Biomaterial Database

Tetracycline uptake by susceptible Escherichia coli cells. 1985

M Argast, and C F Beck

Experiments measuring the initial uptake of commercial (3H) tetracycline exhibit two distinct kinetic phases: a rapid phase followed by a slow phase. (3H) tetracycline purified by chromatography on a Dowex 50WX2 column exhibited only monophasic rapid uptake when tested with susceptible Escherichia coli cells. Cyanide inhibited the uptake of purified (3H) tetracycline only partially while transport of proline and maltose was entirely abolished. Energy independent accumulation of tetracycline may be accounted for by binding to cellular constituents. Uptake of tetracycline--as measured by inhibition of beta-galactosidase synthesis--was strongly affected by a shift in temperature from 37 degrees C to 21 degrees C while carrier-mediated transport systems revealed only minor reductions. Taken together with the non-saturability of tetracycline uptake and the evidence for diffusion of tetracycline through phospholipid bilayers [Argast and Beck (1984) Antimicrob Agents Chemother 26:263-265] these data support the hypothesis that tetracycline enters the cytoplasm by diffusion.

UI	MeSH Term	Description	Entries
D003486	Cyanides	Inorganic salts of HYDROGEN CYANIDE containing the -CN radical. The concept also includes isocyanides. It is distinguished from NITRILES, which denotes organic compounds containing the -CN radical.	Cyanide,Isocyanide,Isocyanides
D003593	Cytoplasm	The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)	Protoplasm,Cytoplasms,Protoplasms
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
D001616	beta-Galactosidase	A group of enzymes that catalyzes the hydrolysis of terminal, non-reducing beta-D-galactose residues in beta-galactosides. Deficiency of beta-Galactosidase A1 may cause GANGLIOSIDOSIS, GM1.	Lactases,Dairyaid,Lactaid,Lactogest,Lactrase,beta-D-Galactosidase,beta-Galactosidase A1,beta-Galactosidase A2,beta-Galactosidase A3,beta-Galactosidases,lac Z Protein,Protein, lac Z,beta D Galactosidase,beta Galactosidase,beta Galactosidase A1,beta Galactosidase A2,beta Galactosidase A3,beta Galactosidases
D013752	Tetracycline	A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.	4-Epitetracycline,Achromycin,Achromycin V,Hostacyclin,Sustamycin,Tetrabid,Tetracycline Hydrochloride,Tetracycline Monohydrochloride,Topicycline,4 Epitetracycline