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Comment
. 2000 Aug 15;97(17):9351-3.
doi: 10.1073/pnas.97.17.9351.

Resolving the relationships of resolving enzymes

D M Lilley  1 , M F White
Affiliations
Comment

Resolving the relationships of resolving enzymes

D M Lilley et al. Proc Natl Acad Sci U S A. .
No abstract available

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Figures

Figure 1
Figure 1
Conserved motifs in cellular junction-resolving enzymes. (A) Sequence alignment showing the four sequence motifs common to the mitochondrial, eubacterial, and pox viral Holliday junction resolving enzymes. The residue numbering for E. coli RuvC is indicated below the sequences. The four conserved acid residues highlighted in red (D7, E66, D138, and D142) cluster in the active site of the RuvC crystal structure (11), where they provide ligands for the catalytic metal ions. Mutagenesis studies have shown that all four of these acidic residues are essential for catalysis, as are the equivalent residues E145 (E66) and D294 (D138) in the S. cerevisiae enzyme. Basic residues conserved between RuvC and some representatives of both the mitochondrial and pox enzymes are highlighted in blue. Only one, K107, is absolutely conserved in all sequences. Conserved neutral amino acids (yellow) probably play important structural roles. Sequences are: S. cere, Saccharomyces Cce1 (GenBank no. 416770); C. albi, Candida Cce1 (17); S. pombe, Schizosaccharomyces Cce1 (GenBank no. 1256525); Vaccin, Vaccinia virus A22 protein (GenBank no. 93258); Myxoma, myxoma virus A22 homolog (GenBank no. 6523967); Mollusc, Molluscum virus A22 homolog (GenBank no. 1492070); Yaba, monkey pox virus A22 homolog (GenBank no. 6682807); RuvC, E. coli RuvC (GenBank no. 95767). (B) The four acidic residues (red) and four basic residues (blue) conserved in the eubacterial, mitochondrial, and pox viral junction resolving enzymes are highlighted by using a space-filling representation of a RuvC monomer (11). The residues all group around the active site, suggesting that motifs I to IV of A are conserved because of common roles in substrate recognition and catalysis.
Figure 2
Figure 2
Superfamilies containing Holliday junction-resolving enzymes. Structural studies of diverse metal ion-dependent nucleases have revealed the existence of two superfamilies. The integrase superfamily, whose founding member is RNaseH, includes viral transposases and integrases as well as the Holliday junction resolving enzymes RuvC, Cce1, and poxviral A22. The nuclease superfamily, with founder member EcoRV, includes all of the type II and probably all of the type I restriction enzymes, as well as diverse DNA repair endo- and exonucleases, the archaeal resolving enzyme Hjc, and T7 endonuclease I. The bacteriophage resolving enzymes RusA and T4 endonuclease VII cannot be assigned to either of these superfamilies at present, although the lineage of the former may be discernible on solution of the crystal structure. The line lengths above bear no relationship to the degree of divergence of family members.
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Comment on

References

    1. White M F, Giraud-Panis M-J E, Pöhler J R G, Lilley D M J. J Mol Biol. 1997;269:647–664. - PubMed
    1. Iwasaki H, Takahagi M, Shiba T, Nakata A, Shinagawa H. EMBO J. 1991;10:4381–4389. - PMC - PubMed
    1. Connolly B, Parsons C A, Benson F E, Dunderdale H J, Sharples G J, Lloyd R G, West S C. Proc Natl Acad Sci USA. 1991;88:6063–6067. - PMC - PubMed
    1. Kleff S, Kemper B, Sternglanz R. EMBO J. 1992;11:699–704. - PMC - PubMed
    1. Komori K, Sakae S, Shinagawa H, Morikawa K, Ishino Y. Proc Natl Acad Sci USA. 1999;96:8873–8878. - PMC - PubMed

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