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Pterin function in bacteria [PDF]
Pteridines, 2017 Abstract Pterins are widely conserved biomolecules that play essential roles in diverse organisms. First described as enzymatic cofactors in eukaryotic systems, bacterial pterins were discovered in cyanobacteria soon after. Several pterin structures unique to bacteria have been described, with conjugation to glycosides and nucleotides ...
Nathan Feirer, Clay Fuqua
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Pterin-based pigmentation in animals [PDF]
Biology Letters, 2021 Pterins are one of the major sources of bright coloration in animals. They are produced endogenously, participate in vital physiological processes and serve a variety of signalling functions. Despite their ubiquity in nature, pterin-based pigmentation has received little attention when compared to other major pigment classes.
Pedro Andrade, Miguel Carneiro
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Direct coordination of pterin to Fe II enables neurotransmitter biosynthesis in the pterin-dependent hydroxylases [PDF]
Proceedings of the National Academy of Sciences, 2021 Significance The mononuclear pterin-dependent nonheme iron enzymes catalyze the rate-limiting step in neurotransmitter biosynthesis and are essential in maintaining proper brain function. These enzymes utilize molecular oxygen, a redox active pterin cofactor, and a ferrous active site to generate an Fe IV -
Shyam R. Iyer +13 more
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Journal of Biological Chemistry, 1959 Publisher Summary This chapter describes the bacterial pterin deaminase. In the standard assay, the mixture contains 0.05 ml of pterin carboxylic acid, 0.8 ml of phosphate buffer, and 0.02 to 0.15 ml of enzyme in a final volume of 1.0 ml. Incubation is carried out at 23° in a 1-ml Beckman quartz cuvette with a light path of 1.00 cm. Reaction is begun
Bruce Levenberg, Osamu Hayaishi
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Journal of Biological Chemistry, 1972 Abstract Qualitative and quantitative analyses for pterins (derivatives of 2-amino-4-hydroxypteridine) in human urine were carried out by an improved procedure which involved the use of two new weak ion exchangers, ECTEOLA-Sephadex and phospho-Sephadex.
Tetsuo Shiota, Takeshi Fukushima
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The pterin molybdenum cofactors.
Journal of Biological Chemistry, 1992 crassa, demonstrated that the inactive apoprotein of nitrate reductase in extracts of the mutant could be reconstituted by the addition of denatured preparations of purified molybdoenzymes from animal, fungal, or bacterial origin. This crucial finding showed that mol- ybdoenzymes contain a dissociable entity fitting the description of a cofactor and ...
K.V. Rajagopalan, Jean L. Johnson
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Inactivation of tyrosinase photoinduced by pterin
Biochemical and Biophysical Research Communications, 2012 Tyrosinase catalyzes in mammals the first and rate-limiting step in the biosynthesis of the melanin, the main pigment of the skin. Pterins, heterocyclic compounds able to photoinduce oxidation of DNA and its components, accumulate in the skin of patients suffering from vitiligo, a chronic depigmentation disorder in which the protection against UV ...
Dantola, Maria Laura +2 more
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The Journal of Infectious Diseases, 2021 Abstract Background Cerebral malaria (CM) pathogenesis remains incompletely understood. Having shown low systemic levels of tetrahydrobiopterin (BH4), an enzymatic cofactor for neurotransmitter synthesis, we hypothesized that BH4 and BH4-dependent neurotransmitters would likewise be low in ...
Salvatore M. Florence +14 more
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Tryptophan oxidation photosensitized by pterin
Free Radical Biology and Medicine, 2013 Pterins are normal components of cells and they have been previously identified as good photosensitizers under UV-A irradiation, inducing DNA damage and oxidation of nucleotides. In this work, we have investigated the ability of pterin (Ptr), the parent compound of oxidized pterins, to photosensitize the oxidation of another class of biomolecules ...
Thomas, Andrés +6 more
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Photochemistry of Resveratrol: Beyond the Reactivity of Metal‐Free Porphyrins Immobilized on Lignin
ChemPhotoChem, EarlyView.Resveratrol photochemistry with singlet oxygen is examined at 450 nm using blue‐LED irradiation and various homogeneous and heterogeneous photosensitizers. Products of CC bond cleavage, electrocyclic ring closure, and [4 + 2] cycloaddition are identified.
Elisa De Marchi +8 more
wiley +1 more source