Mutarotase converts alpha-aldose to the beta-anomer. It is active on D-glucose, L-arabinose, D-xylose, D-galactose, maltose and lactose. Sus scrofa (taxid: 9823) EC: 5EC: .EC: 1EC: .EC: 3EC: .EC: 3
Score = 174 (66.3 bits), Expect = 8.5e-13, P = 8.5e-13
Identities = 37/76 (48%), Positives = 47/76 (61%)
Query: 10 GTDRSFL---SLEFSF-HRALDPESGRYMEVHTDQPGIQFYTGNYIP-EMSGKKGATYTK 64
G D +F S E F R SGR +EV+T QPG+QFYTGN++ + GK G Y K
Sbjct: 241 GFDHNFCLKESKEKKFCARVHHAASGRILEVYTTQPGVQFYTGNFLDGTLKGKSGEVYPK 300
Query: 65 HCAYCFETQNFPNAVN 80
H +C ETQN+P+AVN
Sbjct: 301 HSGFCLETQNWPDAVN 316
Score = 96.8 bits (242), Expect = 3e-25
Identities = 30/58 (51%), Positives = 38/58 (65%)
Query: 24 RALDPESGRYMEVHTDQPGIQFYTGNYIPEMSGKKGATYTKHCAYCFETQNFPNAVNI 81
R PESGR +EV+T QPG+QFYTGN++ G G Y K +C ETQ+FP+A N
Sbjct: 247 RLTSPESGRKLEVYTTQPGVQFYTGNFLDGTPGGGGKVYGKRSGFCLETQHFPDAPNH 304
Galactose mutarotase catalyzes the conversion of beta-D-galactose to alpha-D-galactose. Beta-D-galactose is produced by the degradation of lactose, a disaccharide composed of beta-D-glucose and beta-D-galactose. This epimerization reaction is the first step in the four-step Leloir pathway, which converts galactose into metabolically important glucose. This epimerization step is followed by the phosophorylation of alpha-D-galactose by galactokinase, an enzyme which can only act on the alpha anomer. A glutamate and a histidine residue of the galactose mutarotase have been shown to be critical for catalysis, the glutamate serves as the active site base to initiate the reaction by removing the proton from the C-1 hydroxyl group of the sugar substrate, and the histidine as the active site acid to protonate the C-5 ring oxygen. Galactose mutarotase is a member of the aldose-1-epimerase superfamily. Length = 326
Score = 64.3 bits (157), Expect = 3e-13
Identities = 22/63 (34%), Positives = 31/63 (49%), Gaps = 2/63 (3%)
Query: 27 DPESGRYMEVHTDQPGIQFYTGNYIPEMSGKKGATYTKHCAYCFETQNFPNAVNIHRSSW 86
P+ +EV T+QP +Q YTGN++ + G Y H ETQ P++ N W
Sbjct: 257 SPDEDLSLEVFTNQPALQIYTGNFLAGTPNRGGKKYVDHAGIALETQFLPDSPN--HPEW 314
Query: 87 GKI 89
G I
Sbjct: 315 GDI 317
Members of this protein family act as galactose mutarotase (D-galactose 1-epimerase) and participate in the Leloir pathway for galactose/glucose interconversion. All members of the seed alignment for this model are found in gene clusters with other enzymes of the Leloir pathway. This enzyme family belongs to the aldose 1-epimerase family, described by Pfam model pfam01263. However, the enzyme described as aldose 1-epimerase itself (EC 5.1.3.3) is called broadly specific for D-glucose, L-arabinose, D-xylose, D-galactose, maltose and lactose. The restricted genome context for genes in this family suggests members should act primarily on D-galactose. Length = 336
Members of this protein family act as galactose mutarotase (D-galactose 1-epimerase) and participate in the Leloir pathway for galactose/glucose interconversion. All members of the seed alignment for this model are found in gene clusters with other enzymes of the Leloir pathway. This enzyme family belongs to the aldose 1-epimerase family, described by pfam model pfam01263. However, the enzyme described as aldose 1-epimerase itself (EC 5.1.3.3) is called broadly specific for D-glucose, L-arabinose, D-xylose, D-galactose, maltose and lactose. The restricted genome context for genes in this family suggests members should act primarily on D-galactose.
Galactose mutarotase catalyzes the conversion of beta-D-galactose to alpha-D-galactose. Beta-D-galactose is produced by the degradation of lactose, a disaccharide composed of beta-D-glucose and beta-D-galactose. This epimerization reaction is the first step in the four-step Leloir pathway, which converts galactose into metabolically important glucose. This epimerization step is followed by the phosophorylation of alpha-D-galactose by galactokinase, an enzyme which can only act on the alpha anomer. A glutamate and a histidine residue of the galactose mutarotase have been shown to be critical for catalysis, the glutamate serves as the active site base to initiate the reaction by removing the proton from the C-1 hydroxyl group of the sugar substrate, and the histidine as the active site acid to protonate the C-5 ring oxygen. Galactose mutarotase is a member of the aldose-1-epimerase superfamily.
>COG2017 GalM Galactose mutarotase and related enzymes [Carbohydrate transport and metabolism]
Proteins similar to Escherichia coli YihR are uncharacterized members of aldose-1-epimerase superfamily. Aldose 1-epimerases or mutarotases are key enzymes of carbohydrate metabolism, catalyzing the interconversion of the alpha- and beta-anomers of hexose sugars such as glucose and galactose. This interconversion is an important step that allows anomer specific metabolic conversion of sugars. Studies of the catalytic mechanism of the best known member of the family, galactose mutarotase, have shown a glutamate and a histidine residue to be critical for catalysis; the glutamate serves as the active site base to initiate the reaction by removing the proton from the C-1 hydroxyl group of the sugar substrate, and the histidine as the active site acid to protonate the C-5 ring oxygen.
>cd09021 Aldose_epim_Ec_YphB aldose 1-epimerase, similar to Escherichia coli YphB
Proteins similar to Escherichia coli YphB are uncharacterized members of the aldose-1-epimerase superfamily. Aldose 1-epimerases or mutarotases are key enzymes of carbohydrate metabolism, catalyzing the interconversion of the alpha- and beta-anomers of hexose sugars such as glucose and galactose. This interconversion is an important step that allows anomer specific metabolic conversion of sugars. Studies of the catalytic mechanism of the best known member of the family, galactose mutarotase, have shown a glutamate and a histidine residue to be critical for catalysis; the glutamate serves as the active site base to initiate the reaction by removing the proton from the C-1 hydroxyl group of the sugar substrate, and the histidine as the active site acid to protonate the C-5 ring oxygen.
1.3.3 from EC) (mutarotase) is the enzyme responsible for the anomeric interconversion of D-glucose and other aldoses between their alpha- and beta-forms. The sequence of mutarotase from two bacteria, Acinetobacter calcoaceticus and Streptococcus thermophilus is available []. It has also been shown that, on the basis of extensive sequence similarities, a mutarotase domain seems to be present in the C-terminal half of the fungal GAL10 protein which encodes, in the N-terminal part, UDP-glucose 4-epimerase.; GO: 0016853 isomerase activity, 0005975 carbohydrate metabolic process; PDB: 1YGA_A 3DCD_A 2CIQ_A 2CIS_A 2CIR_A 2HTB_C 2HTA_B 3Q1N_A 1NSZ_B 1NSR_B ....
Aldose 1-epimerases or mutarotases are key enzymes of carbohydrate metabolism; they catalyze the interconversion of the alpha- and beta-anomers of hexose sugars such as glucose and galactose. This interconversion is an important step that allows anomer specific metabolic conversion of sugars. Studies of the catalytic mechanism of the best known member of the family, galactose mutarotase, have shown a glutamate and a histidine residue to be critical for catalysis; the glutamate serves as the active site base to initiate the reaction by removing the proton from the C-1 hydroxyl group of the sugar substrate and the histidine as the active site acid to protonate the C-5 ring oxygen.
>cd09025 Aldose_epim_Slr1438 Aldose 1-epimerase, similar to Synechocystis Slr1438
Proteins similar to Synechocystis Slr1438 are uncharacterized members of aldose-1-epimerase superfamily. Aldose 1-epimerases or mutarotases are key enzymes of carbohydrate metabolism, catalyzing the interconversion of the alpha- and beta-anomers of hexose sugars such as glucose and galactose. This interconversion is an important step that allows anomer specific metabolic conversion of sugars. Studies of the catalytic mechanism of the best known member of the family, galactose mutarotase, have shown a glutamate and a histidine residue to be critical for catalysis; the glutamate serves as the active site base to initiate the reaction by removing the proton from the C-1 hydroxyl group of the sugar substrate, and the histidine as the active site acid to protonate the C-5 ring oxygen.
>cd09024 Aldose_epim_lacX Aldose 1-epimerase, similar to Lactococcus lactis lacX
Proteins similar to Lactococcus lactis lacX are uncharacterized members of aldose-1-epimerase superfamily. Aldose 1-epimerases or mutarotases are key enzymes of carbohydrate metabolism, catalyzing the interconversion of the alpha- and beta-anomers of hexose sugars such as glucose and galactose. This interconversion is an important step that allows anomer specific metabolic conversion of sugars. Studies of the catalytic mechanism of the best known member of the family, galactose mutarotase, have shown a glutamate and a histidine residue to be critical for catalysis; the glutamate serves as the active site base to initiate the reaction by removing the proton from the C-1 hydroxyl group of the sugar substrate, and the histidine as the active site acid to protonate the C-5 ring oxygen.
Score = 104 bits (262), Expect = 2e-28
Identities = 17/57 (29%), Positives = 23/57 (40%), Gaps = 1/57 (1%)
Query: 24 RALDPESGRYMEVHTDQPGIQFYTGNYIPEMSGKKGATYTKHCAYCFETQNFPNAVN 80
R +SG + + T P I Y ++ GKKG Y + A E Q A N
Sbjct: 257 RFWSEKSGIELSITTSYPVIHLYASKFLDC-KGKKGEHYKANKALAIEPQFHSAAPN 312
>3imh_A Galactose-1-epimerase; structural genomics, PSI-2, protein ST initiative, NEW YORK SGX research center for structural GEN nysgxrc; 1.76A {Lactobacillus acidophilus} Length = 338
HI1317; hypothetical protein, structure 2 function
85.97
>3imh_A Galactose-1-epimerase; structural genomics, PSI-2, protein ST initiative, NEW YORK SGX research center for structural GEN nysgxrc; 1.76A {Lactobacillus acidophilus}
Score = 74.1 bits (181), Expect = 2e-17
Identities = 17/59 (28%), Positives = 24/59 (40%), Gaps = 1/59 (1%)
Query: 22 FHRALDPESGRYMEVHTDQPGIQFYTGNYIPEMSGKKGATYTKHCAYCFETQNFPNAVN 80
+ R +SG + + T P I Y ++ GKKG Y + A E Q A N
Sbjct: 245 YLRFWSEKSGIELSITTSYPVIHLYASKFLDCK-GKKGEHYKANKALAIEPQFHSAAPN 302
