HMM Summary Page: TIGR03239

AccessionTIGR03239
NameGarL
Function2-dehydro-3-deoxyglucarate aldolase
Gene SymbolgarL
Trusted Cutoff406.75
Domain Trusted Cutoff406.75
Noise Cutoff372.15
Domain Noise Cutoff372.15
Isology Typeequivalog
EC Number4.1.2.20
HMM Length249
AuthorSelengut J
Entry DateJan 4 2007 5:03PM
Last ModifiedFeb 14 2011 3:27PM
CommentIn E. coli this enzyme (GarL, [1,2]) 2-dehydro-3-deoxyglucarate aldolase acts in the catabolism of several sugars including D-galactarate, D-glucarate and L-idarate. In fact, 5-dehydro-4-deoxy-D-glucarate aldolase is a synonym for this enzyme as it is unclear in the literature whether the enzyme acts on only one of these or, as seems likely, has no preference. (Despite the apparent large difference in substrate stucture indicated by their names, 2-DH-3DO- and 5-DH-4DO-glucarate differ only by the chirality of most central hydroxyl-bearing carbon and is alternately named 2-DH-3DO-galactarate.) The reported product of D-galactarate dehydratase (4.2.1.42) is the 5DH-4DO-glucarate isomer and this enzyme is found proximal to the aldolase in many genomes (GenProp0714) where no epimerase is known. Similarly, the product of D-glucarate dehydratase (4.2.1.40) is again the 5-DH-4DO isomer, so the provenance of the 2-DH-3DO-glucarate isomer for which this enzyme is named is unclear.
ReferencesRN [1] RM PMID: 9772162 RT Evolution of enzymatic activities in the enolase superfamily: characterization of the (D)-glucarate/galactarate catabolic pathway in Escherichia coli. RA Hubbard BK, Koch M, Palmer DR, Babbitt PC, Gerlt JA RL Biochemistry. 1998 Oct 13;37(41):14369-75. RN [2] RM PMID: 10921867 RT Crystal structures of the metal-dependent 2-dehydro-3-deoxy-galactarate aldolase suggest a novel reaction mechanism. RA Izard T, Blackwell NC RL EMBO J. 2000 Aug 1;19(15):3849-56. DR HAMAP; MF_01291; 22 of 24
Genome PropertyGenProp0714: galactarate utilization via tartronate semi-aldehyde (HMM)
GenProp0716: glucarate utilization via tartronate semi-aldehyde (HMM)