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Glutamate uptake in Thiobacillus novellus.

D J Hoban·R M Lyric
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Abstract

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.

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Aspartic AcidBiological Transport, ActiveCyanidesDicyclohexylcarbodiimideFluoridesGlutamatesKineticsNitratesTemperatureThiobacillusUncoupling AgentsJournal Article

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D J Hoban, R M Lyric. 1977. Glutamate uptake in Thiobacillus novellus.. https://doi.org/10.1139/m77-040

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