation of two widely used, inexpensive drugs, vitamin B-6 (pyridoxal) and the antituberculous agent isoniazid. The recent Phase I studies of low-dose PIH in healthy controls and volunteers with iron overload have found no evidence of toxicity while producing an amount of iron excretion that would be clinically useful in the treatment of non-transfusion-dependent patients with iron-loading anemias. clinicaltrials.gov /ct/show/NCT00000588   (861 words)

Effect of Phosphate on Stability of Pyridoxal in the Presence of Lysine   (Site not responding. Last check: 2007-11-06) Model systems composed of equal molar concentrations of lysine with either pyridoxal or pyridoxal phosphate were used to study the effect of proton transfer on Schiff base formation. Quantitation of residual pyridoxal and pyridoxal phosphate was conducted using an HPLC to evaluate the degradation of pyridoxal and pyridoxal phosphate. The deterioration rate of pyridoxal phosphate was faster than that of pyridoxal in an aqueous system. pubs.acs.org /cgi-bin/abstract.cgi/jafcau/2001/49/i03/abs/jf000886q.html   (281 words)

Pyridoxal 5'-phosphate inactivates DNA topoisomerase IB by modifying the lysine general acid -- Vermeersch et al. 32 ... Pyridoxal 5'-phosphate inactivates DNA topoisomerase IB by modifying the lysine general acid -- Vermeersch et al. Pyridoxal 5'-phosphate inhibition of DNA polymerase and DNA primase activities of the DNA polymerase alpha complex from Drosophila melanogaster embryos. Modak,M.J. ((1976)) Observations on the pyridoxal 5'-phosphate inhibition of DNA polymerases. nar.oxfordjournals.org /cgi/content/full/32/18/5649   (5302 words)

Pyridoxal-5-Phosphate Pyridoxal 5-Phosphate (P5P) is the active form (does not require activation by the liver) of Vitamin B6 to provide optimal utilization. It is also required by the nervous system and is a necessary cofactor in managing homocysteine levels, thus promoting cardiovascular health.* No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or other wise, without prior written permission of the copyright owner. www.fslabs.com /p5p.html   (129 words)

Products: Pyridoxal - 5 - Phosphate - The Way Up Pyridoxal - 5 - Phosphate - CoEnzyme B6 Intake is frequently low & this nutrient is commonly deficient in pregnant women, children, the elderly & the ill. It is also depleted by birth control pills, alcohol, tobacco, some antibiotics, blood pressure medication, and numerous other prescription drugs. Without adequate vitamin B6, the amino acids in dietary protein are not of much use to you. Pyridoxal - 5 - Phosphate - CoEnzyme B6 www.thewayup.com /products/0004.cfm   (345 words)

An in vivo evaluation of iron-chelating drugs derived from pyridoxal and its analogs -- Johnson et al. 221 (2): 399 -- ... An in vivo evaluation of iron-chelating drugs derived from pyridoxal and its analogs -- Johnson et al. pyridoxal isonicotinoyl hydrazone, were screened for their effects on iron Pyridoxal itself induced significant iron excretion when given jpet.aspetjournals.org /cgi/content/abstract/221/2/399   (329 words)

Brain pyridoxal kinase. Purification, substrate specificities, and sensitized photodestruction of an essential ... Pyridoxal kinase has been purified 2,000-fold from pig brain. Pyridoxamine is not a substrate of the purified kinase. It is postulated that histidine is involved in the binding of the substrate www.jbc.org /cgi/content/abstract/254/14/6489   (292 words)

Effects of Buffers on Aspartate Aminotransferase Activity and Association of the Enzyme with Pyridoxal Phosphate -- Rej ... Effects of Buffers on Aspartate Aminotransferase Activity and Association of the Enzyme with Pyridoxal Phosphate -- Rej and Vanderlinde 21 (11): 1585 -- Clinical Chemistry Effects of Buffers on Aspartate Aminotransferase Activity and Association of the Enzyme with Pyridoxal Phosphate pyridoxal phosphate was 4% greater than that in phosphate and www.clinchem.org /cgi/content/abstract/21/11/1585   (262 words)

Infotrieve Online   (Site not responding. Last check: 2007-11-06) Crystal structure of pyridoxal kinase from the Escherichia coli pdxK gene: implications for the classification of pyridoxal kinases. The structures were determined in the unliganded and binary complexes with either MgATP or pyridoxal to 2.1-, 2.6-, and 3.2-A resolutions, respectively. Unlike sheep pyridoxal kinase, ePL kinase 1 may not tolerate wide variation in the size and chemical nature of the 4' substituent on the substrate. www4.infotrieve.com /newmedline/detail.asp?NameID=16740960&Session=&searchQuery=Pyridoxal+Phosphate&count=6143   (304 words)

e-Prints Soton - Pyridoxal phosphate de-activation by pyrroline-5-carboxylic acid: increased risk of vitamin B-6 ... We hypothesized that pyridoxal phosphate (vitamin B-6 coenzyme) was de-activated by L-Delta (1)-pyrroline-5-carboxylic acid, the major intermediate that accumulates endogenously in hyperprolinemia type II. These were the result of a Claisen condensation (or Knoevenagel type of reaction) of the activated C-4 carbon of the pyrroline ring with the aldehyde carbon of pyridoxal phosphate. The structures of the adducts were confirmed by a combination of high performance liquid chromatography, nuclear magnetic resonance, and mass spectrometry. eprints.soton.ac.uk /19474   (341 words)

Olympus Microscopy Resource Center: Polarized Light Microscopy Gallery - Vitamin B6 In 1938, pyridoxine became the first form of vitamin B6 to be isolated, and the following year it was the first to be synthesized in a laboratory. It was not until the 1940s that pyridoxal and pyridoxamine were discovered, although they contribute more to bodily vitamin B6 activity than does pyridoxine. The function of the B6 vitamins in their coenzyme form is only vaguely understood, but is, nevertheless, very important. olympusmicro.com /galleries/polarizedlight/pages/vitaminb6small.html   (287 words)

Try your search on: Qwika (all wikis)

About us   |   Why use us?   |   Reviews   |   Press   |   Contact us   Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.