PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Glucosidases”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1975

[Glucosidases specific for the cyanogenic glucoside triglochinin. Purification and characterization of beta-glucosidases from Alocasia macrorrhiza Schott].

beta-Glucosidases have been isolated from Alocasia macrorrhiza plants. The enzymes are highly specific for the hydrolysis of the cyanogenic glucoside triglochinin endogenous to this plant. Upon chromatography of protein extracts on cation exchange resins and Sephadex G-200, separation into various enzymatically active bands was observed. The main fractions possess molecular weights of approximately 310000 and 105 000, as shown by preparative ultracentrifugation in a linear saccharose gradient. The beta-glucosidases are composed of subunits (molecular weight 55 000 to 60 000), as revealed by sodium dodecylsulfate gel electrophoresis. The result of alkaline disc electrophoresis and isoelectric focusing in polyacrylamide gel suggest that the beta-glucosidase fraction with molecular weight 105 000 is a dissociation product of the 310 000 molecular-weight species. The isoelectric points of the various beta-glocusidase bands, obtained by isoelectric focusing, vary between pH 4.5 and 5.0. The beta-glucosidases show a pronounced specificity for triglochinin. The Km for this substrate (3 times 10(-5) M) is 50 to 100-fold lower than for all other substrates hydrolyzed. Of the other cyanogenic glycosides, only those with an aromatic aglycone, (S)-configuration at the asymmetric carbon atom of the aglycone and glucose as sugar moiety were hydrolyzed to a measurable extent. The pH optimum of the enzyme reaction is 5.5, the temperature optimum around 50 degrees C. Cu2 ions and glucono-1,5-lactone inhibit beta-glucosidase activity approximately 50% at a concentration of 5 times 10(-4) M, while Hg2,Ag and p-chloromercuribenzoate show the same percent inhibition at 5 times 10(-7) M. Lipophilic solvents (ethanol, ethylene glycol monomethylether) activate the beta-glucosidase activity, preferentially by influencing the V values of the enzymes.

Chloromercuribenzoates↗
PubMed1975

Beta-Glucosidases from Cicer arietinum L. Purification and Properties of isoflavone-7-O-glucoside-specific beta-glucosidases.

Beta-Glucosidases specific for isoflavone 7-O-glucosides have been isolated from garbanzo plants, Cicer arietinum L. These aryl-beta-glucohydrolases occur in the different organs of the plant as multiple molecular forms. The major isoenzymes of the roots, the leaves and the hypocotyl were purified to electrophoretic homogeneity. When subjected to isoelectric focussing in polyac rylamide gels the electrophoretically homogeneous glucohydrolases were found to consist of one or two major and several minor enzymically active molecular species. In roots the beta-glucohydrolase isoenzymes constitute a considerable portion of the extractable protein, so that purification to an electrophoretically homogeneous form is easily attainable. All beta-glucosidases analyzed possess molecular weights in the range of 125 000 (ultracentrifugation) to 135 000 (Sephadex G-200) and contain two subunits of molecular weight near 68 000. The pH optimum for enzymic activity is 7--7.5 with a second optimum of 4.5--5. The isoelectric points of the various species range between pH 5.9 AND 7.1. Staining for glycoprotein was positive. Kinetic analysis demonstrated a pronounced specificity of the enzymes for aromatic substrates with glucose as the sugar moiety. alpha-Glucosides as well as disaccharides were not hydrolyzed at all. Isoflavone 7-O-glucosides are the most favoured substrates with a Km of 2 x 10(-5) M, while the Km with aromatic glucosides (i.e. salicin, 4-nitrophenyl glucoside) are 100 times larger. In addition the beta-glucosidases show a pronounced specificity for glucose in the 7-position of the flavonoid nucleus. Using isoflavone aglycones as substrates glucose transferase activity was also demonstrable. The beta-glucohydrolase activity is strongly inhibited by Hg2plus. This inhibition is partially reversible and preferentially influences the Km values of the enzymes compared to V. Agplus, glucono-1,5-lactone, ethyleneglycol monomethyl ether and glycerol are only weakly inhibitory, while glucose, p-chloromercuribenzoate and Cu2plus are without effect.

Flavonoids↗
PubMedDate not supplied

[Dextran glucosidase activity of the acid alpha-glucosidase from pig spleen].

Some properties of acid alpha-glucosidase from pig spleen are studied. Changes in the enzyme activity with respect to polymeric and oligomeric substrates were shown to take place under effects of temperature, pH, concentration of metal ions, urea treatment, trehalose inhibition. Dextran and glycogen were used as polymeric substrates, and disaccharides with different types of bonds were taken as oligomeric substrates. The data obtained confirm the hypothesis on separate regions of binding polymers and oligomers with the enzyme molecule.

Animals↗
PubMed1979

Use of immobilized antibodies in investigating acid alpha-glucosidase in urine in relation to Pompe's disease.

(1) A simple method is described for the isolation of the lysosomal enzyme, acid alpha-glucosidase (alpha-D-glucoside glucohydrolase, EC 3.2.1.20) from normal human liver. Antibodies raised against the purified enzyme were immobilized by covalent coupling to Sepharose 4B. (2) Acid alpha-glucosidase can be quantitatively removed from normal urine by incubating with an excess of immobilized antibody. With p-nitrophenyl-alpha-glucoside as substrate, acid alpha-glucosidase accounts for 91 +/- 3% of the total alpha-glucosidase activity at pH 4.0 IN Normal urine. (3) In urine from a patient with the infantile form of Pompe's disease ('acid maltase deficiency'), no alpha-glucosidase activity could be removed by the immobilized antibody, in agreement with the fact that acid alpha-glucosidase is absent in these patients. (4) In urine from patients with the late-onset form of Pompe's disease, 46 +/- 11% of the alpha-glucosidase activity at pH 4.0 can be removed by incubation with immobilized antibodies, indicating that residual acid alpha-glucosidase activity is present in urine of these patients. The residual acid alpha-glucosidase activity amounts to about 5% of that in the urine of control persons. (5) If acid alpha-glucosidase is adsorbed to immobilized antibodies, the activity can still be measured with p-nitrophenyl-alpha-glucoside as substrate. The Km for p-nitrophenyl-alpha-glucoside is not significantly changed by adsorbing purified acid alpha-glucosidase to immobilized antibodies. (6) The properties of acid alpha-glucosidase from urine of patients with late-onset Pompe's disease were compared with those of acid alpha-glucosidase from normal urine, both adsorbed to immobilized antiserum. The pH-activity profile of the enzyme from urine of patients with late-onset Pompe's disease can not be distinguished from that of the normal urinary enzyme. The Km for p-nitro-phenyl-alpha-glucoside of the two enzymes is identical, both at pH 4 and 3. The titration curves of the two enzymes with immobilized antibodies are identical.

Glucosidases↗
PubMed1979

Purification and partial characterization of three forms of alpha-glucosidase from the fruit fly Drosophila melanogaster.

Three forms of alpha-glucosidase, I, II, and III, have been purified from the whole body extract of adult flies of Drosophila melanogaster in yields of 2.1, 5.3, and 6.7%, respectively. The purification procedures involved ammonium sulfate fractionation, Con A-Sepharose 4B affinity chromatography, DEAE-Sepharose CL-6B ion exchange chromatography, Sephacryl S-200 gel filtration, and preparative gel electrophoresis. Each purified enzyme showed a single band on polyacrylamide gel on both protein and enzyme activity staining. The molecular weights of alpha-glucosidases I, II, and III were estimated to be 200,000, 56,000, and 76,000, respectively, by gel filtration. SDS gels indicated that alpha-glucosidases II and III were each composed of a single polypeptide chain, whereas alpha-glucosidase I was composed of two identical subunits. Both alpha-glucosidases II and III hydrolyzed sucrose and p-nitrophenyl-alpha-D-glucoside (PNPG), but alpha-glucosidase I hydrolyzed PNPG to a much lesser extent than sucrose. For sucrose the pH optima of alpha-glucosidases I, II, and III were pH 6.0, 5.0, and 6.0 and the Km values were 13.1, 8.9, and 10 mM, respectively. For PNPG the pH optima of alpha-glucosidases II and III were pH 5.5 and 6.5 and the Km values were 0.77 and 0.21 mM, respectively.

Animals↗
PubMed1978

Characterization of the molecular defect in infantile and adult acid alpha-glucosidase deficiency fibroblasts.

Different clinical expressions of acid alpha-glucosidase deficiency have been described. The present study was undertaken to investigate the basic metabolic defect in the infantile and adult forms of the disease. Acid alpha-glucosidase (EC 3.2.1.20) was purified from normal and from adult acid alpha-glucosidase deficiency fibroblasts. The pH optimum; Michaelis constant; electrophoretic mobility in starch; thermal denaturation at pH 4.0 and 7.0; and inhibition by turanose, alpha-methylglucoside and trehalose were the same in purified enzyme from normal and mutant cells. Placental acid alpha-glucosidase was purified to, or near, homogeneity. Monospecific antibodies raised against the enzyme in each of three enzyme peaks obtained from the last purification step were found to cross-react with the enzyme of all three peaks, and with purified, normal fibroblast enzyme. Cross-reacting material (CRM) also was identified in fibroblast lysates from normal subjects and from both forms of acid alpha-glucosidase deficiency. The amount of CRM in the adult form appeared to be significantly less than in normal cells or cells from the infantile form. Enzyme activity was demonstrated in the immune complexes of the normal and adult acid alpha-glucosidase deficiency fibroblasts, but not of the infantile form. Competition for antibody binding sites was observed between normal and both types of mutant enzymes. The findings indicate that this case of infantile acid alpha-glucosidase deficiency is the result of a structural gene mutation which causes the synthesis of a catalytically inactive (CRM-positive) enzyme protein. It appears that in the adult form, the mutation causes a reduction in the amount of the enzyme protein present in the cells.

Adult↗
PubMed1976

Isolation and characterization of beta-glucosidase from the cytosol of rat kidney cortex.

A procedure is described for the preparation of extensively purified beta-D-glucosidase (EC 3.2.1.21) from the cytosol fraction of rat kidney. The specific activity of the beta-glucosidase in the high speed supernatant (100 000 X g, 90 min) fraction of rat kidney homogenate is 700-fold greater than that in the same fraction from heart, skeletal muscle, lung, spleen, brain or liver. beta-Glucosidase activity co-chromatographs with beta-D-galactosidase, beta-D-fucosidase, alpha-L-arabinosidase and beta-D-xylosidase activities through the last four column steps of the purification and their specific activities are 0.26, 0.39, 0.028 and 0.017 relative to that of beta-glucosidase, respectively. The specific activity of the apparently homogeneous beta-glucosidase is 115 000 nmol of glucose released from 4-methylumbelliferyl-beta-D-glucopyranoside per mg protein per h. All five glycosidase activities possess similar pH dependency (pH optimum, 6--7) and heat lability, and co-migrate on polyacrylamide disc gels at pH 8.9 (RF, 0.67). beta-Glucosidase acitivity is inhibited competitively by glucono-(1 leads to 5)-lactone (KI, 0.61 mM) and non-competitively by a variety of sulfhydryl reagents including N-ethylmaleimide, p-chloromercuribenzoate, 5,5'-dithio-bis(2-nitrobenzoic acid), and iodoacetic acid. Although the enzyme will release glucose from p-nitrophenyl and 4-methylumbelliferyl derivatives of beta-D-glucose, it will not hydrolyze xylosyl-O-serine, beta-D-glucocerebroside, lactose, galactosylovalbumin or trehalose. The enzyme consists of a single polypeptide chain with a molecular weight of 50 000--58 000, has a sedimentation coefficient of 4.41 S and contains a relatively large number of acidic amino acids. A study of the distribution of beta-glucosidase activity in various regions of the dissected rat kidney indicates that the enzyme is probably contained in cells of the proximal convoluted tubule. The enzyme is also present in relatively large amounts in the villus cells, but not crypt cells, of the intestine. The physiological substrate and function of the enzyme are unknown.

Amino Acids↗
PubMed1978

alpha-Glucosidase, a membrane-bound enzyme of alpha-glucan metabolism in Bacillus amyloliquefaciens. Purification and partial characterization.

The organism Bacillus amyloliquefaciens is capable of producing alpha-amylase (1,4-alpha-D-glucan glucanohydrolase, EC 3.2.1.1) and isoamylase (glycogen 6-glucanohydrolase, EC 3.2.1.68) extracellurlarly and a membrane-bound, intracellular alpha-glucosidase (alpha-D-glucoside glucohydrolase, EC 3.2.1.20). The amounts of alpha-glucosidase in cells of B. amyloliquefaciens grown on amylaceous polysaccharides were significantly higher then in cells grown on non-carbohydrate carbon sources. alpha-Glucosidase was exclusively found associated with membranes from ruptured spheroplasts by subcellular fractionation and solubilization studies. Salt solutions and chelating agents alone did not dislodge alpha-glucosidase from membranes, but in combination with detergents were most effective in solubilizing active enzyme (0.1% sodium cholate (pH 8.0)/0.4 M sodium chloride). Purified alpha-glucosidase very rapidly hydrolized p-nitrophenyl alpha-D-glucopyranoside and sucrose. Maltose, maltotriose, isomaltose and isomaltotriose were hydrolized at slower rates, whereas beta-glucosides and polymeric alpha-glucans were not attacked. Other properties of the purified enzyme were as follows: Temperature optimum for catalysis = 39 +/- 1 degrees C; pH optimum = 6.8; molecular weight = 27,000 +/- 1000. alpha-Glucosidase is proposed to function in the endogenous metabolism of alpha-glucans provided extracellularly as carbon sources for growth of B. amyloliquefaciens.

Bacillus↗
PubMed1979

Genetics of type II glycogenosis: assignment of the human gene for acid alpha-glucosidase to chromosome 17.

We have studied somatic cell hybrids between thymidine kinase (EC 2.7.1.75) deficient mouse cells and human diploid fibroblasts for the expression of human acid alpha-glucosidase (EC 3.2.1.20). A deficiency in this enzyme is associated with the type II glycogenosis or Pompe disease. All 30 somatic cell hybrids selected in hypoxanthine/aminopterin/thymidine medium expressed human acid alpha-glucosidase and galactokinase (EC 2.7.1.6) and retained human chromosome 17; counterselection of the same hybrids in medium containing 5-bromodeoxyuridine resulted in the growth of hybrids that concordantly lost the expression of human acid alpha-glucosidase and galactokinase as well as human chromosome 17. Hybrids between thymidine kinase-deficient mouse cells and fibroblasts from a patient with Pompe disease that contained human chromosome 17 were found not to express human acid alpha-glucosidase. Because we have already shown that hybrids between mouse peritoneal macrophages and GM54VA simian virus 40-transformed human cells selectively retain human chromosome 17 and lose all other human chromosomes, we tested 13 independent mouse macrophage x GM54VA hybrid clones, including two that retained human chromosome 17 and no other human chromosomes, for the expression of human acid alpha-glucosidase and galactokinase. All 13 hybrid clones were found to express these human enzymes. Thus, we conclude that the gene coding for human acid alpha-glucosidase is located on human chromosome 17.

Animals↗
PubMed1977

[beta-Glucosidases from fungus Geotrichum candidum].

beta-Glucosidases from Geotrichum candidum 3C cellulase preparation were separated from C1 enzymes and beta-1,4-glucanases by means of DEAE-Sephadex A-50 chromatography, gel filtration through P-150 Biogel and chromatography on CM-cellulose, and then were fractionated by isoelectric focusing using carrier ampholites with pH ranges 3-6 and 4-6. beta-Glucosidases with pI 3.8, 4.2, 4.6, 5.1, 5.6 and 6.2 were found in cellulase preparation from G. candidum 3C. Molecular weight of beta-glucosidases with pI 3.8, 4.2, 4.6 and 6.2, isolated under isoelectric focusing, were estimated by means of gel filtration through Sephadex G-200 to be 35000, 123000, 188000 and 223000 respectively. beta-Glucosidases with pI 3.8, 4.6, 5.6 and 6.2 hydrolyzed cellobiose and did not attack p-nitrophenyl-beta-D-glucopyranoside; those with pI 4.2 and 5.6 hydrolyzed p-nitrophenyl-beta-D-glucopyranoside and plant glucoside, protodioscin, and did not split cellobiose. All the beta-glucosidases studied did not hydrolyze laminaribose, beta-D-methylsylopyranoside, alder O-methylglucuronoxylane, o-nitrophenyl-beta-D-galactopyranoside and p-nitrophenyl-alpha-D-glucopyranoside. beta-Cellobiase with pI 6.2 hydrolzed lactoses, cellobioses with pI 3.8 and pI 5.6 splited gentiobiose. beta-Glucosidase with pI 4.6 did not attack any substrate studied, except cellobiose.

Cellulase↗
PubMed1979

Neutral alpha-glucosidase from human kidney. Molecular and immunological properties. Relationship with intestinal glucoamylase.

Some molecular properties of the purified neutral alpha-glucosidase from human kidney were studied. The enzyme is a glycoprotein with high molecular weight (315000-352000 according to the method used). Its sedimentation coefficient is 12.9S. It exhibits at least three peaks of activity in isoelectric focusing experiments. This heterogeneity appears to be related to sialic acid residues from the carbohydrate moiety. An anti-human renal alpha-glucosidase antiserum was raised from rabbit. The antiserum effect on human intestinal maltases was studied in immunodiffusion experiments. An identity pattern was observed between renal neutral alpha-glucosidase and intestinal glucoamylase. No precipitation occurred with intestinal sucrase. Renal neutral alpha-glucosidase and intestinal glucoamylase were both completely precipitated by the antiserum, their maltase activity being only slightly inhibited in the antigen-antibody complex. From their molecular and immunological properties a large homology appears between human renal alpha-glucosidase and intestinal glycoamylase.

Glucan 1,4-alpha-Glucosidase↗
PubMed1979

Studies on the possible identity of particulate beta-glucosidase and beta-xylosidase of mouse liver.

Mouse liver beta-glucosidase (beta-D-glucosidase glucohydrolase, EC 3.2.1.21) and beta-xylosidase (1,4-beta-D-xylan xylohydrolase, EC 3.2.1.37) activities were studied under different conditions of incubation in an attempt to determine whether these two activities are due to a single enzyme or two separate enzymes. The results showed that: (a) Particle-bound beta-glucosidase and beta-xylosidase activities exhibit similar characteristics with different buffers and at various pH values, in the presence or absence of taurocholate. (b) Both activities are inhibited by gluconolactone and conduritol B eposice. beta-Glucosidase activity is inhibited competitively by the two inhibitors, but beta-xylosidase activity is inhibited non-competitively. (c) Xylonolactone was a very poor inhibitor of both activities, but the inhibition of beta-xylosidase activity was more pronounced than that of beta-glucosidase. (d) The presence of glucosides or xylosides simultaneously in the incubation medium suggested the presence of one enzyme with both activities. These results, together with the mode of inhibition produced by gluconolactone and conduritol B epoxide also suggest the presence of two different binding sites for the beta-D-glucoside and beta-D-xyloside, respectively.

Animals↗
PubMed1978

Separation of acid and neutral alpha-glucosidase isoenzymes from fetal and adult tissues, cultivated fibroblasts and amniotic fluid cells by DEAE-cellulose and sephadex G-100 column chromatography.

Isoenzymes of alpha-glucosidases (EC 3.2.1.20) from various human organs and body fluids from fetuses and adults were separated by DEAE-cellulose column chromatography and gel filtration using Sephadex G-100. A minicolumn (0.35 X 2.5 cm) was used for the DEAE-cellulose column chromatography of extracts from tissues as well as cultivated cells of skin fibroblasts and amniotic fluid. The enzyme activity in the eluates was measured by the use of a methylumbelliferyl derivative as substrate and a very sensitive Microscope fluorimeter. In most tissue samples alpha-glucosidase was eluted mainly as a single peak when monitored at acid pH and as two peaks when the activity was measured at neutral pH in both columns. Another small peak representing alpha-glucosidase was found in fresh extracts of cultured cells on DEAE-cellulose columns. Neutral alpha-glucosidase especially in fibroblasts was extremely sensitive to storage at -20 degrees C. DEAE-cellulose column chromatography of plasma and amniotic fluid showed similar elution patterns of alpha-glucosidase. Differences were noticed in the elution pattern of urine from infants and adults. The tissue distribution and the different characteristics of the enzyme in samples of various origins and ages were discussed.

Adult↗
PubMed1978

Characterization of beta-glucosidase isoenzymes possibly involved in lignification from chick pea (Cicer arietinum L.) cell suspension cultures.

Crude cell wall preparations from Cicer arietinum L. cell suspension cultures show high activity for the hydrolysis of coniferyl alcohol beta-D-glucoside (coniferin). Various beta-glucosidase activities could be solubilized from these preparations by 0.5 M NaCl treatment and one of these could be shown to possess a high activity for the hydrolysis of coniferin. The enzyme activities were purified to near homogeneity by Sephadex G-200 and CM-Sephadex chromatography. Isoelectric focussing indicated the occurrence of beta-glucosidase isoenzymes with identical catalytic activity (pI 8.5-10). Molecular weights were determined as 110 000, with two subunits of 63 000 and 43 000. Maximum hydrolytic activity is at pH 5. The beta-glucosidase isoenzymes catalyze the hydrolysis of various beta-glucosides with aromatic aglycone structure and different sugar moieties. However, coniferin has been found to be one of the best substrates (km = 0.8 mM; V = 6 mumol.min-1.mg protein-1) for these beta-glucosidase isoenzymes. The data suggest that beta-glucosidase-catalyzed reaction might be involved in lignification of these plant cell cultures.

Cinnamates↗
PubMed1978

Properties of beta-glucosidase in cultured skin fibroblasts from controls and patients with Gaucher disease.

Membrane-bound beta-glucosidase from cultured skin fibroblasts can be solubilized in an active form by treatment of membrane preparations with a mixture of Triton X-100 and sodium taurocholate. Several properties of the solubilized enzyme have been studied in fibroblasts from normal, healthy individuals and from 14 patients with different clinical forms of Gaucher disease. The patients studied were classified as follows: group 1 consisted of 10 chronic patients, all (with one exception) of Ashkenazi Jewish origin; group 2 consisted of three black American patients with severe visceral symptoms, manifest from early childhood, but with no apparent neurological involvement; and group 3 consisted of a single white patient with the classical infantile form of the disease. Specific beta-glucosidase activity ranged from 6.6% to 16.5% mean control value in group 1 patients and from 4.1% to 5.8% in groups 2 and 3. When compared with the enzyme from control fibroblasts, the enzyme from chronic Gaucher patients (group 1) was more rapidly inactivated at 50 degrees C, had an altered pH curve, was less effectively inhibited by deoxycorticosterone-beta-glucoside, and was more effectively inhibited by deoxycorticosterone. The enzyme from patients in groups 2 and 3 was qualitatively indistinguishable from the control enzyme in terms of these parameters. No differences in Km (4-methylumbelliferyl-beta-glucoside) or sedimentation coefficient were found between the beta-glucosidases from control and Gaucher cells. The results demonstrate that cells from Ashkenazi Jewish patients with the chronic form of Gaucher disease contain a structurally altered form of beta-glucosidase. This enzyme differs both from normal beta-glucosidase and from the residual enzyme in patients of different ethnic origin and with clinically more severe forms of the disease.

Adolescent↗
PubMed1975

Inhibition of human liver beta-galactosidases and beta-glucosidase by n-bromoacetyl-beta-D-galactosylamine.

N-Bromoacetyl-beta-D-galactosylamine is an irreversible inhibitor of the 'acid' and the 'neutral' beta-galactosidases (beta-D-galactoside galactohydrolase, EC 3.2.1.23) of human liver. The inactivation of acid beta-galactosidase appears to involve a group with a pKa = 4.5. The inhibition of neutral beta-galactosidase only occurs above pH 8.0. Both enzymes are protected against inhibition by the presence of substrates, suggesting that the inhibitor reacts with the active site of the enzymes. Other lysosomal hydrolases are not inhibited by N-bromoacetyl-beta-D-galactosylamine, with the exception of 'neutral' beta-glucosidase (beta-D-glucoside glucohydrolase, EC 3.2.1.21). The pH dependence of neutral beta-glucosidase inactivation is essentially identical to that of the neutral beta-galactosidase. Inhibition of beta-glucosidase by this galactose derivative suggests that the same enzyme may bind glucosides and galactosides. Furthermore, both neutral beta-galactosidase and beta-glucosidase are inactivated at 52 degrees C with a half-life of 7.5 min. The presence of a single enzyme with both beta-glucosidase and beta-galactosidase activities is also supported by mixed-substrate experiments.

Acetylgalactosamine↗