Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The HpaII restriction-modification system from Haemophilus parainfluenzae recognizes the DNA sequence CCGG. The gene for the HpaII methylase has been cloned into E. coli and its nucleotide sequence has been determined. The DNA of the clones is fully protected against cleavage by the HpaII restriction enzyme in vitro, indicating that the methylase gene is active in E. coli. The clones were isolated in an McrA-strain of E. coli; attempts to isolate them in an McrA+ strain were unsuccessful. The clones do not express detectable HpaII restriction endonuclease activity, suggesting that either the endonuclease gene is not expressed well in E. coli, or that it is not present in its entirety in any of the clones that we have isolated. The derived amino acid sequence of the HpaII methylase shows overall similarity to other cytosine methylases. It bears a particularly close resemblance to the sequences of the HhaI, BsuFI and MspI methylases. When compared with three other methylases that recognize CCGG, the variable region of the HpaII methylase, which is believed to be responsible for sequence specific recognition, shows some similarity to the corresponding regions of the BsuFI and MspI methylases, but is rather dissimilar to that of the SPR methylase.
 ...
PMID:Cloning and characterization of the HpaII methylase gene. 218 89

DNA methyltransferase activity is not normally found in yeast. To investigate the response of Saccharomyces cerevisiae to the presence of methylated bases, we introduced the Bacillus subtilis SPR phage DNA-[cytosine-5] methyltransferase gene on the shuttle vector, YEp51. The methyltransferase gene was functionally expressed in yeast under the control of the inducible yeast GAL 10 promoter. Following induction we observed a time-dependent methylation of yeast DNA in RAD+ and rad2 mutant strains; the rad2 mutant is defective in excision-repair of UV-induced DNA damage. Analysis of restriction endonuclease digestion patterns revealed that the relative amount of methylated DNA was greater in the excision defective rad2 mutant than in the RAD+ strain. These data indicate that the yeast excision-repair system is capable of recognizing and removing m5C residues.
 ...
PMID:The UV excision-repair system of Saccharomyces cerevisiae is involved in the removal of methylcytosines formed in vivo by a cloned prokaryotic DNA methyltransferase. 269 55

We have compared the deduced amino acid (aa) sequences of the EcoRII restriction endonuclease (R.EcoRII) and the proposed specificity (target recognition) domains of three DNA-[cytosine-C5] methyltransferases (MTases), M.EcoRII, M.Dcm, and M.SPR, each of which recognizes the same nucleotide sequence, CCWGG (where W is A or T). We have identified a region containing sequence motifs that are partially conserved in the MTases and R.EcoRII. This may be the first example of aa sequence homology between a MTase specificity (target recognition) domain and its cognate restriction endonuclease (ENase). It suggests that this region is important for DNA recognition by R.EcoRII and that the EcoRII ENase and MTase genes may have evolved from a common progenitor.
 ...
PMID:Sequence motifs common to the EcoRII restriction endonuclease and the proposed sequence specificity domain of three DNA-[cytosine-C5] methyltransferases. 844 14

Currently, influenza PAN endonuclease has become an attractive target for development of new drugs to treat influenza infections. Herein we report the discovery of new PAN endonuclease inhibitors derived from a chelating agent dopamine moiety. A series of dopamine amide derivatives and their conformationally constrained 1,2,3,4-tetrahydroisoquinoline-6,7-diol-based analogs were elaborated and assayed against influenza virus A/WSN/33 (H1N1). Most compounds exhibited moderate to excellent antiviral activities, generating a preliminary SARs. Among them, compounds 14 and 19 showed stronger anti-IAV activity compared with the reference Peramivir. Moreover, 14 and 19 demonstrated a concentration-dependent inhibition of PAN endonuclease based on both FRET assay and SPR assay. Docking studies were also performed to elucidate the binding mode of 14 and 19 with the PAN protein and to identify amino acids involved in their mechanism of action, which were well consistent with the biological data. This finding was beneficial to laying the foundation for the rational development of more effective PAN endonuclease inhibitors.
 ...
PMID:Synthesis and SARs of dopamine derivatives as potential inhibitors of influenza virus PAN endonuclease. 3195 81