نتایج جستجو برای: expanded porphyrins

تعداد نتایج: 64232  

Journal: :Journal of toxicology and environmental health. Part A 2007
David A Geier Mark R Geier

Porphyrins are derivatives formed in the heme synthesis pathway and porphyrins afford a measure of xenobiotic exposure. The steps in the heme pathway most vulnerable to heavy metal inhibition are uroporphyrin decarboxylase (UROD) and coproporphyrinogen oxidase (CPOX) reactions. Mercury toxicity was associated with elevations in urinary coproporphyrin (cP), pentacarboxyporphyrin (5cxP), and prec...

2005
Vishwanath M. Sardesai

LTHOUGH the primary precursors, the intermediates and most of the enzymes involved ir the biosynthetic chain of porphyrins are now known,’,2’3 knowledge of the tissue sites( s) of porphyrin formation is incomplete. Several earlier studies4’5 demonstrated that avian nucleated erythrocytes as well as rabbit bone marrow are active in this respect. Both tissues utilize either glycine and acetate ( ...

Journal: :Clinical chemistry 1983
W E Schreiber V A Raisys R F Labbé

Information on changes in the urinary excretion pattern of porphyrins can be especially useful in the diagnosis of disorders of porphyrin metabolism. Most clinical laboratory procedures are designed for assay of uroporphyrin and coproporphyrin only, and in many cases even these are not cleanly separated. Hence, we developed a "high-performance" liquid-chromatographic procedure to separate and q...

Journal: :Journal of bacteriology 2007
Cynthia L Richard-Fogal Elaine R Frawley Robert E Feissner Robert G Kranz

Studies have indicated that specific heme delivery to apocytochrome c is a critical feature of the cytochrome c biogenesis pathways called system I and II. To determine directly the heme requirements of each system, including whether other metal porphyrins can be incorporated into cytochromes c, we engineered Escherichia coli so that the natural system I (ccmABCDEFGH) was deleted and exogenous ...

2001
Chin-Ti Chen Gerald R. Meredith

Due to their potential applications for optical communications, data storage, and electrooptical signal processing, molecules with nonlinear optical (NLO) properties have been extensively investigated.’ As part of our interest in porphyrins and metalloporphyrins as photoresponsive2 and field-responsive material^,^ we have synthesized a series of “push-pull” porphyrins containing both donor and ...

Journal: :Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology 2016
Camila Chevonica Vandresen Alan Guilherme Gonçalves Diogo Ricardo Bazan Ducatti Fabio Seigi Murakami Miguel Daniel Noseda Maria Eugenia Rabello Duarte Sandra Mara Woranovicz Barreira

Photodynamic inactivation (PDI) is an efficient approach for the elimination of a series of microorganisms; however, PDI involving phytopathogenic filamentous fungi is scarce in the literature. In the present study, we have demonstrated the photoinactivating properties of five cationic meso-(1-methyl-4-pyridinio)porphyrins on conidia of the phytopathogen Colletotrichum graminicola. For this pur...

Journal: :Photodiagnosis and photodynamic therapy 2014
Aoife A Ryan Mothi M Ebrahim Rosine Petitdemange Gisela M Vaz Edyta Paszko Natalia N Sergeeva Mathias O Senge

Improved photosensitizers for use in photomedicine must possess good water-solubility and optimal photophysical properties. Phosphorus(V) porphyrins fulfill these criteria and are a class of porphyrins with significant potential applications in phototherapy. Five phosphorus(V) porphyrins bearing alkyl substituents have been synthesized. Reasonable to good yields were obtained for all P(V) inser...

Journal: :The Journal of biological chemistry 1953
S GRANICK L BOGORAD H JAFFE

In the preceding paper (1) the isolation and culture of Chlorella WEB-17 was described. Evidence was presented that this mutant produced three dicarboxylic porphyrins in relatively large amounts. In this paper we report the isolation from the porphyrin mixture of one of these dicarboxylic porphyrins and its characterization as hematoporphyrin isomer IX (Fig. 1). Hematoporphyrin has not previous...

Journal: :The Biochemical journal 2000
C K Lim M A Razzaque J Luo P B Farmer

It has been widely reported that the Harderian gland, present in most vertebrates, accumulates high levels of porphyrins, particularly protoporphyrin. The present study describes the extraction, identification and characterization of a group of hitherto unreported protoporphyrin glycoconjugates in the rat Harderian gland using HPLC, capillary electrophoresis, on-line HPLC/electrospray ionizatio...

Journal: :Journal of the American Chemical Society 2007
Woon Ju Song Mi Sook Seo Serena Debeer George Takehiro Ohta Rita Song Min-Jung Kang Takehiko Tosha Teizo Kitagawa Edward I Solomon Wonwoo Nam

The reactions of manganese(III) porphyrin complexes with terminal oxidants, such as m-chloroperbenzoic acid, iodosylarenes, and H(2)O(2), produced high-valent manganese(V)-oxo porphyrins in the presence of base in organic solvents at room temperature. The manganese(V)-oxo porphyrins have been characterized with various spectroscopic techniques, including UV-vis, EPR, 1H and 19F NMR, resonance R...

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