Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:2.4.99.6 (sialyltransferase)
1,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A significant elevation of serum sialyltransferase and fucosyltransferase mean activities was observed in 19 untreated patients with multiple myeloma. However, sialyltransferase mean activity was significantly lower in 13 other patients treated for 1-30 months with alkylating drugs and prednisolone. Such a definite decrease in serum enzyme activity on treatment was not recorded for fucosyltransferase. Instead, this activity was significantly increased in treated patients as compared to controls. The presenting clinical features of the 32 patients with multiple myeloma were the basis for a clinical staging system with regard to myeloma cell burden according to established criteria. In untreated patients (as opposed to treated ones), a significantly higher serum sialyltransferase (but not fucosyltransferase) activity was obtained among those 11 belonging to stage III than among the other eight with stages I and II, suggesting a link between tumour burden and enzyme activity. This assumption was further strengthened in those six patients followed lengthwise with regard to serum sialyltransferase activity. Concomitantly with objective evidence of change in tumour burden they showed corresponding alterations in sialyltransferase activity. The determination of sialyltransferase and fucosyltransferase activity in serum may be an additional contribution to refine initial assessment and follow-up of individual patients with multiple myeloma.
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PMID:Serum sialyltransferase and fucosyltransferase activities in patients with multiple myeloma. 404 76

Membrane glycopeptides were examined in human colonic adenocarcinoma and normal colonic mucosa. The carbohydrates of membrane glycopeptides were found to be markedly reduced in tumor tissue and the relative proportions of the various sugars were altered. Although all of the sugars were lower in tumor tissue when compared to the adjacent normal mucosa, galactosamine, fucose, and sialic acid were more significantly reduced. Examination of the blood group activity and lectin-binding properties of membrane glycopeptides revealed that specific carbohydrate structures had changed in the tumor tissue. Most striking of these changes was the disappearance of glycoprotein-associated blood group A activity. Assay of the enzyme responsible for synthesis of the blood group A determinant showed that this glycosyltransferase activity was greatly diminished in tumor tissue. A galactosyltransferase and a fucosyltransferase were also significantly lower in the tumor tissue whereas the levels of another galactosyltransferase and a sialyltransferase were unaltered. Glycosidase activities in the normal and tumor tissues were similar. The results show that an alteration in glycoprotein biosynthesis occurred during tumorigenesis that resulted in a modified membrane glycoprotein composition and that these changes are probably a reflection of reduced levels of the enzymes responsible for glycoprotein synthesis.
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PMID:Alterations of membrane glycopeptides in human colonic adenocarcinoma. 414 May 12

Streptococcus pneumoniae infection leads to multifold increases in sialyltransferase, galactosyltransferase, alpha 2-fucosyltransferase, and alpha 3-fucosyltransferase activity of rat liver. Such changes may reflect an increased demand for glycosylation of acute-phase proteins synthesized and secreted by the liver during inflammatory processes. Serum sialyltransferase became elevated in bacteria-infected or burned rats and sandfly fever-infected humans, but did not correlate with acute-phase serum protein changes. These data suggest that nonparenchymal liver cells, such as macrophages, may contribute substantially to elevated sialyltransferase activity in the circulation during infection and, as such, represent a general host response to infection and tissue trauma.
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PMID:Elevated glycosyltransferase activities in infected or traumatized hosts: nonspecific response to inflammation. 615 10

Serum sialyltransferases and fucosyltransferases measured by an affinity adsorbent technique were studied in 27 exactly defined patients with malignant pulmonary diseases. Fourteen patients with benign pulmonary diseases and 56 with benign surgical diseases were used as controls. Enzyme activities were expressed as amounts of labeled precursor molecules incorporated into endogenous acceptors in counts per minute (cpm). The mean sialyltransferase activity was 583 cpm in bronchial carcinoma, 485 cpm in benign pulmonary disease and 428 cpm in benign surgical disease. The only statistically significant difference was between bronchial carcinoma and benign surgical disease. The mean fucosyltransferase activity was 813 cpm in bronchial carcinoma, 436 cpm in benign pulmonary disease and 255 cpm in benign surgical disease. All the differences were statistically significant. There were no statistically significant differences between the WHO histologic bronchial carcinoma groups. The correlation between sialyltransferase and fucosyltransferase activity in bronchial carcinoma was statistically significant (r = 0.59). In squamous cell carcinoma (N = 6), it was strongly significant (r = 0.96) and there was a significant correlation also in small cell carcinoma (N = 10; r = 0.79) but not in adenocarcinoma (N = 9; r = 0.30) and benign pulmonary disease (N = 14; r = 0.44). It is suggested that serum sialyltransferases and fucosyl transferases would not be decisive for diagnosis when used alone in bronchial carcinoma, but could be included in a screening test battery.
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PMID:Serum sialyltransferase and fucosyltransferase activities in patients with bronchial carcinoma. 631

We have assayed glycosyltransferase activities during the granulocytic and macrophage-like differentiation of human promyelocytic leukemia (HL-60) cells. Functional granulocytic differentiation was assayed by the decarboxylation of 2-deoxyglucose in addition to nitroblue tetrazolium reduction. Dimethylsulfoxide (DMSO) treated HL-60 cells, induced to granulocytic differentiation, had higher 2-deoxy-glucose decarboxylation activity, and contained less sialyltransferase (ST), more fucosyltransferase (FT), and more N-acetylglucosaminyltransferase (NGT) activities than untreated cells. HL-60 cells treated with another granulocytic differentiator, retinoic acid, also had higher 2-deoxyglucose decarboxylation activity, and contained less ST, more FT, and more NGT activities than untreated cells. In contrast, cells treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA) reported to differentiate HL-60 to macrophage-like cells, but did not show an increased level of 2-deoxyglucose decarboxylation activity, but contained more galactosyltransferase (GT) and FT activities as compared to untreated cells. These findings suggest that the alterations of glycosyltransferase levels during the differentiation of precursor cells may not depend upon different inducers, but are characteristic of the phenotypic expression of the mature cell type.
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PMID:Glycosyltransferase alterations are cell type related when human promyelocytic leukemia (HL-60) cells are treated with various inducers of differentiation. 641 38

The cell membrane fraction from c-ALL, B-ALL, Ph' + ALL, B-CLL, T-CLL, AML, blastic-CML, normal leukocytes, PHA-stimulated lymphocytes and several T, B and myeloid human leukemic cell lines has been used in different cell types to demonstrate different patterns of glycosyltransferase activity. Both B- and T-CLL cell membranes have low fucosyltransferase B and A activity compared to acute leukemias; while sialyltransferase activity is higher in B- than in T-CLL. AML cell membranes and ML-1 human myeloblast cell line membranes have exceptionally high fucosyltransferase A activity compared to all other leukemic cells or cell lines. Human leukemic B cell lines expressed cell membrane sialyltransferase, fucosyltransferase B and probably fucosyltransferase A activity several times higher than T cell lines. Human myeloid cell lines ML-1 and HL-60 express 5- to 20-fold higher galactosyltransferase activity than human leukemic T and B cell lines. Both sialyltransferase and galactosyltransferase activity were higher in all leukemic cells than in normal leukocytes and PHA-stimulated normal lymphocytes. This is the first study carried out on glycosyltransferases using cells obtained from leukemic patients characterized immunologically. These results indicate that all glycosyltransferase activity, with the exception of fucosyltransferase activity in CLL, were higher in leukemic cells than in normal cells. Moreover, large differences in these enzymes, e.g. very high galactosyltransferase activity in myeloid cell lines compared to B and T cell lines, of fucosyltransferase A in AML and myeloblast cell lines compared to all other cells, and of sialyltransferase in B-CLL or B cell lines compared to T-CLL or T cell lines, could be useful in characterizing certain leukemias and hematopoietic cell lines.
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PMID:Glycosyltransferase activities in leukemic cells from patients and human leukemic cell lines. 641 47

The mononuclear cells separated from human blood by Ficoll-Hypaque centrifugation contained and released sialyltransferase, galactosyltransferase, and fucosyltransferase. Granulocytes contained and released lesser amounts of glycosyltransferases, whereas platelets released more fucosyltransferase than sialyltransferase or galactosyltransferase. When mononuclear cells were incubated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), the release of these three glycosyltransferases increased two- to six-fold, and cell suspension glycosyltransferase activities decreased 10-50%. Mononuclear cells were fractionated into lymphocytes and monocytes using baby hamster kidney cells microexudate-coated flasks. TPA stimulated the release of glycosyltransferases from lymphocytes but not from monocytes. The release of glycosyltransferases by TPA-treated mononuclear cells was not further stimulated by reincubation with TPA and was not affected by puromycin, cAMP, or cGMP. Concanavalin A, a mitogenic stimulator of lymphocytes, also stimulated the release of glycosyltransferases from mononuclear cells, but to a lesser extent. TPA did not stimulate the release of 5'-nucleotidase or decrease its activity on the cell pellet. Triton X-100 (0.2%) stimulated the release of glycosyltransferases to the same extent as TPA, but also caused the release of 5'-nucleotidase. [(3)H]TPA bound specifically and reversibly to mononuclear cells. The possible relationship between glycosyltransferase release and TPA effect on the plasma membrane is discussed.
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PMID:12-O-tetradecanoyl-phorbol-13-acetate release of glycosyltransferases from human blood cells. 644 9

Multiple forms of microsomal and plasma membrane sialyl and fucosyltransferases from chicken liver and transplantable hepatoma Mc-29 have been separated by means of isoelectric focusing. A net different pattern was distinguished between liver and hepatoma microsomal and plasma-membrane associated transferases. Microsomal sialyltransferase from hepatoma Mc-29 has typical forms with pI = 5.69, 7.43, 8.05 and 8.56, while in plasma membrane, enzymes with pI = 5.00 and 8.70 occur. The presence of 9 forms of fucosyltransferase within the pH range 3.46-9.57 for hepatoma microsomes and within pH 4.52-9.60 for plasma membranes was detected. Forms with pI 5.10, 5.75 and 7.87 could be considered specific for the hepatoma microsomal enzyme, and forms with pI 4.52, 4.85 and 5.20 for the plasma-membrane associated enzyme.
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PMID:Multiple forms of chicken liver and hepatoma Mc-29 microsomal and plasma-membrane sialyl and fucosyltransferases. 653 16

L-Fucose and N-acetylneuraminic (sialic) acid occupy terminal positions on the oligosaccharide side-chains of human cervical mucin but the addition of both these monosaccharides to the same carbohydrate acceptor residue is kinetically unfavourable. The following evidence suggests that the levels of L-fucose are more sensitive to regulation than those of N-acetylneuraminic acid: (1) tissue levels of sialyltransferase (EC 2.4.99.1) activity are 20-30 times greater than those of fucosyltransferase (EC 2.4.1.68); (2) both glycosyltransferases are susceptible to inhibition by their nucleotide products but a comparison of the Ki and the apparent Km of these enzymes shows that modulation of fucosyltransferase is more probable; (3) Postsecretory removal of L-fucose from cervical mucin is probably due to the high levels of mucus-associated alpha-L-fucosidase. Furthermore the activity of this enzyme is probably modulated by the pH gradient within the cervix. Mucin glycosylation can be visualized by autoradiography using [3H]L-fucose applied to cervical explants in organ culture. Mucus production during this process is not sensitive to exogenous ovarian steroid hormones, though in other aspects the secretory process appears normal. It is proposed that the cyclicity of mucus rheology is not directly influenced by an action of these hormones on mucin synthesis or hydration.
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PMID:Terminal glycosylation in human cervical mucin. 656 36

In an effort to assess the effect of surface carbohydrates upon the metastasizing properties of tumor cells, lectin-resistant mouse melanoma cells were selected. Wheat-germ-agglutinin-resistant lines displayed mainly decreased metastasis properties as well as well-defined alterations in surface carbohydrates: in a glycopeptide with four side chains, two of them were missing their terminal sialic acid residues while two fucoses were newly attached to the oligosaccharide. The enzymatic defect could be pinpointed to an over-60-fold increase in fucosyltransferase, while the sialyltransferase did not decrease significantly. Revertants were again selected with lectins and their fucosyltransferase activities returned to normal values again. The metastasizing potential of the revertants was not yet assessed carefully but a return of some of the metastasizing potential was noted.
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PMID:The influence of membrane mutations on metastasis. 713 74


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