Results 221 to 230 of about 5,682 (254)

Kinetics of Protoporphyrinogen Oxidase Inhibition by Diphenyleneiodonium Derivatives

Biochemistry, 1997
Protoporphyrinogen oxidase, the last enzyme of the common branch of the heme and chlorophyll pathways in plants, is the molecular target of diphenyl ether-type herbicides. These compounds inhibit the enzyme competitively with respect to the tetrapyrrole substrate, protoporphyrinogen IX.
S, Arnould, J L, Berthon, C, Hubert, M, Dias, C, Cibert, R, Mornet, J M, Camadro   +6 more
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Antioxidants restore protoporphyrinogen oxidase in variegate porphyria patients

European Journal of Clinical Investigation, 2013
AbstractBackgroundVariegate porphyria (VP) is the result of decreased protoporphyrinogen oxidase (PPOX) activity and results in the accumulation of porphyrins and porphyrin precursors. Our aims were to analyse the basal antioxidant defences and oxidative damage markers and the effects of a diet supplementation with vitamins E and C on the oxidant ...
Miguel D, Ferrer, Pedro, Tauler, Antoni, Sureda, Clara, Palacín, Josep A, Tur, Antoni, Pons   +5 more
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Protoporphyrinogen oxidase and porphobilinogen deaminase in variegate porphyria

European Journal of Clinical Investigation, 1986
Abstract. Two enzymes of the haem biosynthetic pathway were investigated in patients with variegate porphyria. Protoporphyrinogen oxidase in cultures of Epstein‐Barr virus transformed lymphoblasts from twenty‐seven patients showed a mean maximal velocity (Vmax) of 0·39 ± 0·08+ nmol of protoporphyrin mg protein‐1 h‐1, a 52% reduction (P < 0·001 ...
P N, Meissner, R S, Day, M R, Moore, P B, Disler, E, Harley   +4 more
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Cloning, Sequence, and Expression of Mouse Protoporphyrinogen Oxidase

Archives of Biochemistry and Biophysics, 1995
Protoporphyrinogen oxidase (EC 1.3.3.4) is the penultimate enzyme in the heme biosynthetic pathway, catalyzing the six-electron oxidation of protoporphyrinogen to protoporphyrin. A dominantly inherited genetic deficiency in this enzyme results in the disease variegate porphyria.
T A, Dailey, H A, Dailey, P, Meissner, A R, Prasad   +3 more
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Pyrazole phenyl ether herbicides inhibit protoporphyrinogen oxidase

Pesticide Biochemistry and Physiology, 1991
Abstract Two isomeric pairs of pyrazole phenyl ether herbicides [AH 2.429, 4-chloro-1-methyl-5-(4-nitrophenoxy)-3-(trifluoromethyl)-1 H -pyrazole; AH 2.430, 4-chloro-1-methyl-3-(4-nitrophenoxy)-5-(trifluoromethyl)-1 H -pyrazole; AH 2.431, 5-((4-chloro-1-methyl-5-(trifluoromethyl)-1 H -pyrazol-3-yl)oxy)-2-nitrobenzoic acid; and AH 2.432, 5-((4-chloro ...
Timothy D. Sherman, Mary V. Duke, Robert D. Clark, Ernest F. Sanders, Hiroshi Matsumoto, Stephen O. Duke   +5 more
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Expression, purification, and characteristics of mammalian protoporphyrinogen oxidase

1997
Publisher Summary Studies have found that the B. subtilis , M. xanthus , and human protoporphyrinogen oxidase (PPO) complementary DNAs (cDNAs) contains an NH 3 -terminal 6-histidine (His 6 ) tag, which has greatly facilitated their purification and characterization. By using a metal-chelating matrix, it is possible to purify to apparent homogeneity
T A, Dailey, H A, Dailey
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Protoporphyrinogen-IX Oxidase Inhibitors: Bioactivation of Thiadiazolidines

Pesticide Biochemistry and Physiology, 2001
Abstract The bioactivation of thiadiazolidine-type peroxidizing compounds was examined with thiosemicarbazides as model intermediates. Peroxidizing activities of three sets of thiadiazolidines (5-arylimino-3,4-tetramethylene-1,3,4-thiadiazolidines), thiosemicarbazides (4-aryl-1-ethylthiocarbonyl-1,2-tetramethylenethiosemicarbazides), and ...
Masaki Hiraki, Shinpei Ohki, Yukiharu Sato, Istvan Jablonkai, Peter Böger, Ko Wakabayashi   +5 more
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Herbicidal Efficacy of Protoporphyrinogen Oxidase Inhibitors

1999
Compounds which inhibit protoporphyrinogen oxidase (Protox) were known as “photobleaching herbicides” before their site of action was discovered. Photobleaching herbicides cause very strong bleaching of the treated part of higher plants. It was known that a photobleaching herbicide requires oxygen and light to express its herbicidal activity.
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ChemInform Abstract: Synthesis of Protoporphyrinogen Oxidase Inhibitors.

ChemInform, 1994
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
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Photodynamic therapy using a protoporphyrinogen oxidase inhibitor.

Cancer research, 1997
The use of endogenously created porphyrins as an alternative to photosensitizer injection for photodynamic therapy is a rapidly evolving area of study. One common method to induce porphyrin synthesis and accumulation in cells is the topical, oral, or parenteral administration of 5-aminolevulinic acid, a precursor for heme biosynthesis.
V H, Fingar, T J, Wieman, K S, McMahon, P S, Haydon, B P, Halling, D A, Yuhas, J W, Winkelman   +6 more
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