Any feedback?
Information on EC 3.2.1.108 - lactase
for references in articles please use BRENDA:EC3.2.1.108Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
EC Tree
3.2.1.108 lactaseIUBMB Comments
The enzyme from intestinal mucosa contains two glycosyl hydrolase domains, both of which belong to glycosyl hydrolase family 1 (GH1). While the first domain catalyses the activity described here, the second domain catalyses the reaction of EC 3.2.1.62 glycosylceramidase. cf. EC 3.2.1.33 amylo-alpha-1,6-glucosidase.
Specify your search results
Word Map
- 3.2.1.108
- sucrase
- milk
- maltase
- intolerance
- disaccharidase
-
brush
- border
- mucosal
- jejunal
- gastrointestinal
- malabsorption
- breath
- children
-
dairy
-
wean
- villus
-
diarrhea
- enterocytes
- infant
- bowel
- ileum
- hypolactasia
-
suckling
-
crypt
- duodenal
- aminopeptidase
-
piglets
- trehalase
-
brush-border
-
non-persistence
- sucrase-isomaltase
-
maldigestion
-
adult-type
-
yogurt
- glucoamylase
-
3.2.1.23
- isomaltase
- lactulose
-
bloating
-
small-intestinal
- microvillus
-
coeliac
-
flatulence
-
archaeological
- maltase-glucoamylase
- medicine
-
crypt-villus
- pharmacology
- food industry
- cellobiase
-
carbohydrases
-
formula-fed
-
pastor
The expected taxonomic range for this enzyme is: Eukaryota, Bacteria
Synonyms
lactase, intestinal lactase, lactase/phlorizin hydrolase, lactase phlorizin-hydrolase, lactase-phlorizin hydrolase lph, 
more
topPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
lactase
lactase phlorizin hydrolase
lactase-phlorizin hydrolase
lactase/phlorizin hydrolase
-
-
-
-
LCT
-
-
-
-
LPH
lactase-phlorizin hydrolase
-
-
-
-
LPH
-
-
-
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
lactose + H2O = D-galactose + D-glucose
-
-
-
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
hydrolysis
hydrolysis of O-glycosyl bond
hydrolysis of O-glycosyl bond
-
-
-
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
SYSTEMATIC NAME
IUBMB Comments
lactose galactohydrolase (configuration-retaining)
The enzyme from intestinal mucosa contains two glycosyl hydrolase domains, both of which belong to glycosyl hydrolase family 1 (GH1). While the first domain catalyses the activity described here, the second domain catalyses the reaction of EC 3.2.1.62 glycosylceramidase. cf. EC 3.2.1.33 amylo-alpha-1,6-glucosidase.
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
CAS REGISTRY NUMBER
COMMENTARY
9031-11-2
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
2-O-beta-D-galactopyranosyl-D-xylose + H2O
D-galactose + D-xylose
-
-
-
-
?
3-O-beta-D-galactopyranosyl-D-xylose + H2O
D-galactose + D-xylose
-
-
-
-
?
4-O-beta-D-galactopyranosyl-D-xylose + H2O
D-galactose + D-xylose
-
-
-
-
?
5-bromo-4-chloro-3-indolyl-beta-D-fucopyranoside + H2O
?
-
37°C, 1 hour, full-length lactase, mature lactase, cytosolic form of mature lactase
-
-
?
fluorescein-di-beta-D-galactopyranoside + H2O
?
-
only cytosolic form of mature lactase
-
-
?
lactose + H2O
galactose + D-glucose
-
reaction is not inhibited by 2-fluoro-dinotrophenylglucoside
-
-
?
methyl-beta-D-glucoside + H2O
methanol + beta-D-glucose
-
7.3% of the activity with lactose
-
-
?
o-nitrophenyl-beta-glucoside + H2O
o-nitrophenol + beta-D-glucose
-
13% of the activity with lactose
-
-
?
phenyl-beta-galactoside + H2O
phenol + beta-D-galactose
-
0.1% of the activity with lactose
-
-
?
phlorizin + H2O
?
-
reaction is inhibited by 2-fluoro-dinotrophenylglucoside
-
-
?
quercetin-3-glucoside + H2O
quercetin + D-glucose
-
reaction is marginally inhibited by 2-fluoro-dinotrophenylglucoside
-
-
?
quercetin-4'-glucoside + H2O
quercetin + D-glucose
-
reaction is marginally inhibited by 2-fluoro-dinotrophenylglucoside
-
-
?
5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside + H2O
?
-
37°C, 1 h
-
-
?
5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside + H2O
?
-
37°C, 1 hour, only cytosolic form of mature lactase
-
-
?
baohuoside I + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
cellobiose + H2O
2 beta-D-glucose
-
14% of the activity with lactose
-
-
?
daidzein 7-O-beta-D-glucopyranoside + H2O
daidzein + beta-D-glucose
-
-
-
-
?
epimedin A + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
epimedin B + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
epimedin C + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
icariin + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
lactose + H2O
D-galactose + D-glucose
-
-
-
-
?
lactose + H2O
D-galactose + D-glucose
-
the nuclear transcription factor Oct-1 binds to the T variant at position -13910 upstream of the lactase gene and enhances transcription of the lactase gene
-
-
?
lactose + H2O
D-galactose + D-glucose
-
-
-
-
?
lactose + H2O
D-galactose + D-glucose
-
in rats grown under iron deficiency lactase-phlorizin hydrolase activity was 56.8% lower compared to control rats
-
-
?
lactose + H2O
D-glucose + D-galactose
-
rotavirus RRV infection affects the lactose metabolism of enterocytes in the intestine, overview
-
-
?
o-nitrophenyl-beta-galactoside + H2O
o-nitrophenol + beta-D-galactose
-
17% of the activity with lactose
-
-
?
o-nitrophenyl-beta-galactoside + H2O
o-nitrophenol + beta-D-galactose
-
15.4% of the activity with lactose
-
-
?
p-nitrophenyl-beta-galactoside + H2O
p-nitrophenol + beta-D-galactose
-
13% of the activity with lactose
-
-
?
p-nitrophenyl-beta-galactoside + H2O
p-nitrophenol + beta-D-galactose
-
9.3% of the activity with lactose
-
-
?
p-nitrophenyl-beta-glucoside + H2O
p-nitrophenol + beta-D-glucose
-
10% of the activity with lactose
-
-
?
p-nitrophenyl-beta-glucoside + H2O
p-nitrophenol + beta-D-glucose
-
12.7% of the activity with lactose
-
-
?
phlorizin + H2O
phloretin + D-glucose
-
at 2.3% of the activity with lactose
-
-
?
additional information
?
-
-
total lactase activity increases to reach maximal levels around weaning, and remains high subsequently, enzyme activity appears to be regulated during development predominantly by transcription mechanism, while alterations during lactation, and along the proximal to distal gradient, are the result of other control mechanism
-
-
?
additional information
?
-
-
absorption of quercetin-3-glucoside requires hydrolysis by the enzyme, absorption of quercetin-4-glucoside requires both an interaction with sodium-dependent glucose transporter and hydrolysis by the enzyme
-
-
?
additional information
?
-
-
enzyme plays a major role in metabolism of glycosylated phytochemicals
-
-
?
additional information
?
-
-
the enzyme has two distinct catalytic active sites, one for the hydrolysis of lactose and flavonoid glucosides and another, phlorizin hydrolase, for the hydrolysis of phlorizin and glucosylceramides
-
-
?
additional information
?
-
-
activity by the isolated intestinal enzyme on flavonoid glucosides in descending order: icariin, epimedin A, epimedin C, epimedin B, amd baohuoside I, mass spectrometric product analysis, detailed overview
-
-
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
baohuoside I + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
epimedin A + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
epimedin B + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
epimedin C + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
icariin + H2O
? + D-glucose
-
from Yinyanghuo (Herba Epimdii, YYH) is a popular Traditional Chinese Medicine tonic for kidney-reinforcing from Epimedium koreanum Nakai herb extract
-
-
?
lactose + H2O
D-galactose + D-glucose
-
the nuclear transcription factor Oct-1 binds to the T variant at position -13910 upstream of the lactase gene and enhances transcription of the lactase gene
-
-
?
lactose + H2O
D-galactose + D-glucose
-
-
-
-
?
lactose + H2O
D-galactose + D-glucose
-
in rats grown under iron deficiency lactase-phlorizin hydrolase activity was 56.8% lower compared to control rats
-
-
?
lactose + H2O
D-glucose + D-galactose
-
rotavirus RRV infection affects the lactose metabolism of enterocytes in the intestine, overview
-
-
?
additional information
?
-
-
total lactase activity increases to reach maximal levels around weaning, and remains high subsequently, enzyme activity appears to be regulated during development predominantly by transcription mechanism, while alterations during lactation, and along the proximal to distal gradient, are the result of other control mechanism
-
-
?
additional information
?
-
-
absorption of quercetin-3-glucoside requires hydrolysis by the enzyme, absorption of quercetin-4-glucoside requires both an interaction with sodium-dependent glucose transporter and hydrolysis by the enzyme
-
-
?
additional information
?
-
-
enzyme plays a major role in metabolism of glycosylated phytochemicals
-
-
?
additional information
?
-
-
the enzyme has two distinct catalytic active sites, one for the hydrolysis of lactose and flavonoid glucosides and another, phlorizin hydrolase, for the hydrolysis of phlorizin and glucosylceramides
-
-
?
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
2-fluoro-dinitrophenylglucoside
-
specifically inhibits phlorizin hydrolase, lactase activity is inhibited slowly
D-glucal
-
40% inhibition for 4-O-beta-D-galactopyranosyl-D-xylose and 75% inhibition for 3-O-beta-D-galactopyranosyl-D-xylose at 100 mM D-glucal, no increase of inhibition above 100 mM D-glucal
epigallocatechin-3-gallate
-
inhibition by epigallocatechin-3-gallate of lactase is alleviated about 1.7fold by proline-rich proteins
NSP4
-
impairment of lactase activity observed during rotavirus infection results from an inhibitory action of the secreted non-structural rotavirus protein NSP4
-
thyroxine
-
administration of thyroxine to 8-day-old pups shows a decline in lactase activity
additional information
-
rotavirus impairs lactase enzymatic activity by an NSP4-dependant mechanism in brush border of human enterocyte-like Caco-2 cells, the infected brush border membranes show an enzyme with altered kinetics, overview
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
ACTIVATING COMPOUND
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
cortisone
-
administration of cortisone to 8-day-old pups augments lactase activity
additional information
-
determination of disaccharidase activities in intestinal biopsy samples show a highly significant correlation between lactase activity and the T/G-13915 genotype
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
22.2
2-O-beta-D-galactopyranosyl-D-xylose
-
100 mM sodium maleate buffer, pH 6.0, 25°C
8.5
3-O-beta-D-galactopyranosyl-D-xylose
-
100 mM sodium maleate buffer, pH 6.0, 25°C
58.8
4-O-beta-D-galactopyranosyl-D-xylose
-
100 mM sodium maleate buffer, pH 6.0, 25°C
additional information
additional information
-
rotavirus infection decreases Vmax of LPH, overview
-
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
IC50 VALUE [mM]
INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.074
epigallocatechin-3-gallate
Rattus norvegicus
-
in the absence of proline-rich protein fraction, in 1.5 mM sodium phosphate buffer (pH 6.8), at 37°C
0.126
epigallocatechin-3-gallate
Rattus norvegicus
-
in the presence of proline-rich protein fraction, in 1.5 mM sodium phosphate buffer (pH 6.8), at 37°C
Please wait a moment until the data is sorted. This message will disappear when the data is sorted.
SPECIFIC ACTIVITY [µmol/min/mg]
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
0.00167
-
rhesus monkey rotavirus-, RRV, infected cells, lactase enzyme activity in cell homogenates
0.00219
-
rhesus monkey rotavirus-, RRV, infected cells, lactase enzyme activity in brush border-enriched fraction
0.0033
-
rats are force-fed a low-strach diet, with thyroid hormone treatment
0.00344
-
non-infected cells, lactase enzyme activity in brush border-enriched fraction
0.00359
-
UV, psoralen-inactivated RRV infected cells, lactase enzyme activity in brush border-enriched fraction
0.005
0.0067
-
rats are fed a low-starch diet, starved for 3 days, and thyroid hormones are injected daily after the diet
0.0083
0.17
-
administration of thyroxine to 8-day-old pups, activity in suckling rat intes