Biomaterial Database

Excision repair of ultraviolet-irradiated deoxyribonucleic acid in plasmolyzed cells of Escherichia coli. 1976

E Seeberg, and P Strike

A system of cells made permeable by treatment with high concentrations of surcrose (plasmolysis) has been exploited to study the excision repair of ultraviolet-irradiated deoxyribonucleic acid in Escherichia coli. It is demonstrated that adenosine 5'-triphosphate is required for incision breaks to be made in the bacterial chromosome as well as in covalently closed bacteriophage lambda deoxyribonucleic acid. After plasmolysis, uvrC mutant strains appear as defective in the incision step as the uvrA-mutated strains. This is in contrast to the situation in intact cells where uvrC mutants accumulate single-strand breaks during postirradiation incubation. These observations have led to the proposal of a model for excision repair, in which the ultraviolet-specific endonuclease, coded for by the uvrA and uvrB genes, exists in a complex with the uvrC gene product. The complex is responsible for the incision and possibly also the excision steps of repair. The dark-repair inhibitors acriflavine and caffeine are both shown to interfere with the action of the adenosine 5'-triphosphate-dependent enzyme.

UI	MeSH Term	Description	Entries
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D009995	Osmosis	Tendency of fluids (e.g., water) to move from the less concentrated to the more concentrated side of a semipermeable membrane.	Osmoses
D011830	Radiation Effects	The effects of ionizing and nonionizing radiation upon living organisms, organs and tissues, and their constituents, and upon physiologic processes. It includes the effect of irradiation on food, drugs, and chemicals.	Effects, Radiation,Effect, Radiation,Radiation Effect
D002110	Caffeine	A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.	1,3,7-Trimethylxanthine,Caffedrine,Coffeinum N,Coffeinum Purrum,Dexitac,Durvitan,No Doz,Percoffedrinol N,Percutaféine,Quick-Pep,Vivarin,Quick Pep,QuickPep
D002463	Cell Membrane Permeability	A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.	Permeability, Cell Membrane
D004260	DNA Repair	The removal of DNA LESIONS and/or restoration of intact DNA strands without BASE PAIR MISMATCHES, intrastrand or interstrand crosslinks, or discontinuities in the DNA sugar-phosphate backbones.	DNA Damage Response
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D004279	DNA, Viral	Deoxyribonucleic acid that makes up the genetic material of viruses.	Viral DNA
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
D000167	Acriflavine	3,6-Diamino-10-methylacridinium chloride mixt. with 3,6-acridinediamine. Fluorescent dye used as a local antiseptic and also as a biological stain. It intercalates into nucleic acids thereby inhibiting bacterial and viral replication.	Xanthacridinum,2,8-Diamino-10-Methylacridinium Chloride Mixture With 2,8-Diaminoacridine