Holger Kramer

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Dependence of the lumiflavin triplet-triplet absorption spectrum on pH. Figure I shows the transient change in absorption when lumiflavin soJutions of pH = 2, pH = 7, and pH = 13 are flashed. From this the triplet-triplet absorption spectra of the acid (pH = 2), neutral (pH = 7), 1964; Kramer and Maute, 1972). The flash energy could be varied between 300 J(More)
NFAT-dependent gene expression is essential for the development and function of the nervous, immune, and cardiovascular systems and kidney, bone, and skeletal muscle. Most NFAT protein resides in the cytoplasm because of extensive phosphorylation, which masks a nuclear localization sequence. Dephosphorylation by the Ca(2+)-calmodulin-activated protein(More)
The major coat protein of native filamentous phage fd is vulnerable to digestion by subtilisin, but not by any of a number of other proteolytic enzymes. Degradation by the non-specific protease subtilisin occurs at specific sites in the N-terminal portion of g8p. The N-terminal part of the protein is considered to be the outer layer of a two-layered coat.(More)
The adsorption complex of filamentous phage fd consists of two minor coat proteins, g3p and g6p, and is considered to be not only a structural entity, but also a functional unit to terminate phage assembly. Cells were infected with phage M13am8H1, which cannot assemble because it lacks the major coat protein g8p, although producing all of the other minor(More)
Evidence is given for the fact that the excited flavin triplet (3Flox) exhibits competitive 1e- and 2e- transfer chemistry, depending on the nature of the photosubstrate. As an 'external' photo-reductant, the 2e- donor borohydride has been investigated. Borohydride is found to compete effectively with the 'internal' 1e- donors, namely excess starting flavin(More)
The mechanism of flavin photoreduction by the amino acids, EDTA, and nitrilotriacetate is shown to be due to light-induced charge separation, which is irreversible in the dark. The irreversibility originates from the decarboxylation of the amino acid radical. This fast process changes the redox properties of the radical and makes a further donation of an(More)
In order to gain more insight into flavin radicals, on which the selection of 1e-, and 2e- -oxireduction modes in flavoproteins depends, we have investigated structure, spectral properties and decay mode of molecular species occurring in the half-reduced 5-deazaflavin "model" system by flash photolysis and pulse radiolysis. (1) Enforced 1e- -reduction of(More)