Biomaterial Database

Effect of different antibiotics on efficiency of transformation of bacteria by electroporation. 1994

C Steele, and S Zhang, and E J Shillitoe

University of Texas Health Science Center, Houston.

We noted large differences in the transformation efficiency of Escherichia coli when different methods were used for transformation. To analyze these observations, the ampicillin and tetracycline resistance plasmid, pBR322, was transformed into HB101 and DH5 alpha E. coli using calcium chloride or electroporation, and the clones containing the plasmids were selected under various conditions. Electroporation yielded around 5 x 10(7) transformants per microgram of plasmid DNA when ampicillin was used for selection, but only 5 x 10(5) transformants per microgram when tetracycline was used. A calcium-chloride method of transformation showed no differences between the two antibiotics. The loss of efficiency of electroporation in the presence of tetracycline was also seen with three tetracycline-related antibiotics and could be blocked by chelating agents. It was also overcome by a 3-h preincubation of the bacteria before exposure to antibiotic. D-Cycloserine showed a selective effect on electroporated bacteria, but Polymyxin-B, chloramphenicol or phosphonomycin did not. The mechanism of inhibition by tetracycline-related antibiotics is not known, but the results show that the recovery of electroporated bacteria may be significantly decreased if these antibiotics are used.

UI	MeSH Term	Description	Entries
D002122	Calcium Chloride	A salt used to replenish calcium levels, as an acid-producing diuretic, and as an antidote for magnesium poisoning.	Calcium Chloride Dihydrate,Calcium Chloride, Anhydrous
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
D000667	Ampicillin	Semi-synthetic derivative of penicillin that functions as an orally active broad-spectrum antibiotic.	Penicillin, Aminobenzyl,Amcill,Aminobenzylpenicillin,Ampicillin Sodium,Ampicillin Trihydrate,Antibiotic KS-R1,Omnipen,Pentrexyl,Polycillin,Ukapen,Aminobenzyl Penicillin,Antibiotic KS R1,KS-R1, Antibiotic,Sodium, Ampicillin,Trihydrate, Ampicillin
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
D014169	Transformation, Bacterial	The heritable modification of the properties of a competent bacterium by naked DNA from another source. The uptake of naked DNA is a naturally occuring phenomenon in some bacteria. It is often used as a GENE TRANSFER TECHNIQUE.	Bacterial Transformation
D018274	Electroporation	A technique in which electric pulses, in kilovolts per centimeter and of microsecond-to-millisecond duration, cause a loss of the semipermeability of CELL MEMBRANES, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA. Depending on the dosage, the formation of openings in the cell membranes caused by the electric pulses may or may not be reversible.	Electric Field-Mediated Cell Permeabilization,Irreversible Electroporation,Reversible Electroporation,Electropermeabilisation,Electric Field Mediated Cell Permeabilization,Electroporation, Irreversible,Electroporation, Reversible