Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our recent findings suggest that enzymatic hydrolysis of the intradimer phosphodiester bond may constitute the initial step in the repair of UV light-induced cyclobutane pyrimidine dimers in human cells. To examine the susceptibility of this phosphodiester linkage to enzyme-mediated hydrolysis, the trinucleotide d-Tp-TpT was UV-irradiated and the two isomeric compounds containing a cis-syn-cyclobutane dimer were isolated by high performance liquid chromatography and treated with various deoxyribonucleases. Snake venom phosphodiesterase hydrolyzed only the 3'-phosphodiester group in the 5'-isomer (d-T less than p greater than TpT) but was totally inactive toward the 3'-isomer (d-TpT less than p greater than T). In contrast, calf spleen phosphodiesterase only operated on the 3'-isomer by cleaving the 5'-internucleotide bond. Kinetic analysis revealed that (i) the activity of snake venom phosphodiesterase was unaffected by a dimer 5' to a phosphodiester linkage, (ii) the action of calf spleen phosphodiesterase was partially inhibited by a dimer 3' to a phosphodiester bond, and (iii) Escherichia coli phr B-encoded DNA photolyase reacted twice as fast with d-T less than p greater than TpT as with d-TpT less than p greater than T. Mung bean nuclease, nuclease S1, and nuclease P1 all cleaved the 5'-internucleotide linkage, but not the intradimer phosphodiester bond, in d-TpT less than p greater than T. Both phosphate groups in d-T less than p greater than TpT were refractory to mung bean nuclease or nuclease S1. Incubation of d-T less than p greater than TpT with nuclease P1, however, generated the novel compound dT less than greater than d-pTpT containing a severed intradimer phosphodiester linkage. Accordingly, nuclease P1 represents the first purified enzyme known to hydrolyze an intradimer phosphodiester linkage.
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PMID:Enzymatic analysis of isomeric trithymidylates containing ultraviolet light-induced cyclobutane pyrimidine dimers. I. Nuclease P1-mediated hydrolysis of the intradimer phosphodiester linkage. 253 79

Partial depurination of d-ApA produced two UV260nm-absorbing isomers, d-SpA and d-ApS (where S represents the depurinated deoxyribose sugar), that provided simple model compounds with which to examine, by HPLC, the response of nucleases to phosphodiester bonds flanked 3' or 5' by an apurinic site. The structural identity of each compound was established by (i) reaction with methoxyamine to confirm the presence of an abasic deoxyribose group, and (ii) degradation of d-SpA under mild alkaline conditions to distinguish it from d-ApS. At an enzyme concentration which led to complete hydrolysis of d-ApA, snake venom phosphodiesterase readily cleaved d-SpA to 5'-dAMP but had no discernible effect on d-ApS. Calf spleen phosphodiesterase also failed to act on one isomer, in this instance d-SpA, but additionally reacted at a much slower rate (approximately 100 fold) with d-ApS than with d-ApA. Three single-strand specific endonucleases, nuclease P1, nuclease S1 and mung bean nuclease, all responded in an identical manner, hydrolysing d-ApS but not d-SpA. The possibility that the aldehyde group at the AP sites might be responsible for some of these observations was rejected after repeating the enzyme digestions with the methoxyamine-capped molecules and observing no differences from the reactions with d-SpA and d-ApS.
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PMID:Selective hydrolysis by exo- and endonucleases of phosphodiester bonds adjacent to an apurinic site. 254 53

This paper describes for the first time the synthesis of alpha-oligonucleotides containing the four usual bases. Two unnatural hexadeoxyribonucleotides: alpha-[d(CpApTpGpCpG)] and alpha-[d(CpGpCpApTpG)], consisting only of alpha-anomeric nucleotide units, were obtained by an improved phosphotriester method, in solution. Starting material was the four base-protected alpha-deoxyribonucleosides 3a-d. Pyrimidine alpha-deoxynucleosides 3a and 3b were prepared by self-anomerization reactions followed by selective deprotection of sugar hydroxyles, while the two purine alpha-deoxynucleosides 3c and 3d were prepared by glycosylation reactions. In the case of guanine alpha-nucleoside derivative a supplementary base-protecting group: N,N-diphenylcarbamoyl was introduced on O6-position in order to avoid side-reactions during oligonucleotide assembling. The hexadeoxynucleotide alpha-[d(CpApTpGpCpG)] was tested as substrate of selected endo- and exonucleases. In conditions where the natural corresponding beta-hexamer was completely degradated by nuclease S1 and calf spleen phosphodiesterase, the alpha-oligonucleotide remained almost intact.
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PMID:alpha-DNA II. Synthesis of unnatural alpha-anomeric oligodeoxyribonucleotides containing the four usual bases and study of their substrate activities for nucleases. 357 96

Ribonuclease T2, nuclease S1, and snake venom phosphodiesterase were used as a structural probe for investigation of the interaction between Escherichia coli tRNAfMet and methionyl-tRNA synthetase, and the cleavage sites were analyzed by a rapid sequencing gel electrophoresis of 5'-32P-labeled tRNA. Both endonucleases cleaved the D-loop of synthetase-bound tRNA much more extensively than that of the free tRNA. Positions of A14, G15, A22, and G23 in the D-loop and C35 in the anticodon of the synthetase-bound tRNA were more susceptible to RNase T2. The synthetase-bound tRNA was predominantly cleaved by nuclease S1 at position of G15, G19, G20, and G23 in the D-loop and G2 in the acceptor stem. In contrast, the synthetase-bound tRNA was more resistant to the 3'-exonuclease, snake venom phosphodiesterase, than was the free tRNA molecule. These results suggest conformational change of the tRNA by the synthetase binding which weakened tertiary interaction between the D-loop and T psi C-loop/extra-loop. Production of acid-soluble radioactivity was also examined in the limited digestion of 5'-32P-labeled tRNA or 3'-14C-labeled methionyl-tRNA. The synthetase enhanced the release of acid-soluble oligonucleotides from the 5'-end of the tRNA but suppressed that from the 3'-end of the molecule. These results are consistent with that obtained by gel electrophoresis.
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PMID:Methionyl-tRNA synthetase-induced conformational change of Escherichia coli tRNAfMet. 626 70

The synthesis of oligodeoxynucleotides (ODNs) containing 5-[N-[2-[N,N-bis(2-aminoethyl)amino]ethyl]-carbamoyl]-2'-deoxyuridine (BAE) and 5-[N-[3-[N,N-bis(3-aminopropyl)amino]propyl]carbamoyl]-2'- deoxyuridine (BAP) is described. The thermal stabilities of duplexes containing these ODNs and either the complementary DNA or RNA strand and of triplexes consisting of these ODNs and the target duplex were studied by thermal denaturation. ODNs containing BAE or BAP stabilize duplex formation with either the complementary DNA or RNA strands but destabilize triplex formation with the target duplex. Furthermore, the resistance of these ODNs to nuclease hydrolysis was studied by using snake venom phosphodiesterase (a 3'-exonuclease) and nuclease S1 (an endonuclease). It was found that ODNs containing either BAE or BAP were more resistant to nucleolytic hydrolysis by either of the nucleases than the unmodified ODN.
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PMID:Nucleosides and nucleotides. 170. Synthesis and properties of oligodeoxynucleotides containing 5-[N-[2-[N,N-bis(2-aminoethyl)- amino]ethyl]carbamoyl]-2'-deoxyuridine and 5-[N-[3-[N,N-bis(3-aminopropyl) amino]propyl]carbamoyl]-2'-deoxyuridine. 946 May 44

To construct the nuclease-resistant oligodeoxynucleotides (ODNs) with natural phosphodiester linkages, we synthesized ODNs that contain 6'alpha-[N-(aminoalkyl)carbamoyloxy]-carbocyclic-thymidines (4, 5, and 6). The stability of these ODNs to nuclease hydrolysis was examined by using snake venom phosphodiesterase (3'-exonuclease) and nuclease S1 (endonuclease). It was found that the ODNs containing 4, 5, or 6 were more resistant to both the enzymes than the unmodified ODN. These nuclease-resistant properties are noteworthy, since they have natural phosphodiester linkages. Next, the thermal stabilities of duplexes consisting of these ODNs and either the complementary DNA or RNA were studied by thermal denaturation. The ODNs that contain 4 were found to enhance the thermal stability of the duplexes with the complementary DNA, while those containing 5 or 6 decreased the thermal stability of the ODN-DNA duplexes. On the other hand, all ODNs that contained 4, 5, or 6 decreased the thermal stability of the ODN-RNA duplexes.
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PMID:Nucleosides and nucleotides. 204. Synthesis of oligodeoxynucleotides containing 6'alpha-[N-(Aminoalkyl)carbamoyloxy]-carbocyclic-thymidines and the thermal stability of the duplexes and their nuclease-resistance properties. 1108 44

We report herein the synthesis and physical and physiological characterization of fully modified 2'-modified-4'-thioRNAs, i.e. 2'-fluoro-4'-thioRNA (F-SRNA) and 2'-O-Me-4'-thioRNA (Me-SRNA), which can be considered as a hybrid chemical modification based on 2'-modified oligonucleotides (ONs) and 4'-thioRNA (SRNA). In its hybridization with a complementary RNA, F-SRNA (15mer) showed the highest T(m) value (+16 degrees C relative to the natural RNA duplex). In addition, both F-SRNA and Me-SRNA preferred RNA as a complementary partner rather than DNA in duplex formation. The results of a comprehensive comparison of nuclease stability of single-stranded F-SRNA and Me-SRNA along with 2'-fluoroRNA (FRNA), 2'-O-MeRNA (MeRNA), SRNA, and natural RNA and DNA, revealed that Me-SRNA had the highest stability with t(1/2) values of > 24 h against S1 nuclease (an endonuclease) and 79.2 min against SVPD (a 3'-exonuclease). Moreover, the stability of Me-SRNA was significantly improved in 50% human plasma (t(1/2) = 1631 min) compared with FRNA (t(1/2) = 53.2 min) and MeRNA (t(1/2) = 187 min), whose modifications are currently used as components of therapeutic aptamers. The results presented in this article will, it is hoped, contribute to the development of 2'-modified-4'-thioRNAs, especially Me-SRNA, as a new RNA molecule for therapeutic applications.
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PMID:Synthesis and characterization of 2'-modified-4'-thioRNA: a comprehensive comparison of nuclease stability. 1915 Oct 85