Table 1.

Dissimilar Enzymes Catalyzing the Same Biochemical Reactions[i]

Enzyme activity (EC No.)Taxonomic representation[ii] PDB entryStructural folds[iii]
bacteriaarchaeaeukaryotes
Alcohol:NADP dehydrogenase ADH_CLOBE ADH3_SULSO ADH1_ENTHI 1DEH different
 (EC1.1.1.2)DHSO_BACSU ALDX_HUMAN 2ALR
Formate dehydrogenase FDHF_ECOLI FDHA_METFO 1FDI different
 (EC1.2.1.2) FDH_PSESR A64427 FDH_NEUCR 2NAD
Dihydrofolate reductase DYRA_ECOLI DYR_HALVO DYR_HUMAN 1DHF different
 (EC1.5.1.3) DYR2_ECOLI 1VIE
Peroxidase PERM_HUMAN 1MHL same,
 (EC1.11.1.7) PER1_ARAHY 1ARV  RMSD = 4.8
Chloroperoxidase PRXC_PSEPY 1BRO different
 (EC1.11.1.10) PRXC_CALFU 1CPO different
PRXC_CURIN 1VNC
Superoxide dismutase SODC_ECOLI SODC_HUMAN 1SPD different
 (EC1.15.1.1) SODF_ECOLI SODF_SULAC SODM_HUMAN 1ABM
Protein-tyrosine phosphatase PTPA_STRCO PPAC_BOVIN 1PHR different
 (EC3.1.3.48) YOPH_YEREN PTN1_HUMAN 2HNP
Cellulase GUNA_CLOCE GUNB_NEOPA 1EDG different
 (EC3.2.1.4) GUND_CLOTM GUN_PHAVU 1CLC different
GUN1_TRIRE 1CEL
Xylanase XYNA_STRLI S43846 1XAS different
 (EC3.2.1.8) XYNA_BACCI XYN2_TRIRE 1XNB
Chitinase CHIA_SERMA CHIT_BRUMA 1CTN different
 (EC3.2.1.14)YE15_HAEIN CHI1_ORYSA 2BAA
β-Galactosidase BGAL_ECOLI BGAL_KLULA 1BGL different
 (EC3.2.1.23)BGLA_THEMA BGAM_SULSO BGLC_MAIZE 1GOW
Lichenase GUB_BACLI YG46_YEAST 1GBG different
 (EC3.2.1.73) GUB_BACCI 1CEM different
GUB2_HORVU 1GHR
β-Lactamase AMPC_ENTCL 2BLT different
 (EC3.5.2.6) BLAB_BACFR 1ZNB
Fructose 1,6-bisphosphate ALF_ECOLI ALF_YEAST 1DOS same,
 aldolase (EC4.1.2.13) ALF_STACA ALFA_HUMAN 1FBA  RMSD = 3.4
Carbonic anhydraseCCMM_SYNP7 CAH_METTE 1THJ different
 (EC4.2.1.1) CAH1_HUMAN 2CBA
Peptidyl-prolyl isomerase FKBX_ECOLI FKB1_METJA FKBP_HUMAN 1FKD different
 (EC5.2.1.8) CYPB_ECOLI CYPB_HUMAN 2CPL
Chorismate mutase PHEA_ECOLI Y246_METJA CHMU_YEAST 1ECM different
 (EC5.4.99.5) CHMU_BACSU 1COM
DNA topoisomerase I TOP1_ECOLI TOPG_SULAC TOP3_YEAST 1ECL different
 (EC5.99.1.2) TOP1_YEAST 1OIS

[i] The full version of the table, including homologs of the enzymes found in each of the sequenced genomes, is available as a WWW supplement at http://ncbi.nlm.nih.gov/Complete_Genomes.

[ii] The proteins are listed under their SwissProt, GenBank, or Protein Data Base identifiers. The names of enzymes with experimentally demonstrated activity, shown in the first column, are in boldface type; the dash indicates absence of homologs in any of the sequenced genomes.

[iii] The data are from SCOP [http://scop.mrc-lmb.cam.ac.uk/scop(Hubbard et al. 1997)] and FSSP [http://www2.ebi.ac.uk./dali/fssp/fssp.html (Holm and Sander 1996a)] databases. RMSD of superimposed Cα atoms in the structural alignment of the two isoforms is from the FSSP database (Holm and Sander 1996a).