1. 2.6.1.7 enzyme   kynurenine transaminase (cyclizing)
                      kynurenine aminotransferase
                      L-kynurenine aminotransferase
                      kynurenine-oxoglutarate transaminase
                      kynurenine 2-oxoglutarate transaminase
                      L-kynurenine:2-oxoglutarate aminotransferase

2. 4.2.1.73 enzyme   protoaphin dehydratase (cyclizing)
                      protoaphin-aglucone dehydratase (cyclizing)
                      protoaphin-aglucone hydro-lyase (cyclizing)
                      protoaphin dehydratase

3. 4.2.2.15 enzyme   glycoconjugate sialyl-lyase (2,7-cyclizing)
                      sialglycoconjugate N-acylneuraminylhydrolase (2,7-cyclizing)
                      anhydroneuraminidase
                      anhydrosialidase
                      sialidase L

4. 5.4.99.17 enzyme   squalene mutase (cyclizing)
                      squalene-hopene cyclase

5. 1.1.3.40 enzyme   mannitol:oxygen oxidoreductase (cyclizing)
                      mannitol oxidase
                      D-arabitol oxidase
                      D-mannitol oxidase

6. 1.21.3.2 enzyme   columbamine:oxygen oxidoreductase (cyclizing)
                      berberine synthase
                      columbamine oxidase

7. 1.21.4.1 enzyme   5-aminopentanoate:lipoate oxidoreductase (cyclizing)
                      D-proline reductase (dithiol)

8. 1.4.4.1 enzyme   5-aminopentanoate:lipoate oxidoreductase (cyclizing)
                      D-proline reductase (dithiol)

9. 2.4.1.19 enzyme   alpha-1,4-glucan 4-glycosyltransferase, cyclizing
                      1,4-alpha-D-glucan 4-alpha-D-(1,4-alpha-D-glucano)-transferase (cyclizing)
                      BMA
                      CGTase
                      konchizaimu
                      cyclodextrin glucanotransferase
                      cyclodextrin glycosyltransferase
                      cyclomaltodextrin glucanotransferase
                      cyclomaltodextrin glucotransferase
                      cyclomaltodextrin glycosyltransferase
                      Bacillus macerans amylase
                      alpha-cyclodextrin glucanotransferase
                      alpha-cyclodextrin glycosyltransferase
                      beta-cyclodextrin glucanotransferase
                      beta-cyclodextrin glycosyltransferase
                      gamma-cyclodextrin glycosyltransferase
                      neutral-cyclodextrin glycosyltransferase

10. 2.5.1.4 enzyme   S-adenosyl-L-methionine alkyltransferase (cyclizing)
                      adenosylmethioninase
                      adenosylmethionine cyclotransferase

11. 2.5.1.5 enzyme   D-galactose-6-sulfate:alkyltransferase (cyclizing)
                      porphyran sulfatase
                      galactose 6-sulfatase
                      galactose-6-sulfatase
                      galactose-6-sulfurylase

12. 2.6.1.63 enzyme   L-kynurenine:glyoxylate aminotransferase (cyclizing)
                      kynurenine-glyoxylate aminotransferase
                      kynurenine-glyoxylate transaminase

13. 3.1.27.1 enzyme   ribonucleate nucleotido-2'-transferase (cyclizing)
                      RNAase CL
                      RNase II
                      RNase M
                      RNase Ms
                      RNase T2
                      acid RNase
                      acid ribonuclease
                      nonspecific RNase
                      ribonuclease II
                      ribonuclease M
                      ribonuclease N2
                      ribonuclease PP3
                      ribonuclease T2
                      ribonuclease U4
                      nonbase-specific RNase
                      Escherichia coli ribonuclease II
                      RNase (non-base specific)
                      base-non-specific ribonuclease
                      non-base specific ribonuclease
                      ribonnuclease (non-base specific)
                      ribonuclease (non-base specific)
                      ribonucleate 3'-oligonucleotide hydrolase
                      Escherichia coli ribonuclease I' ribonuclease PP2

14. 3.1.27.2 enzyme   ribonucleate nucleotido-2'-transferase (cyclizing)
                      Bacillus subtilis ribonuclease
                      Proteus mirabilis RNase

15. 3.1.27.3 enzyme   ribonuclease guaninenucleotido-2'-transferase (cyclizing)
                      binase
                      guanyloribonuclease
                      RNase F1
                      RNase G
                      RNase N1
                      RNase N2
                      RNase Sa
                      RNase T1
                      ribonuclease C2
                      ribonuclease Ch
                      ribonuclease F1
                      ribonuclease N1
                      ribonuclease N3
                      ribonuclease PP1
                      ribonuclease SA
                      ribonuclease T1
                      ribonuclease U1
                      Aspergillus oryzae ribonuclease
                      guanyl-specific RNase

16. 4.2.1.48 enzyme   D-glutamate hydro-lyase (cyclizing)
                      D-glutamate cyclase

17. 4.2.1.75 enzyme   hydroxymethylbilane hydro-lyase (cyclizing)
                      porphobilinogenase
                      URO-synthase
                      uroporphyrinogen isomerase
                      uroporphyrinogen III cosynthase
                      uroporphyrinogen-III synthase

18. 4.3.1.12 enzyme   L-ornithine ammonia-lyase (cyclizing)
                      ornithine cyclase
                      ornithine cyclodeaminase
                      ornithine cyclase (deaminating)

19. 4.3.1.4 enzyme   5-formimidoyltetrahydrofolate ammonia-lyase (cyclizing)
                      formimidoyltetrahydrofolate cyclodeaminase
                      formiminotetrahydrofolate cyclodeaminase

20. 4.6.1.1 enzyme   ATP diphosphate-lyase (cyclizing)
                      adenylylcyclase
                      adenyl cyclase
                      adenylate cyclase
                      3',5'-cyclic AMP synthetase

21. 4.6.1.15 enzyme   FAD-AMP lyase (cyclizing)
                      FMN cyclase
                      FAD AMP-lyase (cyclic-FMN-forming)

22. 4.6.1.2 enzyme   GTP diphosphate-lyase (cyclizing)
                      guanyl cyclase
                      guanylate cyclase
                      guanylyl cyclase

23. 4.6.1.6 enzyme   CTP diphosphate-lyase (cyclizing)
                      cytidyl cyclase
                      cytidylate cyclase
                      cytidylyl cyclase
                      3',5'-cyclic-CMP synthase

24. 5.3.99.6 enzyme   (9Z)-(13S)-12,13-epoxyoctadeca-9,11,15-trienoate isomerase (cyclizing)
                      allene-oxide cyclase

25. 1.21.3.4 enzyme   sulochrin:oxygen oxidoreductase (cyclizing, (+)-specific)
                      sulochrin oxidase
                      sulochrin oxidase [(+)-bisdechlorogeodin-forming]

26. 1.21.3.5 enzyme   sulochrin:oxygen oxidoreductase (cyclizing, (-)-specific)
                      sulochrin oxidase
                      sulochrin oxidase [(-)-bisdechlorogeodin-forming]

27. 1.21.99.1 enzyme   beta-cyclopiazonate:(acceptor) oxidoreductase (cyclizing)
                      beta-cyclopiazonate dehydrogenase
                      beta-cyclopiazonate oxidocyclase
                      beta-cyclopiazonic oxidocyclase

28. 1.4.1.15 enzyme   L-lysine:NAD+ oxidoreductase (deaminating, cyclizing)
                      lysine dehydrogenase

29. 2.3.1.160 enzyme   acyl-CoA:16-epivellosimine O-acetyltransferase (cyclizing)
                      vinorine synthase

30. 2.3.2.4 enzyme   (5-L-glutamyl)-L-amino-acid 5-glutamyltransferase (cyclizing)
                      gamma-glutamylcyclotransferase
                      L-glutamic cyclase
                      gamma-L-glutamylcyclotransferase
                      gamma-glutamyl-amino acid cyclotransferase

31. 2.3.2.5 enzyme   L-glutaminyl-peptide gamma-glutamyltransferase (cyclizing)
                      glutaminyl cyclase
                      glutaminyl-peptide cyclotransferase
                      glutaminyl-tRNA cyclotransferase
                      glutaminyl-transfer ribonucleate cyclotransferase

32. 4.2.3.18 enzyme   copalyl-diphosphate diphosphate-lyase (cyclizing)
                      abietadiene synthase

33. 4.2.3.8 enzyme   geranylgeranyl-diphosphate diphosphate-lyase (cyclizing)
                      geranylgeranyl-diphosphate diphosphate-lyase (cyclizing, CASbene-forming)
                      casbene synthase
                      casbene synthetase

34. 4.3.2.4 enzyme   DNA-4,6-diamino-5-formamidopyrimidine C8-N9-lyase (cyclizing)
                      purine imidazole-ring cyclase

35. 5.4.99.7 enzyme   (S)-2,3-epoxysqualene mutase (cyclizing, lanosterol-forming)
                      lanosterol synthase
                      oxidosqualene cyclase
                      oxidosqualene-lanosterol cyclase
                      squalene epoxidase-cyclase
                      2,3-oxidosqualene cyclase
                      2,3-epoxysqualene lanosterol cyclase
                      2,3-oxidosqualene sterol cyclase
                      2,3-oxidosqualene-lanosterol cyclase
                      lanosterol 2,3-oxidosqualene cyclase
                      squalene 2,3-epoxide:lanosterol cyclase
                      squalene-2,3-oxide-lanosterol cyclase

36. 5.4.99.8 enzyme   (S)-2,3-epoxysqualene mutase (cyclizing, cycloartenol-forming)
                      cycloartenol synthase
                      2,3-epoxysqualene cycloartenol-cyclase
                      2,3-epoxysqualene-cycloartenol cyclase
                      2,3-oxidosqualene-cycloartenol cyclase
                      squalene-2,3-epoxide-cycloartenol cyclase

37. 2.1.1.79 enzyme   S-adenosyl-L-methionine:unsaturated-phospholipid methyltransferase (cyclizing)
                      CFA synthase
                      cyclopropane synthase
                      cyclopropane synthetase
                      unsaturated-phospholipid methyltransferase
                      cyclopropane fatty acid synthase
                      cyclopropane fatty acid synthetase
                      cyclopropane-fatty-acyl-phospholipid synthase

38. 2.3.1.146 enzyme   malonyl-CoA:cinnamoyl-CoA malonyltransferase (cyclizing)
                      pinosylvin synthase
                      stilbene synthase
                      pine stilbene synthase

39. 2.3.1.159 enzyme   malonyl-CoA:N-methylanthraniloyl-CoA malonyltransferase (cyclizing)
                      acridone synthase

40. 2.3.1.74 enzyme   malonyl-CoA:4-coumaroyl-CoA malonyltransferase (cyclizing)
                      CHS
                      DOCS
                      chalcone synthase
                      chalcone synthetase
                      flavanone synthase
                      6'-deoxychalcone synthase
                      naringenin-chalcone synthase

41. 2.3.1.94 enzyme   malonyl-CoA:propionyl-CoA malonyltransferase (cyclizing)
                      erythronolide synthase
                      erythronolide condensing enzyme

42. 2.3.1.95 enzyme   malonyl-CoA:4-coumaroyl-CoA malonyltransferase (cyclizing)
                      resveratrol synthase
                      stilbene synthase
                      trihydroxystilbene synthase

43. 4.1.3.36 enzyme   o-succinylbenzoyl-CoA 1,4-dihydroxy-2-naphthoate-lyase (cyclizing)
                      dihydroxynaphthoate synthase
                      naphthoate synthase
                      1,4-dihydroxy-2-naphthoate synthase

44. 4.2.3.16 enzyme   geranyldiphosphate diphosphate lyase [cyclizing, (4S)-limonene-forming]
                      (-)-(4S)-limonene synthase
                      (4S)-limonene synthase
                      4S-(-)-limonene synthase
                      geranyldiphosphate diphosphate lyase (limonene forming)

45. 1.21.3.1 enzyme   N-[(5S)-5-amino-5-carboxypentanoyl]-L-cysteinyl-D-valine:oxygen oxidoreductase (cyclizing)
                      isopenicillin-N synthase

46. 1.5.4.1 enzyme   pyrimidodiazepine:glutathione-disulfide oxidoreductase (ring-opening, cyclizing)
                      pyrimidodiazepine:oxidized-glutathione oxidoreductase  (ring-opening, cyclizing)
                      PDA synthase
                      pyrimidodiazepine synthase

47. 2.3.1.170 enzyme   malonyl-CoA:4-coumaroyl-CoA malonyltransferase (cyclizing, reducing)
                      6'-deoxychalcone synthase

48. 4.1.1.48 enzyme   1-(2-carboxyphenylamino)-1-deoxy-D-ribulose-5-phosphate carboxy-lyase (cyclizing)
                      indoleglycerol phosphate synthase
                      indoleglycerol phosphate synthetase
                      indole-3-glycerophosphate synthase
                      indole-3-glycerol-phosphate synthase

49. 4.2.1.24 enzyme   5-aminolevulinate hydro-lyase (adding 5-aminolevulinate and cyclizing)
                      aminolevulinate dehydratase
                      aminolevulinic dehydratase
                      porphobilinogen synthase
                      delta-aminolevulinate dehydratase
                      delta-aminolevulinic dehydratase
                      5-levulinic acid dehydratase
                      delta-aminolevulinic acid dehydrase
                      delta-aminolevulinic acid dehydratase

50. 4.2.3.14 enzyme   geranyl-diphosphate diphosphate-lyase (cyclizing, pinene-forming)
                      pinene synthase
                      beta-geraniolene synthase
                      (-)-(1S,5S)-pinene synthase
                      geranyldiphosphate diphosphate lyase (pinene forming)

51. 4.2.3.17 enzyme   geranylgeranyl-diphosphate diphosphate-lyase (cyclizing, taxadiene-forming)
                      taxadiene synthase

52. 4.2.3.20 enzyme   geranyl-diphosphate diphosphate-lyase [cyclizing, (+)-(4R)-limonene-forming]
                      (+)-limonene synthase
                      (R)-limonene synthase
                      geranyldiphosphate diphosphate lyase [(+)-(R)-limonene-forming]

53. 4.2.3.4 enzyme   3-deoxy-arabino-heptulonate-7-phosphate phosphate-lyase (cyclizing)
                      3-deoxy-arabino-heptulosonate-7-phosphate phosphate-lyase  (cyclizing)
                      dehydroquinate synthase
                      3-dehydroquinate synthase
                      3-dehydroquinate synthetase
                      5-dehydroquinate synthase
                      5-dehydroquinic acid synthetase

54. 6.5.1.4 enzyme   RNA-3'-phosphate:RNA ligase (cyclizing, AMP-forming)
                      RNA cyclase
                      RNA-3'-phosphate cyclase

55. 4.2.1.52 enzyme   L-aspartate-4-semialdehyde hydro-lyase (adding pyruvate and cyclizing)
                      dihydrodipicolinate synthase
                      dihydropicolinate synthetase
                      dihydrodipicolinic acid synthase

56. 4.2.3.10 enzyme   geranyl-diphosphate diphosphate-lyase [cyclizing, (-)-endo-fenchol-forming]
                      (-)-endo-fenchol cyclase
                      (-)-endo-fenchol synthase
                      geranyl pyrophosphate:(-)-endo-fenchol cyclase

57. 4.2.3.11 enzyme   geranyl-diphosphate diphosphate-lyase (cyclizing, sabinene-hydrate-forming)
                      sabinene hydrate cyclase
                      sabinene-hydrate synthase

58. 4.2.3.7 enzyme   2-trans,6-trans-farnesyldiphosphate diphosphate-lyase (cyclizing, pentalenene-forming)
                      pentalenene synthase
                      pentalenene synthetase

59. 4.6.1.12 enzyme   2-phospho-4-(cytidine 5'-diphospho)-2-C-methyl-D-erythritol CMP-lyase (cyclizing)
                      MECDP-synthase
                      2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase

60. 1.14.13.85 enzyme   2-(or 4-)dimethylallyl-(6aS,11aS)-3,6a,9- trihydroxypterocarpan,NADPH:oxygen oxidoreductase (cyclizing)
                      glyceollin synthase
                      dimethylallyl-3,6a,9-trihydroxypterocarpan cyclase

61. 4.2.3.19 enzyme   ent-copalyl-diphosphate diphosphate-lyase (cyclizing, ent-kaurene-forming)
                      ent-kaurene synthetase B, ent-copalyl-diphosphate diphosphate-lyase  (cyclizing)
                      ent-kaurene synthase
                      ent-kaurene synthase B

62. 4.2.3.21 enzyme   trans,trans-farnesyl-diphosphate diphosphate-lyase (cyclizing, vetispiradiene-forming)
                      HVS
                      pemnaspirodiene synthase
                      vetispiradiene cyclase
                      vetispiradiene synthase
                      vetispiradiene-forming farnesyl pyrophosphate cyclase

63. 4.2.3.6 enzyme   trans,trans-farnesyl-diphosphate diphosphate-lyase (cyclizing, trichodiene-forming)
                      sesquiterpene cyclase
                      trichodiene synthase
                      trichodiene synthetase
                      trans,trans-farnesyl-diphosphate sesquiterpenoid-lyase

64. 4.2.3.9 enzyme   trans,trans-farnesyl-diphosphate diphosphate-lyase (cyclizing, aristolochene-forming)
                      aristolochene synthase
                      sesquiterpene cyclase
                      trans,trans-farnesyl diphosphate aristolochene-lyase

65. 4.2.3.13 enzyme   2-trans,6-trans-farnesyl-diphosphate diphosphate-lyase (cyclizing, (+)-delta-cadinene-forming)
                      (+)-delta-cadinene synthase

66. 2.3.1.165 enzyme   acyl-CoA:malonyl-CoA C-acyltransferase (decarboxylating, oxoacyl-reducing, thioester-hydrolysing and cyclizing)
                      6-methylsalicylic acid synthase