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Showing papers by "Alexander N. Glazer published in 1988"


Journal ArticleDOI
TL;DR: The major bilin peptides arising from in vitro adduct formation at each of these sites differed both in chromatographic behavior and in spectroscopic properties from the corresponding PCB peptides isolated from tryptic digests of native C-phycocyanin.

103 citations


Journal ArticleDOI
TL;DR: Examination of the major components of human urine in this assay confirms that at physiological concentrations, urate protects against both types of oxygen radicals, and a novel finding is that creatinine protects efficiently by a chelation mechanism against radical damage in the ascorbate‐Cu2+ system at Creatinine, ascorBate, and Cu2+ concentrations comparable to those in normal urine.
Abstract: Attack by reactive oxygen species leads to a decay in phycoerythrin fluorescence emission. This phenomenon provides a versatile new assay for small molecules and macromolecules that can function as protective compounds. With 1-2 x 10(-8) M phycoerythrin, under conditions where peroxyl radical generation is rate-limiting, the fluorescence decay follows apparent zero-order kinetics. On reaction with HO., generated with the ascorbate-Cu2+ system, the fluorescence decays with apparent first-order kinetics. Examination of the major components of human urine in this assay confirms that at physiological concentrations, urate protects against both types of oxygen radicals. A novel finding is that creatinine protects efficiently by a chelation mechanism against radical damage in the ascorbate-Cu2+ system at creatinine, ascorbate, and Cu2+ concentrations comparable to those in normal urine. Urate and creatinine provide complementary modes of protection against reactive oxygen species in the urinary tract.

83 citations


Journal ArticleDOI
TL;DR: The results show that the major bilin products arising from the reaction of PCB with apophycocyanin differ from the bilins present in C-phycOCyanin.

82 citations


Journal ArticleDOI
TL;DR: Results show that the spontaneous in vitro addition of bilins to apophycocyanin does not exhibit the site selectivity of bilin addition observed in vivo, which offers the opportunity to form novel semisynthetic phycobiliproteins.

56 citations


Journal ArticleDOI
TL;DR: The cyanobacterial photosystem, I complex from Synechococcus sp. PCC6301 contains polypeptides of apparent Mr of 70,000, 18, 000, 17,700, 16,000 and 10,000 as mentioned in this paper.
Abstract: The cyanobacterial photosystem, I complex from Synechococcus sp. PCC6301 contains polypeptides of apparent Mr of 70,000, 18,000, 17,700, 16,000 and 10,000. Procedures were developed for the purification of the Mr 17,700 and 10,000 polypeptides. Amino acid analyses showed the absence of cystine and cysteine from these polypeptides. Amino-terminal sequences of 98 residues for the Mr 17,700 polypeptide and of 42 residues for the Mr 10,000 polypeptide were determined. Studies of pigment distribution within the photosystem I complex indicated that the binding of chlorophyll a and β-carotene is in part dependent on the presence of these polypeptides.

20 citations