Biomaterial Database

Relation between Escherichia coli endonucleases specific for apurinic sites in DNA and exonuclease III. 1977

S Ljungquist, and T Lindahl

Contradictory data have recently been published from two different laboratories on the presence vs absence of an intrinsic endonucliolytic activity of E. coli exonuclease III at apurinic sites in double-stranded DNA. It is shown here that an endonuclease activity of this specificity co-chromatographs exactly with exonuclease III on phosphocellulose and Sephadex G-75 columns, indicating that the endonuclease and exonuclease activities are due to the same enzyme. In addition, another E. coli endonuclease specific for apurinic sites exists, which can be separated from exonuclease III by the same chromatographic procedures.

UI	MeSH Term	Description	Entries
D011119	Polynucleotides	BIOPOLYMERS composed of NUCLEOTIDES covalently bonded in a chain. The most common examples are DNA and RNA chains.	Polynucleotide
D003851	Deoxyribonucleases	Enzymes which catalyze the hydrolases of ester bonds within DNA. EC 3.1.-.	DNAase,DNase,Deoxyribonuclease,Desoxyribonuclease,Desoxyribonucleases,Nucleases, DNA,Acid DNase,Alkaline DNase,DNA Nucleases,DNase, Acid,DNase, Alkaline
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D004720	Endonucleases	Enzymes that catalyze the hydrolysis of the internal bonds and thereby the formation of polynucleotides or oligonucleotides from ribo- or deoxyribonucleotide chains. EC 3.1.-.	Endonuclease
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
D005092	Exonucleases	Enzymes that catalyze the release of mononucleotides by the hydrolysis of the terminal bond of deoxyribonucleotide or ribonucleotide chains.	Exonuclease,3'-5'-Exonuclease,3'-5'-Exonucleases,5'-3'-Exonuclease,5'-3'-Exonucleases,3' 5' Exonuclease,3' 5' Exonucleases,5' 3' Exonuclease,5' 3' Exonucleases
D001080	Apurinic Acid	Hydrolysate of DNA in which purine bases have been removed.	Acid, Apurinic
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities