Table 1.
Group I introns in bacteria and phage that encode homing endonuclease genes (HEGs)
| HEG family | Organisma | Taxonomyb | Genec | rDNA insertion sited | Intron size (nt) | HE size (aa) e | Functional HEsf | Accession number |
| LAGLIDADG | ||||||||
| * Synechococcus sp. C9 | Cyanobacteria | LSU | L1917 | 743 | 181 | DQ421380 | ||
| Thermotoga subterranea | Thermotogae | LSU | L1917 | 774 | 168 | AJ556793 | ||
| Simkania negevensis | Chlamydiae | LSU | L1931 | 654 | 143 | U68460 | ||
| * Synechococcus lividus (strain C1) | Cyanobacteria | LSU | L1931 | 675 | 162 | DQ421379 | ||
| * Synechococcus sp. C9 | Cyanobacteria | LSU | L1931 | 666 | 167 | DQ421380 | ||
| Thermotoga naphthophila | Thermotogae | LSU | L1931 | 699 | 162 | AJ556785 | ||
| Thermotoga neapolitana | Thermotogae | LSU | L1931 | 700 | 162 | AJ556784 | ||
| Thermotoga petrophila | Thermotogae | LSU | L1931 | 698 | 162 | AJ556786 | ||
| Coxiella burnetii | Proteobacteria | LSU | L1951 | 720 | 157 | AE016828 | ||
| * Synechococcus lividus (strain C1) | Cyanobacteria | LSU | L2593 | 744 | 189 | DQ421379 | ||
| * Synechococcus sp. C9 | Cyanobacteria | LSU | L2593 | 748 | 159 | DQ421380 | ||
| Thermosynechococcus elongatus | Cyanobacteria | LSU | L2593 | 745 | 175 | AP005376 | ||
| GIY-YIG | ||||||||
| ● Escherichia coli phage T4 | Phage | sunY/nrdD | - | 1033 | 258 | I-TevII | NC_000866 | |
| ● Escherichia coli phage T4 | Phage | td | - | 1017 | 245 | I-TevI | NC_000866 | |
| Bacillus mojavensis | Firmicutes | thyA | 1122 | 266 | I-BmoI | AF321518 | ||
| Bacillus subtilis phage β22 | Phage | thy | - | 392 | pseudo | L31962 | ||
| ○ Bacillus anthracis | Firmicutes | nrdE (prophage) | - | 1102 | 253 | I-BanI | NC_003997 | |
| H-N-H | ||||||||
| ● T-even phage RB3 | Phage | nrdB | - | 1090 | 269 | I-TevIII | X59078 | |
| Bacillus phage SPO1 | Phage | DNA pol | - | 882 | 174 | I-HmuI | M37686 | |
| Bacillus phage SP82 | Phage | DNA pol | - | 915 | 185 | I-HmuII | U04812 | |
| Bacillus phage ϕe | Phage | DNA pol | - | 903 | 181 | U04813 | ||
| Escherichia coli phage ΦI | Phage | DNA pol | - | 601 | 131 | I-TslI | AY769989 | |
| Escherichia coli phage W31 | Phage | DNA pol | - | 601 | 131 | I-TslI | AY769990 | |
| Bacillus phage Spbeta | Phage | bnrdF | - | 808 | 173 | NC_001884 | ||
| Staphylococcal phage Twort | Phage | nrdE | - | 1087 | 243 | I-TwoI | AF485080 | |
| Bacillus thuringiensis phage Bastille | Phage | DNA pol | - | 853 | 188 | I-BasI | AY256517 | |
| Streptococcus thermophilus phage J1 | Phage | Lysin | - | 1013 | 253 | AF148566 | ||
| Lactobacillus delbrueckii subsp. lactis phage LL-H | Phage | terL | - | 837 | 168 | L37351 | ||
| PD-(D/E)XK | ||||||||
| Synechocystis sp. PCC 6803 | Cyanobacteria | tRNA-fMet | - | 655 | 150 | I-Ssp6803I | U10482 |
a Organism names. Intron hosts reported in this study are marked with asterisks. Filled circles indicate that homologous introns are found in closely related T-even-like phages [50] and the open circle indicates that homologous introns exist in closely related Bacillus species and strains [4], but are not included in this table.
b Classification of organisms follows that of the NCBI (National Center for Biotechnology Information) GenBank.
c The gene in which the intron is inserted.
d The numbering reflects the Escherichia coli genic position.
e HE length in amino acids (aa). HE gene fragments are indicated (pseudo).
f Active HE proteins that cut the intron minus target sites.