Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using lectin staining methods in combination with exo- and endo-glycosidase digestion procedures, we analyzed the chemical structure of different types of blood group-related substances in serous cells of formalin-fixed, paraffin-embedded human submandibular glands. Serous cells produced only H antigen; A and B antigens were not present, and the expression of H antigen is dependent on the secretor status of the tissue donor. Although reactivity with Ulex europaeus agglutinin I (UEA-I) was not markedly reduced by alpha-L-fucosidase digestion, an affinity for peanut agglutinin (PNA) was seen after fucosidase digestion in the cells from secretors. In those from nonsecretors, no PNA reactivity appeared after enzyme digestion. On the other hand, sialidase digestion elicited PNA reactivity in serous cells irrespective of the donor's secretor status. PNA reactivity observed after fucosidase or sialidase digestion was susceptible to endo-alpha-N-acetylgalactosaminidase (endo-GalNAc-dase) digestion. SBA reactivity in UEA-I-negative cells from secretors, or in cells from fetuses and newborn infants, was markedly reduced by beta-galactosidase digestion. After galactosidase digestion, reactivity with Griffonia simplicifolia agglutinin II (GSA-II) appeared in the corresponding cells. This GSA-II reactivity was almost completely eliminated by subsequent beta-N-acetylhexosaminidase digestion. Whereas PNA reactivity in these cells was not reduced by beta-galactosidase treatment, it was significantly diminished by endo-GalNAc-dase digestion. These results suggest that at least two kinds of precursor disaccharides are produced in submandibular serous cells, i.e., SBA-reactive D-galactose-(beta 1-3,4)-N-acetyl-D-glucosamine and PNA-reactive D-galactose-(beta 1-3)-N-acetyl-D-galactosamine alpha 1-serine or threonine (O-glycosidically linked Type 3 chain or T antigen). Final fucosylation and synthesis of these two types of precursor chain appear to be under the control of the secretor gene.
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PMID:Histochemical analysis of the chemical structure of blood group-related carbohydrate chains in serous cells of human submandibular glands using lectin staining and glycosidase digestion. 249 20

The role of N-acetylneuraminic acid and N-acetyl-D-glucosamine containing molecules in vesicular stomatitis virus-cell interaction was studied using specific lectins (limulin and wheat germ agglutinin) and esoglycosidases (neuraminidase, beta-galactosidase, alpha-mannosidase, alpha-fucosidase, beta-N-acetyl-D-glucosaminidase). Lectin treatment of vesicular stomatitis virus (VSV) indicated that carbohydrates of the VSV G envelope glycoprotein were not required for virus infectivity, whereas sialic acid appeared directly involved in the attachment of virus to erythrocytes. The comparative results obtained after enzymatic digestion of cell membrane carbohydrates or their cross linking by lectins demonstrated that whereas VSV infectivity was strongly reduced by pretreatment of chick embryo cells, virus binding to erythrocytes was unaffected by such treatments. We conclude that sugar residues may participate at the host cell attachment site which differs, at least in part, from the membrane binding site of erythrocytes.
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PMID:Involvement of carbohydrates in vesicular stomatitis virus-cell early interaction. 257 93

Adler and Martin (1983, Curr. Eye Res. 2, 359-66) found cathepsin D to be present in crude preparations of bovine interphotoreceptor matrix (IPM). The purpose of the present study was to determine, by investigating several acid hydrolases in purer IPM samples, whether hydrolytic enzymes abundant in RPE lysosomes were present also as normal components of the IPM. IPM was prepared from bovine eyes by the introduction of a small bleb of buffer between the neural retina and the RPE. These IPM samples were free from significant contamination by surrounding tissues; they contained IRBP as their only major protein, and had negligible amounts of lactate dehydrogenase and ROS-specific proteins. Most acid hydrolases were assayed fluorometrically by measuring the 4-methylumbelliferone released upon hydrolysis of appropriate derivatives; the substrate for cathepsin was hemoglobin. The amounts of the enzymes found in the IPM were far from uniform and could not be correlated with enzyme activities in either RPE or retina homogenates. The hydrolases in the IPM varied in amount from beta-galactosidase (28% of the RPE level), through N-acetyl-beta-glucosaminidase (20%), alpha-fucosidase (15%), beta-glucuronidase (12%), alpha-glucosidase (8%), cathepsin D (7%), alpha-mannosidase (7%), down to beta-glucosidase, acid phosphatase, and acid lipase (trace amounts, less than 1%). These results agree with the relative amounts of enzymes found by Wilcox (1987) to be secreted into the medium by cultured human RPE cells. Furthermore, the rank order of hydrolases in the IPM is the same as that for hydrolases secreted (but not recaptured) by human fibroblasts in I-cell disease. The conclusion from these correlations is that lysosomal enzymes are probably secreted, as a normal process, by the RPE into the IPM, where they may have a role in digesting shed outer segments and in catabolizing IPM components.
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PMID:Selective presence of acid hydrolases in the interphotoreceptor matrix. 261 85

This work is part of an investigation into G. I. mucin susceptibility to enzyme degradation in normal and disease states. Formalin-fixed/paraffin embedded foetal (14-23 weeks) and neonatal colonic tissue was stained for mucins (neutral, N- and O-acylated sialomucins and sulphomucins) and PNA, UEA1, and Limax flavus. Enzymes tested: neuraminidases, alpha- and beta-galactosidase (E. coli and B. testis), beta-N-acetyl-glucosaminidase, alpha-fucosidase, single or in sequence, with and without prior neuraminidase treatment and followed by the stains. Acid mucins predominate throughout foetal life, sulphation occurs at 14 weeks and O-acylated sialomucins at 23 weeks. PNA and UEA1 are seen in traces or not detected. The mucin profile at birth is similar to the adult. Colonic mucins are susceptible to neuraminidase which abolishes Limax staining. The glycosidases effect on PNA is seen only with prior neuraminidase treatment and is particularly marked with beta-Gal(BT) in Neu----beta-Gal----beta-N-AcetylGlc than with beta-Gal (EC). Fucosidase with prior neuraminidase treatment has effect on UEA1 (decreases) and PNA (increases) affinities. Neuraminidase is essential as a first step in the process and by using beta-galactosidases EC and BT it was possible to show different PNA binding affinities. Preliminary data demonstrate the feasibility of this histochemical approach to the study of colonic mucins and forms the basis for further studies in the adult.
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PMID:Goblet cell mucin in human foetal colon, its composition and susceptibility to enzyme degradation: a histochemical study. 264 9

Sites of binding of eight different lectins (LTA, UEA I, WGA, SBA, DBA, CON A, PNA, RCA I) to cat submandibular gland were studied after exposure of tissue sections to sialidase, alpha-fucosidase, beta-galactosidase, alpha-mannosidase, beta-N-acetylglucosaminidase. All lectins were affected by enzymatic predigestion and the labeling of individual lectins was highly dependent upon the glycosidase used to pretreat the sections. Glycoconjugates of demilunar, acinar and ductal cells exhibited a different composition of terminal sequences. For example, fucose proved to form the disaccharide fucose-galactose in demilunar and acinar cells, whereas it was present with the sequence fucose-N-acetyl-D-glucosamine in striated duct cells. Sialic acid participated both to the terminal sequence sialic acid-galactose and sialic acid-N-acetyl-D-galactosamine either in demilunar or in ductal cells. Lectin labeling combined with glycosidase digestion was also helpful in verifying the influence of neighbouring oligosaccharides on the affinity of lectins for the respective sugars.
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PMID:Enzymatic degradation and quantitative lectin labeling for characterizing glycoconjugates which act as lectin acceptors in cat submandibular gland. 271 45

Lamellar body hydrolases in acutely damaged and regenerating type II cells were determined using an established rat model with well-defined stages of bronchiolo-alveolar injury and repair. Lamellar bodies were isolated from control and ozone-exposed (3.0 ppm for 8 hours) adult male rats by sucrose density gradient centrifugation and analyzed for their content of six different lysosomal hydrolases. Immediately after 3 ppm ozone exposure (zero-time) there was a significant decrease in specific enzyme activity (units/mg protein) of five lamellar body hydrolases and these activities remained depressed for at least 24 hours after exposure. In addition, total enzyme activity (units/lung) was reduced at zero-time for beta-hexosaminidase and at 24 hours postexposure for alpha-mannosidase and alpha-L-fucosidase. During the reparative and recovery stages (48 to 96 hours) the hydrolases demonstrated variable elevations in both specific activity and total activity (units/lung). Characteristically, beta-hexosaminidase and beta-galactosidase reached supranormal values at 96 hours, whereas alpha-mannosidase remained below normal levels through the recovery stage. Moreover, at 24 to 48 hours the lamellar body fraction demonstrated prominent enzyme depletion relative to the expanding pool of stored surfactant. It is concluded that acute ozone stress initiates the development of hydrolase deficiency within the lamellar bodies of injured and regenerating type II cells. This deficiency state is followed by asynchronous lamellar body hydrolase elevations that reflect distinct patterns of response rather than uniform return to normal condition. The lysosomal enzyme changes of lamellar bodies may be pathogenetically linked to the development of associated alterations in the storage and secretion of surfactant.
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PMID:Sequential changes of lamellar body hydrolases during ozone-induced alveolar injury and repair. 271 79

The possible occurrence of circadian and circannual rhythms in the plasma concentrations of the following enzymes of lysosomal origin was assessed: beta-D-N-acetylglucosaminidase (EC 3.2.1.30) beta-D-glucuronidase (EC 3.2.1.31), beta-D-glucosidase (EC 3.2.1.21), beta-D-galactosidase (EC 3.2.1.22), alpha-D-galactosidase (EC 3.2.1.23), alpha-L-fucosidase (EC 3.2.1) and alpha-D-mannosidase (EC 3.2.1.24). The circadian rhythm was studied in 16 women (aged: 17-24 years) and 13 men (age: 23 years) volunteers; the circannual rhythm, in 10 women and 8 men (age: 20-25 years). The circadian rhythm was detected in all the tested enzymes of women, and only in alpha-D-galactosidase, beta-D-glucosidase, alpha-D-mannosidase and beta-D-acetylglucosaminidase of men. A statistically significant difference between genders in the circadian rhythm was exhibited by beta-D-galactosidase (MESOR; amplitude) beta-D-glucosidase (MESOR; amplitude; acrophase) beta-D-N-acetylglucosaminidase, beta-D-glucuronidase and alpha-D-galactosidase (MESOR) and alpha-L-fucosidase (amplitude, acrophase). A circannual rhythm was detected in all the tested enzymes with the exception of beta-D-glucuronidase and beta-D-N-acetylglucosaminidase; no statistically significant difference between genders was detected. The group rhythms of some of the enzymes (alpha-D-galactosidase, beta-D-glucosidase, beta-D-galactosidase) showed similar values of both circadian and circannual acrophases, suggesting that they may subjected as a group to the same chronobiological coordination, possibly mediated by hormones. The chronobiological rhythms of lysosomal enzymes were different from those of lactate dehydrogenase and alpha 1-antitrypsin, indicating that these rhythms are not merely reflecting fluctuations of the water content of plasma. No in-phase relationship was observed between the circadian and circannual rhythms of plasma cortisol and those of the tested lysosomal enzymes, excluding a direct chronobiological and possibly functional relationship between this hormone and lysosomal enzymes.
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PMID:Chronobiological study of several enzymes of lysosomal origin in human plasma. 278 34

Quantitative comparisons of the time course of biochemical and morphological changes induced by peroxisome proliferators resulting in low and high incidences of hepatic cancer have not been conducted previously under bioassay conditions. [4-Chloro-6-(2,3-xylidino)-2-pyrimidyl-thio]acetic acid (Wy-14,643) at 0.1% in the diet produced a much higher incidence of hepatic cancer in male rats than 1.2% di(2-ethylhexyl)phthalate (DEHP) in the diet. Both diets, however, caused similar degrees of peroxisome proliferation. To investigate this difference in carcinogenicity, H2O2-detoxification mechanisms and indices of oxidative damage were evaluated in male F-344 rats fed 1.2% DEHP or 0.1% Wy-14,643 for up to one year. DEHP or Wy-14,643 treatment increased hepatic catalase activity approximately 25% from 8 to 365 days. DEHP or Wy-14,643 treatment decreased hepatic glutathione peroxidase activity by 50% from 8 to 365 days. Glutathione concentrations were not affected by 151 days of DEHP or Wy-14,643 feeding. The similar effects of DEHP and Wy on H2O2 detoxification enzymes and glutathione concentrations suggests that these factors are not responsible for the widely different carcinogenicities of Wy-14,643 and DEHP. Hepatic vitamin E concentrations were 50% lower in rats receiving Wy-14,643 for 151 days as compared to rats fed DEHP or control diets. Lipofuscin, which was contained within lysosomes, was increased 3-fold after 39 days of DEHP and remained at this level up to 365 days of treatment. In comparison, lipofuscin was increased 4-fold after 18 days of Wy-14,643 and continued to accumulate in a linear manner reaching values 30-fold over controls after 365 days of treatment. DEHP treatment for 39-365 days increased the activities of the lysosomal enzymes alpha-fucosidase, beta-galactosidase and N-acetylglucosaminidase 50-100%. The same enzyme activities were increased approximately 4-fold after 39-365 days of Wy-14,643. Lysosomal cathepsin B activity was unchanged by DEHP but doubled by 151 and 365 days of Wy-14,643. Acid phosphatase activity was unchanged by DEHP but increased by 50% after 151 and 365 days of Wy-14,643. In addition, conjugated dienes were increased (approximately 45%) only in rats receiving Wy-14,643 for 151 and 365 days. These data show for the first time that the magnitude and time course of lipofuscin deposition, induction of lysosomal enzymes and conjugated diene accumulation, is correlated closely with the degree of carcinogenicity. Wy-14,643-induced decreases in hepatic vitamin E concentrations could contribute to the observed accumulation of conjugated dienes at later time points.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Relationship of oxidative damage to the hepatocarcinogenicity of the peroxisome proliferators di(2-ethylhexyl)phthalate and Wy-14,643. 292 96

Upon detergent or hypo-osmotic lysis of CHO-cell postnuclear supernatants or isolated lysosomes at pH 4.8, the lysosomal enzymes beta-hexosaminidase, beta-galactosidase, alpha-fucosidase and cathepsin C were readily pelleted, whereas the exogenous marker, long-term-internalized horseradish peroxidase, was not. Salt or pH elevation greatly decreased lysosomal-enzyme pelletability. The results suggest that, under native conditions, lysosomal hydrolases may be aggregated. Aggregation could promote enzyme retention within the organelle.
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PMID:Effects of pH, detergent and salt on aggregation of Chinese-hamster-ovary-cell lysosomal enzymes. 296 75

Four glycosidases (beta-galactosidase, alpha-mannosidase, alpha-fucosidase and beta-N-acetylglucosaminidase) were studied in chicken normal and regenerating liver, in turkey poult liver and in virus induced avian tumors--chicken hepatoma (strain Mc-29), Rous sarcoma (strain Schmidt-Ruppin) and turkey poult hemocytoblastoma nodules (strain Mc-31). The multiple forms of beta-N-acetylglucosaminidase were assayed as well. A particular enzyme pattern was found in the tumor lines under investigation. A characteristic property of hepatoma cells was the elevation of beta-galactosidase activity and of the former enzyme and that of beta-N-acetylglucosaminidase for the hemocytoblastoma. In Rous sarcoma the glycosidase activities (except that of alpha-fucosidase) were much lower, compared to the other two solid tumors. All enzyme activities were compared with those in the normal liver of the corresponding avian species, and with the liver of tumor bearing fowls and with regenerating chicken liver. Unlike the rat liver in the avian normal and tumor tissues the percentual ratio between the multiple forms A and B of beta-N-acetylglucosaminidase was found to be 30:70%.
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PMID:Glycosidases in normal and regenerating chicken liver, hepatoma Mc-29, Rous sarcoma, in turkey poult liver and hemocytoblastomes, provoked by the leukosis virus strain Mc-31. 298 24


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