Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several flavoproteins and cytochromes that occur as major components in extracts of the yellow bioluminescence Y1 strain of the marine bacterium Vibrio fischeri have been purified and characterized with respect to their mass (SDS/PAGE and matrix-assisted laser-desorption/ionization MS), chromatographic properties, N-terminal sequence, and spectroscopy (absorption, fluorescence emission and anisotropy decay). The investigated proteins were as follows: yellow fluorescence protein (YFP) with bound riboflavin, FMN or 6,7-dimethyl-8-ribityllumazine; a blue fluorescence protein (BFP) with bound 6,7-dimethyl-8-ribityllumazine, riboflavin, or 6-methyl-7-oxo-8-ribityllumazine; thioredoxin reductase with FAD as ligand; and two c-type diheme cytochromes, c551 and c554. We present evidence that the riboflavin-bound YFP has an N-terminal sequence corresponding to that published for the dimeric YFP. We show that an equilibrium replacement of the riboflavin can be made with excess lumazine derivative and that lumazine-bound YFP has different bioluminescence properties to those of the lumazine protein from Photobacterium leiognathi. BFP is a different protein again, and in the bacterial lysate it occurs in multiple forms, ligated to either riboflavin, lumazine, or the 7-oxolumazine derivative. The N-terminal sequence for BFP shows similarities to those of the YFP proteins and to lumazine protein and riboflavin synthase from Photobacterium. BFP in any form has no bioluminescence or riboflavin-synthase activity. A 70-kDa fluorescent flavoprotein with FAD as ligand has an N-terminal sequence highly similar to those of thioredoxin reductases from Haemophilus influenzae and Escherichia coli. Cytochrome contaminations in previous preparations of YFP have been removed and are identified as the two c-type cytochromes c551 and c554. Both inhibit the NADH-induced bioluminescence in the reductase/luciferase system with the luciferases from P. leiognathi and V. fischeri. The N-terminal amino acid sequence of the cytochrome (c551) corresponds to a diheme cytochrome c4. The spectral properties of c554 are similar to those of other c5 cytochromes, and both c554 and c551 have absorption spectra similar to those of the respective cytochromes from the gram-negative bacteria Pseudomonas and Azotobacter.
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PMID:Purification and characterization of flavoproteins and cytochromes from the yellow bioluminescence marine bacterium Vibrio fischeri strain Y1. 918 20

White, D. C. (Rockefeller Institute, New York, N.Y.). Respiratory systems in hemin-requiring Haemophilus species. J. Bacteriol. 85:84-96. 1963.-If grown in Levinthal's medium or in proteose peptone medium with excess hemin, Haemophilus influenzae, H. aegyptius, and H. canis (H. haemoglobinophilus) form an electron-transport system consisting of six cytochromes and two respiratory flavoproteins. In proteose peptone, these species can greatly modify the composition of their electron-transport complex. With anaerobic incubation in the presence of nitrate, they produce increased amounts of cytochrome c(1) and the cytochrome oxidases a(1) and o. This anaerobic pattern is greatly exaggerated by growth under carbon monoxide, in which case large concentrations of cytochrome oxidase are produced. In the presence of the inhibitor secobarbital or of growth-limiting amounts of hemin, intermediate amounts of cytochromes and respiratory flavoproteins are formed. When only small amounts of hemin are present, these species grow but form no detectable cytochrome system. Catalase is the only hemoprotein found. Under these conditions, the addition of glucose induces the formation of a lactate oxidase flavoprotein if the system is incubated aerobically. This cytochromeless state also occurs when these species are grown in KCN or anaerobically without nitrate and with excess hemin. The ability of these species to modify the composition of the electron-transport system strongly suggests that this function unit is formed from individual components. Hemin-requiring Haemophilus species have a hemin-sparing compensatory mechanism that allows growth under conditions under which hemin-independent Haemophilus species will not grow.
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PMID:Respiratory systems in the hemin-requiring Haemophilus species. 1400 Feb 93

White, David C. (University of Kentucky College of Medicine, Lexington). Synthesis of 2-demethyl vitamin K(2) and the cytochrome system in Haemophilus. J. Bacteriol. 89:299-305. 1965.-The synthesis of the respiratory quinone, 2-demethyl vitamin K(2), is stimulated in Haemophilus parainfluenzae under conditions which provoke the synthesis of the cytochrome system. However, the various components of the electron-transport system can be formed in different proportions. The primary flavoprotein dehydrogenases are readily dissociated from the membrane without affecting the content of membrane-bound quinone, cytochrome b(1), or the cytochrome oxidases. These dehydrogenases must be membrane-bound to function, and each can be formed at a different rate. Molar ratios of various constituents of the electron-transport chain were calculated by use of reasonable extinction coefficients for the cytochromes. The molar ratio of quinone to cytochrome c(1) goes from 40 to 3 as the quinone content increases eightfold during the growth cycle. Similarly, the molar ratio of quinone to cytochrome oxidase a(2) varies from 27 to 17, and then increases to 31 as cytochrome oxidase a(1) assumes the oxidase function. The molar ratio of quinone to cytochrome b(1) remains 14 to 1 over a sixfold increase in both components measured in a mutant where cytochrome c(1) does not obscure cytochrome b(1). A similar consistency was noted between the quinone and cytochrome b(1) formation in the hemin-requiring H. influenzae.
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PMID:SYNTHESIS OF 2-DEMETHYL VITAMIN K2 AND THE CYTOCHROME SYSTEM IN HAEMOPHILUS. 1425 94