Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:6.5.1.2 (DNA ligase)
 2,749 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The poly(dA) dependent T4 polynucleotide ligase catalyzed polymerization of oligodeoxythymidylates is dependent upon duplex stability. The antibiotics ethidium bromide, netropsin and Hoechst 33258 stabilize the duplex poly(dA) . P(dT)n (n = 6-10) to thermal denaturation. Ethidium bromide to DNA ratio of 1.25 and netropsin or Hoechst 33258 to DNA ratio of 0.1 the Tm of d(pT) 10 . poly (dA) was increased by 10 degrees and 25 degrees C respectively. The T4 polynucleotide ligase activity was not inhibited under these conditions and temperature optimum of joining of d(pT) 10 . poly(dA) was increased 5 degrees to 10 degrees by the binding of the antibiotics. Duplexes containing shorter oligodeoxythymidylates required lower concentrations of the antibiotics netropsin or Hoechst 33258 to show no inhibition of T4 polynucleotide ligase. The temperature optima of joining the duplexes d(pT)6 . POLY(DA) and d(pT) 8 . poly(dA) were increased by 5 degrees C upon binding of the antibiotics. Polyacrylamide gel analysis of the T4 polynucleotide ligase catalyzed joining of the oligodeoxythymidylates showed that the presence of antibiotics affected the product distribution of the polymerized oligomers.
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PMID:The effect of antibiotics on the T4 polynucleotide ligase catalyzed template dependent polymerization of oligodeoxythymidylates. 45 Jul 17

The self-complementary octanucleotide dT-A-G-T-A-C-T-A has been synthesized and its sequence confirmed by two-dimensional fingerprinting. Under conditions used for the T4 polynucleotide ligase reaction, this oligonucleotide forms a dimeric duplex which shows a Tm of 18 degrees C. The optimal rate of joining of the 32P-labeled duplex occurs between 12 and 15 degrees C. The rate is highly concentration dependent, as expected for a bimolecular process. Polyacrylamide gel electrophoretic analysis of this reaction shows the presence of products up to 120 nucleotides in length. In a denaturing gel, each product appears as a double band due to the presence of its 5'-adenylylated activated intermediate. Substrates larger than eight base pairs are utilized more rapidly than the eight base pair duplex, indicating that the T4 ligase has a higher affinity for longer substrates. The low level of nicked intermediates suggests that the joining of both strands requires two steps, the rates of which must be similar.
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PMID:T4 polynucleotide ligase catalyzed joining of short synthetic DNA duplexes at base-paired ends. 62 41