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F Tietze

Bio: F Tietze is an academic researcher from National Institutes of Health. The author has contributed to research in topics: Cystine & Cystinosis. The author has an hindex of 25, co-authored 44 publications receiving 7826 citations. Previous affiliations of F Tietze include University of Colorado Boulder & University of Helsinki.

Papers
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Journal ArticleDOI
TL;DR: The use of the foregoing analytical method in the determination of total and oxidized glutathione contents of rat blood, kidney, and liver gave values in good agreement with those obtained by previous investigators.

5,900 citations

Journal ArticleDOI
24 Sep 1982-Science
TL;DR: The activity of a cystine transport system in lysosomes prepared from the leukocytes of patients with cystinosis was found to be deficient and this system was resistant to N-ethylmaleimide and demonstrated saturation kinetics.
Abstract: The activity of a cystine transport system in lysosomes prepared from the leukocytes of patients with cystinosis was found to be deficient. In normal subjects, this system was resistant to N-ethylmaleimide and demonstrated saturation kinetics. Lysosomes from individuals heterozygous for cystinosis demonstrated a reduced maximum velocity for cystine egress from lysosomes. The rate of cystine escape from normal lysosomes was enhanced by adenosine triphosphate. The availability of normal and mutant lysosomes provides a means of investigating mechanisms of amino acid transport across lysosomal membranes.

305 citations

Journal ArticleDOI
TL;DR: It is concluded that isolated cystinotic lysosomes demonstrate a pronounced, selective defect in the exodus of cystine, but not of the other amino acids examined.

152 citations

Journal ArticleDOI
TL;DR: A “new” human enzyme deficiency state has thus been characterized and further studies of this disorder should permit clarification of the possible role of this transpepti-dase in human amino acid transport and in glutathione metabolism.

138 citations

Journal ArticleDOI
09 May 1986-Science
TL;DR: Normal fibroblasts exposed to N-acetylmannosamine yielded lysosome-rich granular fractions loaded with free (unbound) sialic acid, whose velocity of egress increased with increasing initial loading.
Abstract: Normal fibroblasts exposed to N-acetylmannosamine yielded lysosome-rich granular fractions loaded with free (unbound) sialic acid, whose velocity of egress increased with increasing initial loading. Fibroblast granular fractions of patients with Salla disease exhibited negligible egress of sialic acid, whether endogenous or derived from N-acetylmannosamine exposure. Salla disease represents the first disorder demonstrated to be caused by defective transport of a monosaccharide out of cellular lysosomes.

131 citations


Cited by
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Journal ArticleDOI
TL;DR: It is reported here that 2-vinylpyridine is a much better reagent for the derivitization of glutathione, and it is demonstrated that the total glutATHione concentration in mouse plasma is substantially higher than generally reported and that glutathion disulfide constitutes less than 30% of the totalglutathione present.

4,279 citations

Journal ArticleDOI
TL;DR: Results for GSH levels agreed well with earlier reports but levels of GSSG estimated here were higher than earlier reported values, and the reasons for the apparently higher levels ofGSSG are discussed.

3,881 citations

Book ChapterDOI
TL;DR: 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB)-GSSG reductase recycling assay for total glutathione is a specific, sensitive, rapid, and reliable procedure, however, because the method depends on an accurate standard curve, appropriate standards containing the protein precipitating agent are essential.
Abstract: Publisher Summary There are a number of procedures, for example, chemical, enzymatic, and chromatographic for the determination of glutathione (GSH) and glutathione disulfide (GSSG) in biological samples. Enzymatic and chromatographic methods for the determination of glutathione in biological samples are described in this chapter. Because GSH readily oxidizes nonenzymatically and because it is a good substrate of γ-glutamyl transpeptidase, the biological samples are acidified quickly to reduce oxidation of GSH to GSSG and to mixed disulfides, and to inactivate γ-glutamyl transpeptidase. Glutathione oxidizes rapidly at pH values greater than 7. Acid treatment inactivates γ-glutamyl transpeptidase, which catalyzes the reactions that decrease the levels of both GSH and GSSG. The optimum method for treating biological samples depends upon the tissue and the experimental system. The discussed 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB)-GSSG reductase recycling assay for total glutathione is a specific, sensitive, rapid, and reliable procedure. However, because the method depends on an accurate standard curve, appropriate standards containing the protein precipitating agent are essential.

2,623 citations

Journal ArticleDOI
01 Jan 1976-Planta
TL;DR: It is proposed that glutathione functions to stabilise enzymes of the Calvin cycle, and it may also act to keep ascorbic acid in chloroplasts in the reduced form.
Abstract: Both glutathione and an NADPH-dependent glutathione reductase are present in spinach (Spinacia oleracea L.) chloroplasts. It is proposed that glutathione functions to stabilise enzymes of the Calvin cycle, and it may also act to keep ascorbic acid in chloroplasts in the reduced form.

2,351 citations