Subject(s)
Living Wills , Physicians , Ethics, Medical , Humans , Persistent Vegetative State , Physician-Patient Relations , United StatesABSTRACT
A chemically defined medium for Rothia dentocariosa has been established. All strains tested, including the type strain, grew well in this medium. Rothia strains had a generation time of 3.5 to 4.0 h, with a yield of 62 mg (dry weight) per 100 ml after 72 h of growth in the chemically defined medium.
Subject(s)
Actinomycetaceae/growth & development , Culture MediaABSTRACT
Hexadecanoate was translocated in Nocardia asteroides by a constitutive transport system(s), which transported short, medium, and long-chain fatty acids. Inhibition of hexadenocanoate transport by homologues suggested that at least two systems are present: one specific for short-chain fatty acids and the other specific for medium- and long-chain fatty acids. Saturation kinetics typical of a carrier-mediated transport system (Kt = 870 muM)were observed, and concentration of fatty acids against a gradient was achieved. Inhibitor studies indicated that free sulfhydryl groups, a functional respiratory chain, and energy are required for translocation. Efflux of [14C]hexadecanoate in the presence of excess unlabeled hexadecanoate or 2,4-dinitrophenol and the cytoplasmic localization of acyl-coenzyme A synthetase (acid:coenzyme A ligase [adenosine monophosphate]; EC 6.2.1.3) (Calmes and Deal, 1973) are consistent with the hypothesis that fatty acids are transported and released intracellularly as free fatty acids.
Subject(s)
Fatty Acids/metabolism , Nocardia asteroides/metabolism , Adsorption , Biological Transport, Active , Cell Membrane/metabolism , Coenzyme A Ligases/metabolism , Kinetics , Nocardia asteroides/enzymology , Palmitates/metabolism , Sulfhydryl Reagents/pharmacology , Uncoupling Agents/pharmacologySubject(s)
Nocardia asteroides/ultrastructure , Polysaccharides, Bacterial/analysis , Chromatography, Thin Layer , Cytoplasmic Granules/analysis , Glucosyltransferases , Glycogen/analysis , Inclusion Bodies/analysis , Iodine , Microscopy, Electron , Molecular Conformation , Nocardia asteroides/analysis , SpectrophotometryABSTRACT
Cell-free extracts of Nocardia asteroides activated saturated fatty acids from octanoate to octadecanoate, plus docosanoate; maximal activation occurred with dodecanoate. No activation of short-chain fatty acids was observed. The activating enzyme, characterized as an acyl-coenzyme A (Co A) synthetase (acid: Co A ligase [adenosine monophosphate]; EC 6.2.1.3), was localized in the cytoplasm of the cells and had absolute requirements for Co A, adenosine 5'-triphosphate, and Mg(2+). Kinetic data suggested that N. asteroides possessed at least two synthetases: one specific for short-chain fatty acids, and the other specific for medium- and long-chain fatty acids.
