Biomaterial Database

Selective assimilation of selenite by Escherichia coli. 1982

T A Brown, and A Shrift

The assimilation of selenite by Escherichia coli involves a transport process specific for this anion. Cystine, a repressor of sulfate and selenite uptake, when added to the growth medium, had no effect on selenite uptake; nor did sulfite inhibit assimilation of selenite. Cells grown aerobically in a basic salts medium transported selenite at an initial rate of 0.14 mumol . g-1 min-1 and a Vmax of 393.0 mumol. g-1 . min-1. In contrast, cells grown in a medium that contained the trace elements necessary for synthesis of the selenoenzyme formate dehydrogenase took up selenite at a significantly faster rate (initial rate = 0.27 mumol . g-1 . min-1, Vmax = 658.2 mumol . g-1 . min-1). Km values for the transport process in the two media, however, were found to be similar. The results suggest the existence of a metabolic pathway, specific for selenite, responsible for the incorporation of selenium into formate dehydrogenase.U

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D003553	Cystine	A covalently linked dimeric nonessential amino acid formed by the oxidation of CYSTEINE. Two molecules of cysteine are joined together by a disulfide bridge to form cystine.	Copper Cystinate,L-Cystine,L Cystine
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic
D012643	Selenium	An element with the atomic symbol Se, atomic number 34, and atomic weight 78.97. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.	Selenium-80,Selenium 80
D013431	Sulfates	Inorganic salts of sulfuric acid.	Sulfate,Sulfates, Inorganic,Inorganic Sulfates
D013447	Sulfites	Inorganic salts of sulfurous acid.	Sulfite,Sulfites, Inorganic,Inorganic Sulfites
D013691	Tellurium	An element that is a member of the chalcogen family. It has the atomic symbol Te, atomic number 52, and atomic weight 127.60. It has been used as a coloring agent and in the manufacture of electrical equipment. Exposure may cause nausea, vomiting, and CNS depression.
D013885	Thiosulfates	Inorganic salts of thiosulfuric acid possessing the general formula R2S2O3.	Thiosulfate
D020887	Selenious Acid	A selenium compound with the molecular formula H2SO3. It used as a source of SELENIUM, especially for patients that develop selenium deficiency following prolonged PARENTERAL NUTRITION.	Selenite,Selenous Acid,Acid, Selenious,Acid, Selenous