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R M Lyric

Publications and source records attributed to R M Lyric.

7 recordsLinked to original sources
PubMed1977

Glutamate uptake in Thiobacillus novellus.

Properties of the glutamate uptake system of Thiobacillus novellus were investigated using intact cells. Two kinetically distiguishable components were found and designated at the high-affinity (HA) component with an apparent Km of 33 micronM, and the low-affinity (LA) component with a Km of 18 mM. Glutamate accumulation was temperature-sensitive and could be inhibited by the addition of wide range of inhibitors including cyanide, dinitrophenol (DNP), iodoacetate, mercuric chloride, sodium azide, carbonyl cyanide m-chlorophenyl hydrazone (CCCP), and dicyclhexylcarbodiimide (DCCD). The complex kinetics of the uptake process may be due to the rapid incorporation of added glutamate into a small peptide. This soluble peptide was formed rapidly after glutamate addition, and accumulated in whole cells.

Aspartic Acid↗
PubMed1975

Phosphoenolpyruvate carboxylase of Thiobacillus thioparus. I. General properties.

Phosphoenolpyruvate (PEP) carboxylase (orthophosphate:oxalacetate carboxylase (phosphorylating), EC 4.1.1.31) was purified 19-fold from the obligate chemoautotroph, Thiobacillus thioparus. Michaelis constants for the substrates were found to be 0.44 mM for phosphoenolpyruvate, 0.89 mM for bicarbonate, and 0.37 mM for magnesium, using Tris-HC1, pH 7.3. 1-Aspartate, 1-malate, and orthophosphate were found to be inhibitors of enzyme activity, while acetyl CoA, FDP, GTP, and CDP had no effect. Dioxane greatly stimulated enzyme activity.

Aspartic Acid↗
PubMed1973

Isolation and characterization of a bacteriophage for Thiobacillus novellus.

A DNA-containing bacteriophage for Thiobacillus novellus has been isolated from sewage and purified by ammonium sulfate precipitation, differential centrifugation, and cesium chloride equilibrium centrifugation. The buoyant density of this phage in CsCl is 1.51 g/cm(3). Electron microscopy studies have revealed a polyhedral head about 60 nm in diameter and a tail surrounded by a number of fine filaments. It has an adsorption rate constant of 1.1 x 10(-9) ml/min, a latent period of 45 min, and an average burst size of 150. The mole guanine and cytosine content in its DNA has been estimated to be 57 to 58%. Five structural proteins with molecular weights of 62,000, 42,500, 30,500, 17,750, and 13,500 have been detected by polyacrylamide gel electrophoresis techniques.

Adsorption↗