Homing endonucleases: Structure, function and evolution

Cellular and Molecular Life Sciences

Volumn 55, Issue 10, 1999, Pages 1304-1326

  Jurica, M S ^a   Stoddard, B L ^a  

^a UNIVERSITY OF WASHINGTON   (United States)

Author keywords

Crystallography; Homing endonuclease; Intein; Mobile intron

Indexed keywords

DNA; ENDONUCLEASE;

ALLELE; DNA STRAND BREAKAGE; ENZYME STRUCTURE; GENE REARRANGEMENT; GENE SEQUENCE; GENE STRUCTURE; GENE TRANSFER; INTRON; NONHUMAN; OPEN READING FRAME; REVIEW;

ANIMALS; DNA; DNA RESTRICTION ENZYMES; ENDODEOXYRIBONUCLEASES; EVOLUTION; GENETIC ENGINEERING; INTRONS; MODELS, MOLECULAR; NUCLEIC ACID CONFORMATION; PROTEIN CONFORMATION;

EID: 0033567272     PISSN: 1420682X     EISSN: None     Source Type: Journal    
DOI: 10.1007/s000180050372     Document Type: Review

References (110)

1. 1 Dujon B. (1989) Group I introns as mobile genetic elements: facts and mechanistic speculations - a review. Gene 82: 91-114
2. 2 Belfort M. and Roberts R. J. (1997) Homing endonucleases keeping the house in order. Nucleic Acids Res. 25: 3379-3388
3. 3 Belfort M. and Perlman P. S. (1995) Mechanisms of intron mobility. J. Biol. Chem. 270: 30237-30240
4. 4 Belfort M., Reaban M. E., Coetzee T. and Dalgaard J. Z. (1995) Prokaryotic introns and inteins: a panoply of form and function. J. Bacteriol. 177: 3897-3903
5. 5 Lambowitz A. M. and Belfort M. (1993) Introns as mobile genetic elements. Annu. Rev. Biochem. 62: 587-622
6. 6 Lambowitz A. M., Caprara M. G., Zimmerly S. and Perlman P. S. (1998) Group I and group II ribozymes as RNPs: clues to the past and guides to the future. In: RNA World II, vol. 37, pp. 451-485 Gesteland, R. F., Cech, T. R. and Atkins, J. F. (ed.), Cold Spring Harbor Press, Cold Spring Harbor, NY
7. 7 Mueller J. E., Brysk M., Loizos N. and Belfort M. (1993) Homing endonucleases. In: Nucleases, vol. 2, pp. 111-143, Linn S. M., Lloyd R. S. and Roberts R. J. (eds), Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY
8. 8 Coen D., Deutsch J., Netter P., Petrochilo E. and Slonimski P. P. (1970) Mitochondrial genetics. I. Methodology and phenomenology. Symp. Soc. Exp. Biol. 23: 449-496
9. 9 Dujon B. (1980) Sequence of the intron and flanking exons of the mitochondrial 21S rRNA gene of yeast strains having different alleles at the omega and rib-1 loci. Cell 20: 185-197
10. 10 Bos J. L., Heyting C., Borst P., Arnberg A. C. and Van Bruggen E. F. (1978) An insert in the single gene for the large ribosomal RNA in yeast mitochondrial DNA. Nature 275: 336-338
11. 11 Zinn A. R. and Butow R. A. (1985) Nonreciprocal exchange between alleles of the yeast mitochondrial 21S rRNA gene: kinetics and the involvement of a double-strand break. Cell 40: 887-895
12. 12 Colleaux L., d'Auriol L., Betermier M., Cottarel G., Jacquier A., Galibert F. et al. (1986) Universal code equivalent of a yeast mitochondrial intron reading frame is expressed into E. coli as a specific double strand endonuclease. Cell 44: 521-533
13. 13 Macreadie I. G., Scott R. M., Zinn A. R. and Butow R. A. (1985) Transposition of an intron in yeast mitochondria requires a protein encoded by that intron. Cell 41: 395-402
14. 14 Jacquier A. and Dujon B. (1985) An intron-encoded protein is active in a gene conversion process that spreads an intron into a mitochondrial gene. Cell 41: 383-394
15. 15 Argast G. M., Stephens K. M., Emond M. J. and Monnat R. J. J. (1998) I-Ppo1 and I-Cre1 homing site sequence degeneracy determined by random mutagenesis and sequential in vitro enrichment. J. Mol. Biol. 280: 345-353
16. 16 Aggarwal A. K. and Wah D. A. (1998) Novel site-specific DNA endonucleases, Curr. Opin. Struct. Biol. 8: 19-25
17. 17 Aagaard C., Awayez M. J. and Garrett R. A. (1997) Profile of the DNA recognition site of the archaeal homing endonuclease I-Dmo1. Nucleic Acids Res. 25: 1523-1530
18. 18 Lykke-Andersen J., Thi-Ngoc H. P. and Garrett R. A. (1994) DNA substrate specificity and cleavage kinetics of an archaeal homing-type endonuclease from Pyrobaculum organotrophum. Nucleic Acids Res. 22: 4583-4590
19. 19 Perrin A., Buckle M. and Dujon B. (1993) Asymmetrical recognition and activity of the I-Sce1 endonuclease on its site and on intron-exon junctions. EMBO J. 12: 2939-2947
20. 20 Bryk M., Belisle M., Mueller J. E. and Belfort M. (1995) Selection of a remote cleavage site by I-Tev1, the td intron-encoded endonuclease. J. Mol. Biol. 247: 197-210
21. 21 Quirk S. M., Bell-Pedersen D. and Belfort M. (1989) Intron mobility in the T-even phages: high frequency inheritance of group I introns promoted by intron open reading frames. Cell 56: 455-465
22. 22 Quirk S. M., Bell-Pedersen D., Tomaschewski J., Ruger W. and Belfort M. (1989) The inconsistent distribution of introns in the T-even phages indicates recent genetic exchanges. Nucleic Acids Res. 17: 301-315
23. 23 Lemieux B., Turmel M. and Lemieux C. (1988) Unidirectional gene conversions in the chloroplast of Chlamydomonas inter-specific hybrids. Mol. Gen. Genet. 212: 48-55
24. 24 Muscarella D. E. and Vogt V. M. (1989) A mobile group I intron in the nuclear rDNA of Physarum polycephalum. Cell 56: 443-454
25. 25 Wenzlau J. M., Saldanha R. J., Butow R. A. and Perlman P. S. (1989) A latent intron-encoded maturase is also an endonuclease needed for intron mobility. Cell 56: 421-430
26. 26 Michel F. and Ferat J.-L. (1995) Structure and activities of group II introns. Ann. Rev. Biochem. 64: 435-461
27. 27 Curcio M. J. and Belfort M. (1996) Retrohoming: cDNA-mediated mobility of group II introns requires a catalytic RNA. Cell 84: 9-12
28. 28 Bell-Pedersen D., Quirk S. M., Aubrey M. and Belfort M. (1989) A site-specific endonuclease and co-conversion of flanking exons associated with the mobile td intron of phage T4. Gene 82: 119-126
29. 29 Clyman J. and Belfort M. (1992) Trans and cis requirements for intron mobility in a prokaryotic system. Genes Dev. 6: 1269-1279
30. 30 Mueller J. E., Clyman J., Huang Y. J., Parker M. M. and Belfort M. (1996) Intron mobility in phage T4 occurs in the context of recombination-dependent DNA replication by way of multiple pathways. Genes Dev. 10: 351-364
31. 31 Lazowska J., Meunier B. and Macadre C. (1994) Homing of a group II intron in yeast mitochondrial DNA is accompanied by unidirectional co-conversion of upstream-located markers. EMBO J. 13: 4963-4972
32. 32 Moran J. V., Zimmerly S., Eskes R., Kennell J. C., Lambowitz A. M., Butow R. A. et al. (1995) Mobile group II introns of yeast mitochondrial DNA are novel site-specific retroelements. Mol. Cell. Biol. 15: 2828-2838
33. 33 Kennell J. C., Moran J. V., Perlman P. S., Butow R. A. and Lambowitz A. M. (1993) Reverse transcriptase activity associated with maturase-encoding group II introns in yeast mitochondria. Cell 73: 133-146
34. 34 Zimmerly S., Guo H., Perlman P. S. and Lambowitz A. M. (1995) Group II intron mobility occurs by target DNA-primed reverse transcription. Cell 82: 545-554
35. 35 Zimmerly S., Guo H., Eskes R., Yang J., Perlman P. S. and Lambowitz A. M. (1995) A group II intron RNA is a catalytic component of a DNA endonuclease involved in intron mobility. Cell 83: 529-538
36. 36 Yang J., Mohr G., Perlman P. S. and Lambowitz A. M. (1998) Group II intron mobility in yeast mitochondria target DNA-primed reverse transcription activity of all and reverse splicing into DNA transposition sites in vitro. J. Mol. Biol. 282: 505-523
37. 37 Yang J., Zimmerly S., Perlman P. S. and Lambowitz A. M. (1996) Efficient integration of an intron RNA into double-stranded DNA by reverse splicing [see comments]. Nature 381: 332-335
38. 38 Cousineau B., Smith D., Cavanagh S. L., Mueller J. E., Yang J., Mills D. et al. (1998) Retrohoming of a bacterial group II intron: mobility via complete reverse splicing, independent of homologous DNA recombination. Cell 94: 451-462
39. 39 Dalgaard J. Z., Klar A. J., Moser M. J., Holley W. R., Chatterjec A. and Mian I. S. (1997) Statistical modeling and analysis of the LAGLIDADG family of site-specific endonucleases and identification of an intein that encodes a site-specific endonuclease of the HNH family. Nucleic Acids Res. 25: 4626-4638
40. 40 Heath P. J., Stephens K. M., Monnat R. J. and Stoddard B. L. (1997) The structure of I-Cre1, a group I intron-encoded homing endonuclease. Nature Struct. Biol. 4: 468-476
41. 41 Jurica M. S., Monnat R. J. and Stoddard B. L. (1998) DNA recognition and cleavage by the LAGLIDADG homing endonuclease I-Cre1. Mol. Cell 2: 469-476
42. 42 Duan X., Gimble F. S. and Quiocho F. A. (1997) Crystal structure of PI-Sce1, a homing endonuclease with protein splicing activity. Cell 89: 555-564
43. 43 Silva G. H., Dalgaard J. Z., Belfort M. and Roey P. V. (1999) Crystal structure of the thermostable archaeal intron-encoded endonuclease I-Dmo1. J. Mol. Biol. 286: 1123-1136
44. 44 Johansen S., Embley T. M. and Willassen N. P. (1993) A family of nuclear homing endonucleases. Nucleic Acids Res. 21: 4405-4411
45. 45 Muscarella D. E., Ellison E. L., Ruoff B. M. and Vogt V. M. (1990) Characterization of I-Ppo, an intron-encoded endonuclease that mediates homing of a group I intron in the ribosomal DNA of Physarum polycephalum. Mol. Cell. Biol. 10: 3386-3396
46. 46 Flick K. E., McHugh D., Heath J. D., Stephens K. M. Jr., R. J. M. and Stoddard B. L. (1997) Crystallization and preliminary X-ray studies of I-Ppo1: a nuclear, intron-encoded homing endonuclease from Physarum polycephalum, Protein Sci. 6: 2677-2680
47. 47 Ellison E. L. and Vogt V. M. (1993) Interaction of the intron-encoded mobility endonuclease I-Ppo1 with its target site. Mol. Cell. Biol. 13: 7531-7539
48. 48 Whittmayer P. K. and Raines R. T. (1996) Substrate binding and turnover by the highly specific I-Ppo1 endonuclease. Biochemistry 35: 1076-1083
49. 49 Wittmayer P. K., McKenzie J. L. and Raines R. T. (1998) Degenerate DNA recognition by I-Ppo1 endonuclease. Gene 206: 11-21
50. 50 Lowery R., Hung L., Knoche K. and Bandziulis R. (1992) Properties of I-Ppo1: a rare-cutting intron-encoded endonuclease. Promega Notes 38: 8-12
51. 51 Flick K. E., Jurica M. S., Monnat R. J. and Stoddard B. L. (1998) DNA binding and cleavage by the nuclear intron-encoded homing endonuclease I-Ppo1. Nature 394: 96-101
52. 52 Bryk M., Quirk S. M., Mueller J. E., Loizos N., Lawrence C. and Belfort M. (1993) The td intron endonuclease I-Tev1 makes extensive sequence-tolerant contacts across the minor groove of its DNA target. EMBO J. 12: 4040-4041
53. 53 Derbyshire V., Kowalski J. C., Dansereau J. T., Hauer C. R. and Belfort M. (1997) Two-domain structure of the td intron-encoded endonuclease I-Tev1 correlates with the two-domain configuration of the homing site. J. Mol. Biol. 265: 494-506
54. 54 Shub D. A., Goodrich-Blair H. and Eddy S. R. (1994) Amino acid sequence motif of group I intron endonucleases is conserved in open reading frames of group II introns. Trends Biochem. Sci. 19: 402-404
55. 55 Gorbalenya A. E. (1994) Self-splicing group I and group II introns encode homologous (putative) DNA endonucleases of a new family. Protein Sci. 3: 1117-1120
56. 56 Eddy S. R. and Gold L. (1991) The phage T4 nrdB intron: a deletion mutant of a version found in the wild. Genes Dev. 5: 1032-1041
57. 57 Goodrich-Blair H. and Shub D. A. (1996) Beyond homing: competition between intron endonucleases confers a selective advantage on flanking genetic markers. Cell 84: 211-221
58. 58 Matsuura M., Saldanha R., Ma H., Wank H., Yang J., Mohr G. et al. (1997) A bacterial group II intron encoding reverse transcriptase, maturase, and DNA endonuclease activities: biochemical demonstration of maturase activity and insertion of new genetic information within the intron. Genes Dev. 11: 2910-2924
59. 59 Pietrokovki S. (1998) Modular organization of inteins and C-terminal autocatalytic domains. Protein Sci. 63: 64-71
60. 60 Gorbalenya A. E. (1998) Non-canonical inteins. Nucleic Acids Res. 26: 1741-1748
61. 61 Colleaux L., D'Auriol L., Galibert F. and Dujon B. (1988) Recognition and cleavage site of the intron-encoded omega transposase. Proc. Natl. Acad. Sci. USA 85: 6022-6026
62. 62 Thompson A. J., Yuan X., Kudlicki W. and Herrin D. L. (1992) Cleavage and recognition pattern of a double-strand-specific endonuclease (I-Cre1) encoded by the chloroplast 23S rRNA intron of Chlamydomonas reinhardtii. Gene 119: 247-251
63. 63 Seligman L. M., Stephens K. M., Savage J. H. and Monnat R. J. (1997) Genetic analysis of the Chlamydomonas reinhardtii I-Cre1 mobile intron homing system in Escherichia coli. Genetics 147: 1653-1664
64. 64 Wang J., Kim H.-H., Yuan X. and Herrin D. L. (1997) Purification, biochemical characterization and protein-DNA interactions of the I-Cre1 endonuclease produced in Escherichia coli. Nucleic Acids Res. 25: 3767-3776
65. 65 Gimble F. S. and Wang J. (1996) Substrate recognition and induced DNA distortion by the PI-Sce1 endonuclease, an enzyme generated by protein splicing. J. Mol. Biol. 263: 163-180
66. 66 Bell-Pedersen D., Quirk S. M., Bryk M. and Belfort M. (1991) I-Tev1, the endonuclease encoded by the mobile td intron, recognizes binding and cleavage domains on its DNA target. Proc. Natl. Acad. Sci. USA 88: 7719-7723
67. 67 Van Ommen G.-J. B., Boer P. H., Goot G. S. P., Haan M. D., Roosendaal E. and Grivell L. A. (1980) Mutations affecting RNA splicing and the interaction of gene expression of the yeast mitochondrial loci cob and oxi-3. Cell 20: 173-183
68. 68 Perlman P. S., Mahler H. R., Dhawale S., Hanson D. and Alexander N. J. (1980) Alternate forms of the COB/BOX gene: some new observations. In: The Organization and Expression of the Mitochondrial Genome, vol. 2, pp. 161-172, Kroon A. M. and Saccone C. (eds), North-Holland Biomedical Press, New York
69. 69 Lazowska J., Jacq C. and Slonimski P. P. (1980) Sequence of introns and flanking exons in wild-type and box3 mutants of cytochrome b reveals an interlaced splicing protein coded by an intron. Cell 22: 333-348
70. 70 Guo Q. and Lambowitz A. M. (1992) A tyrosyl-tRNA synthetase binds specifically to the group I intron catalytic-core. Genes Dev. 6: 1357-1372
71. 71 Shaw L. C. and Lewin A. S. (1995) Protein-induced folding of a group I intron in cytochrome b pre-mRNA. J. Biol. Chem. 270: 21552-21562
72. 72 Weeks K. M. and Cech T. R. (1996) Assembly of a ribonucleoprotein catalyst by tertiary structure capture. Science 271: 345-348
73. 73 Lambowitz A. M. and Perlman P. S. (1990) Involvement of aminoacyl-tRNA synthetases and other proteins in group I and group II intron splicing. Trends. Biochem. Sci. 15: 367-382
74. 74 Schafer B., Wilde B., Massardo D. R., Manna F., Del Giudice L. and Wolf K. (1994) A mitochondrial group-I intron in fission yeast encodes a maturase and is mobile in crosses. Curr. Genet. 25: 336-341
75. 75 Szezepanek T. and Lazowska J. (1996) Replacement of two non-adjacent amino acids in the S. cerevisiae bi2 intron-encoded RNA maturase is sufficient to gain a homing-endonuclease activity. EMBO J. 15: 3758-3767
76. 76 Dujardin G., Jacq C. and Slonimski P. P. (1982) Single base substitution in an intron of oxidase gene compensates splicing defects of the cytochrome b gene. Nature 298: 628-632
77. 77 Ho Y., Kim S. J. and Waring R. B. (1997) A protein encoded by a group I intron in Aspergillus nidulans directly assists RNA splicing and is a DNA endonuclease [published erratum appears in Proc. Natl. Acad. Sci. USA (1997) 94: 14976]. Proc. Natl. Acad. Sci. USA 94: 8994-8999
78. 78 Mills D. A., McKay L. L. and Dunny G. M. (1996) Splicing of a group II intron involved in the conjugative transfer of pRS01 in Lactococci. J. Bacteriol. 178: 3531-3538
79. 79 Shearman C., Godon J.-J. and Gasson M. (1996) Splicing of a group II intron in a functional transfer gene of Lactococcus lactis. Mol. Microbiol. 21: 45-53
80. 80 Sugita M., Shinozaki K. and Sugiura M. (1985) Tobacco chloroplast tRNA-Lys (UUU) gene contains a 2.5-kilobase-pair intron: an open reading frame and a conserved boundary sequence in the intron. Proc. Natl. Acad. Sci. USA 82: 3557-3561
81. 81 Bonitz S. G., Coruzzi G., Thalenfeld B. E. and Tzagoloff A. (1980) Assembly of the mitochondrial membrane system. Structure and nucleotide sequence of the gene coding for subunit I of yeast cytochrome oxidase. J. Biol. Chem. 255: 11927-11941
82. 82 Kane P. M., Yamashiro C. T., Wolczyk D. F., Neff N., Goebl M. and Stevens T. H. (1990) Protein splicing converts the yeast TFP1 gene product of the 69-kD subunit of the vacuolar H ( + )-adenosine triphosphatase. Science 250: 651-657
83. 83 Shao Y. and Kent S. B. (1997) Protein splicing: occurrence, mechanisms and related phenomena. Chem. Biol. 4: 187-194
84. 84 Cooper A. A. and Stevens T. H. (1995) Protein splicing: self-splicing of genetically mobile elements at the protein level. Trends Biochem. Sci. 20: 351-356
85. 85 Pietrokovski S. (1994) Conserved sequence features of inteins (protein introns) and their use in identifying new inteins and related proteins. Protein Science 3: 2340-2350
86. 86 Derbyshire V., Wood D. W., Wu W., Dansereau J. T., Dalgaard J. Z. and Belfort M. (1997) Genetic definition of a protein-splicing domain: functional mini-inteins support structure predictions and a model for intein evolution. Proc. Natl. Acad. Sci. USA 94: 11466-11471
87. 87 Shingledecker K., Jiang S.-Q. and Paulus H. (1998) Molecular dissection of the Mycobacterium tuberculosis RecA intein: design of a minimal intein and of a trans-splicing system involving two intein fragments. Gene 207: 187-195
88. 88 He Z., Crist M., Yen H., Duan X., Quiocho F. A. and Gimble F. S. (1998) Amino acid residues in both the protein splicing and endonuclease domains of the PI-Sce1 intein mediate DNA binding. J. Biol. Chem. 273: 4607-4615
89. 89 Liu X.-Q. and Hu Z. (1997) A DnaB intein in Rhodothermus marinus: indication of recent intein homing across remotely related organisms. Proc. Natl. Acad. Sci. USA 94: 7851-7856
90. 90 Jin Y., Binkowski G., Simon L. D. and Norris D. (1997) Ho endonuclease cleaves MAT DNA in vitro by an inefficient stoichiometric reaction mechanism. J. Biol. Chem. 272: 7352-7359
91. 91 Nickoloff J. A., Singer J. D. and Heffron F. (1990) In vivo analysis of the Saccharomyces cerevisiae HO nuclease recognition site by site-directed mutagenesis. Mol. Cell. Biol. 10: 1174-1179
92. 92 Durrenberger F. and Rochaix J.-D. (1991) Chloroplast ribosomal intron of Chlamydomonas reinhardtii: in vitro self-splicing DNA endonuclease activity and in vivo mobility. EMBO J. 10: 3495-3501
93. 93 Herrin D. L., Chen Y.-F. and Schmidt G. W. (1990) RNA splicing in Chlamydomonas cholorplasts: self-splicing of 23S pre RNA. J. Biol. Chem. 265: 21134-21140
94. 94 Rochaix J.-D., Rahire M. and Michel F. (1985) The choloroplast ribosomal intron of Chlamydomonas reinhardtii chloroplast codes for a polypeptide related to mitochondrial maturases. Nucleic Acids Res. 13: 975-984
95. 95 Gimble F. S. and Thorner J. (1992) Homing of a DNA endonuclease by meitoic gene conversion in Saccharomyces cerevisiae. Nature 357: 301-306
96. 96 Gimble F. S. and Stephens B. W. (1995) Substitutions in conserved dodecapeptide motifs that uncouple the DNA binding and DNA cleavage activities of PI-Sce1 endonuclease. J. Biol. Chem. 270: 5849-5856
97. 97 Dalgaard J. Z., Garrett R. A. and Belfort M. (1993) A site-specific endonuclease encoded by a typical archaeal intron. Proc. Natl. Acad. Sci. USA 90: 5414-5417
98. 98 Dalgaard J. Z., Garrett R. A. and Belfort M. (1994) Purification and characterization of two forms of I-Dmo1, a thermophilic site-specific endonuclease encoded by an archaeal intron. J. Biol. Chem. 269: 28885-28892
99. 99 Mueller J. E., Smith D., Byrk M. and Belfort M. (1995) Intron-encoded endonuclease I-Tev1 binds as a monomer to effect sequential cleavage via conformational changes in the td homing site. EMBO J. 14: 5724-5735
100. 100 Kowalski J. C., Belfort M., Stapleton M. A., Holpert M., Dansereau J. T., Pietrokovski S. et al. (1999) Configuration of the catalytic GYI-YIG domain of intron endonuclease I-Tev1: coincidence of computational and molecular findings. Nucleic Acids Res. (in press)
101. 101 Phillips S. E. V. (1994) The β-ribbon DNA recognition motif. Ann. Rev. Biophys. Biomol. Struct. 23: 671-701
102. 102 Turmel M., Otis C., Cote V. and Lemieux C. (1997) Evolutionarily conserved and functionally important residues in the I-Ceu1 homing endonuclease. Nucleic Acids Res. 25: 2610-2619
103. 103 Friedhoff P., Kolmes B., Gimadutdinow O., Wende W., Krause K. L. and Pingoud A. (1996) Analysis of the mechanism of the Serratia nuclease using site-directed mutagenesis. Nucleic Acids Res. 24: 2632-2639
104. 104 Miller M. D., Tanner J., Alpaugh M., Benedik M. J. and Krause K. L. (1994) 2.1 A structure of Serratia endonuclease suggests a mechanism for binding to double-stranded DNA. Nature Struct. Biol. 1: 461-468
105. 105 Friedhoff P., Franke I., Mesiss G., Wende W., Krause K. L. and Pingoud A. (1999) A similar active site for non-specific and specific endonucleases. Nature Struct. Biol. 6: 112
106. 106 Friedhoff P., Franke I., Krause K. L. and Pingoud A. (1999) Cleavage experiments with deoxythymidine 3′,5′-bis-(p-nitrophenyl phosphate) suggest that the homing endonuclease I-Ppo1 follows the same mechanism of phosphodiester bond hydrolysis as the non-specific Serratia nuclease. FEBS Lett. 443: 209-214
107. 107 Derbyshire V., Grindley N. D. F. and Joyce C. M. (1991) The 3′-5′ exonuclease of DNA polymerase I of Escherichia coli: contribution of each amino acid at the active site of the reaction. EMBO J. 10: 17-24
108. 108 Beintema J. J. and Kleineidam R. G. (1998) The ribonuclease A superfamily: general discussion. Cell. Mol. Life Sci. 54: 825-832
109. 109 Pingoud A. and Jeltsch A. (1997) Recognition and cleavage of DNA by type-II restriction endonucleases. Eur. J. Biochem. 246: 1-22
110. 110 Aggarwal A. K. (1995) Structure and function of restriction endonucleases. Curr. Opin. Struct. Biol. 5: 11-19