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[Various properties of galactose oxidase from Fusarium graminearum IMV-F-1060 immobilized on aminoorganosilochromes].

Galactose oxidase preparations are obtained from Fusarium graminearum IMV-F-N 1060 immobilized on aminoorganosilochromes activated by cyanuron chloride and 2.4-toluylene diizocyanate. The immobilized preparations were studied for their selective action on different carbohydrate substrates and for the pH-medium dependence of the obtained preparation activity. Potassium ferricyanide is established to have an activating effect on the immobilized enzyme. It is shown that the immobilized galactose oxidase preparations may be used for the analysis of galactose and lactose.

Enzyme Activation↗
PubMed1982

A galactokinase of Mycobacterium sp. 279 galactose mutant.

A galactokinase and the other enzymes of a galactose catabolic pathway were found in Mycobacterium sp. 279 galactose mutant. The galactokinase was partially purified in a procedure involving ammonium sulfate precipitation, Sephadex G-100 filtration and DEAE-cellulose chromatography. The enzyme was 170-fold purified with 25% of recovery. It was most active at pH 7.8-8.0 in the presence of Mg2+, CO2+, Mn2+ or Fe2+ ions. The molecular weight of the enzyme as determined by Sephadex G-100 filtration amounted to 41,700. The apparent Michaelis constants for galactose and ATP in spectrophotometric test were 1.0 mM and 0.29 mM, respectively. Mercuric compounds at concentration of 0.4 mM completely blocked the enzyme. The galactokinase was quite stable during storage at moderatory temperatures and neutral pH but underwent rapid inactivation on heating above 50 degrees C.

Ammonium Sulfate↗
PubMed1984

[Effect of carrageenan, galactose and 2,4-dinitrophenol on leukocyte phagocytosis of Staphylococcus aureus and E. coli].

The influence of carrageenan (0.1, 0.05 and 0.01%), galactose (1 X 10(-1), 1 X 10(-2) and 5 X 10(-2) mol/l) and 2,4-dinitrophenol (5 X 10(-4), 1 X 10(-4), 5 X 10(-5) and 1 X 10(-5) mol/l) on the phagocytosis of Staphylococcus aureus SG 511 and E. coli 04/K31 by polymorphonuclear neutrophil granulocytes was studied. At the same time the capacity of the germs to grow and multiply in presence of different concentrations of the analysed compounds was tested. The phagocytosis of Staphylococcus aureus SG 511 was not inhibited by carrageenan, galactose and 2,4-dinitrophenol, but an influence on the phagocytosis of E. coli 04/K31 could be clearly demonstrated (0.1 and 0.05% carrageenan, 1 X 10(-1) mol/l galactose, 5 X 10(-4) and 1 X 10(-4) mol/l 2,4-dinitrophenol). The multiplication of Staphylococci and E. coli was not influenced by all three compounds.

2,4-Dinitrophenol↗
PubMed1983

Thermodynamics of the binding of L-arabinose and of D-galactose to the L-arabinose-binding protein of Escherichia coli.

The thermodynamics of the binding of L-arabinose and of D-galactose to the L-arabinose-binding protein of Escherichia coli have been studied by isothermal and scanning calorimetry. The binding reaction with arabinose is characterized by an enthalpy change of -15.3 +/- 0.5 kcal mol-1 at 25 degrees C, and a large decrease in apparent heat capacity, amounting to -0.44 +/- 0.05 kcal K-1 mol-1, which is constant over the temperature range 8 to 30 degrees C. Very similar results were obtained with D-galactose. These calorimetric results have been combined with binding constants determined by equilibrium dialysis (Clark, A. F., Gerken, T. A., and Hogg, R. W. (1982) Biochemistry 21, 2227-2233) to obtain free energy and entropy changes over the range 5 to 30 degrees C, and by extrapolation to 60 degrees C. The protein undergoes reversible unfolding on being heated with an increase in enthalpy at 53.5 degrees C of 151.8 +/- 1.1 kcal mol-1 (169.2 +/- 1.2 kcal mol-1 at 59.0 degrees C) and in apparent heat capacity of 3.16 +/- 0.07 kcal K-1 mol-1. In the presence of arabinose, the unfolding enthalpy is increased to 200.7 +/- 1.8 kcal mol-1 at 59.0 degrees C, the increase being due to the enthalpy of dissociation of the ligand which amounts to 31 kcal mol-1 at the unfolding temperature. The unfolding temperature is increased by the presence of excess arabinose or galactose, an effect which is due solely to displacement by the added ligand of the unfolding-dissociation equilibrium. The thermodynamic data are discussed in connection with the detailed structural information available for this system from x-ray crystallography (Newcomer, M. E., Gilliland, G. L. and Quiocho, F. A. (1981) J. Biol. Chem. 256, 13213-13217, and references cited therein).

Arabinose↗
PubMed1984

[Transmural flow of D-galactose in the jejunum of young rats using a new perfusion chamber].

The chamber used allows the simultaneous but separated incubation of two intestinal segments (approximately 4 cm in length) in vitro and is especially suited for its application to studies on young animals. Segments are perfused with the help of a peristaltic pump (6 ml/h) without recycling. D-galactose fluxes across rat jejunum have been studied in everted jejunal segments from 19-21 day-old rats. Transmural fluxes (JmsGal) were determined using four external mucosal galactose concentrations (0.2, 2, 10 and 20 mM). The ratios of passive JmsGal were 1 : 11 : 49.7 : 96.7. Those due to active transport of the substrate were 1 : 7.1 : 14.6 : 18.8, indicating saturation. The active component of total JmsGal fluxes was 80%, 72%, 54% and 44%, respectively. Comparison of transmural galactose fluxes in noneverted segments from 20 day-old (suckling) and 25 day-old rats, showed that there is a marked reduction in both passive and active components of substrate flux across the intestine at the time of weaning.

Animals↗
PubMed1983

Effect of abdominal irradiation on the kinetic parameters of intestinal uptake of glucose, galactose, leucine, and gly-leucine in the rat.

A previously validated in vitro technique was used to determine the effect of abdominal irradiation on the intestinal uptake (Jd) of glucose, galactose, leucine, and gly-leucine in the rat. Three days after 600 rads from a cesium-137 source, there was a rise in the jejunal maximal transport rate (Jdm) and the apparent Michaelis constant (Km*) but a decline in the apparent passive permeability coefficient (Pd*) for glucose. Thereafter, there was a progressive decline in Km* and Jdm but a rise in Pd* for glucose uptake. In the ileum, irradiation was associated with an increased Km* and Jdm and a decreased Pd*. Fourteen days after 600 rads, Jd of leucine into the jejunum was unchanged but Jd of leucine into the ileum was increased because of a higher Pd*. The Jd of leucine from gly-leucine was greater than from leucine alone. The Jd of 0.5 to 10 mM gly-leucine into the jejunum was increased after 600 rads, whereas the greater Jd of gly-leucine into the ileum after irradiation was most marked at 40 mM. Fourteen days after 300 rads, the Jd of glucose and galactose was increased into the ileum, whereas the Jd of leucine was decreased and the Jd of these probes into the jejunum and colon was unchanged; 14 days after 900 rads, the Jd of glucose and galactose was unchanged in each site and the Jd of leucine was reduced in the ileum but not the jejunum or colon.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed1983

[Clinico-statistical evaluation of the simultaneous clearance of sulfobromophthalein and galactose in chronic liver diseases].

Sulfobromophthalein dye test and galactose tolerance test were performed, using both substances simultaneous i.v. injection, in 48 subjects with chronic persistent hepatitis, chronic active hepatitis and liver cirrhosis (with and without ascites). As control group 10 normal subjects were tested. Sulfobromophthalein excretion constant ( K1BSF ) drawn from the first part of the retention curve, and the galactose excretion constant (K Gal) were considered. The following conclusions were obtained: a) K1 BSF and K Gal are well-correlated; b) K1 BSF appears more sensitive for a whole evaluation of liver involvement, in absence of evident jaundice (total serum bilirubin less than 6 mg/100 ml); c) K Gal is less reliable in presence of ascites because of the artificial increase in galactose plasmatic clearance provoked by the substance passage to the effusion fluid; d) the statistical analysis using discrimining function methods makes possible a better distinction among the various kinds of liver diseases; e) the same type of statistical analysis shows a difference between cirrhotics with ascites responding to medical therapy in comparison to treatment- resistent ascites. This fact may account for a different level of hepatic functional activity.

Galactose↗
PubMed1981

An alpha-D-galactosyltransferase activity in Ehrlich ascites tumor cells. Biosynthesis and characterization of a trisaccharide (alpha-D-galactose-(1 goes to 3)-N-acetyllactosamine).

An alpha-D-galactosyltransferase activity has been detected in membranous fractions (42,000 x g) of Ehrlich ascites cells which transfers galactosyl groups from UDP-galactose to endogenous and exogenous acceptors. The products of the reaction contain alpha-D-galactopyranosyl groups at the nonreducing termini. A solid state assay was developed to follow alpha-D-galactosyltransferase activity in the presence of beta-D-galactosyltransferase. Examination of a variety of insolubilized exogenous acceptors indicated that the most active acceptors for the alpha-D-galactosyltransferase had the structure beta-D-Gal-(1 goes to 4)-beta-D-GlcNAc(1 goes to at their nonreducing termini. Incubation of UDP-[14C]galactose and beta-D-gal-(1 goes to 4)-D-GlcNAc (N-acetyllactosamine) or of UDP-galactose and beta-D-[14C]Gal-(1 goes to 4)-D-GlcNAc in the presence of the alpha-D-galactosyltransferase resulted in the enzymic synthesis of a 14C-labeled trisaccharide. Chemical and enzymic methods of analysis revealed the structure of the trisaccharide to be alpha-D-Gal-(1 goes to 3)-beta-D-Gal-(1 goes to 4)-D-GlcNAc. These data indicate that the alpha-D-galactosyltransferase in Ehrlich ascites cells transfers galactosyl groups to suitable acceptors to form an alpha-(1 goes to 3)-D-galactosidic linkage.

Animals↗
PubMed1981

The amino acid sequence of the D-galactose-binding protein from Escherichia coli B/r.

The complete primary structure of the Escherichia coli B/r galactose-binding protein was determined by the automated sequencing of fragments produced by cleavage with cyanogen bromide, o-iodosobenzoic acid, limited trypsin digestion, mild acid hydrolysis, and Staphylococcus aureus strain V8 protease. The protein, which has 309 amino acids, is notable in the extent to which it differs from the L-arabinose-binding protein. Comparison of these two proteins indicates only about 18% homology despite the close structural resemblence of the molecules which they bind. The galactose-binding protein is the chemoreceptor initiating chemotaxis toward galactose, and it thus becomes the first protein component required for chemotaxis for which the primary structure is known. GM 24602

Amino Acid Sequence↗
PubMed1981

[Sepsis due to E. coli in newborns with galactose intolerance (author's transl)].

The authors report on a case of sepsis due to E. coli in a newborn baby with galactose intolerance. The immature immunological state of the newborn child in combination with a disorder of galactose metabolism obviously favour the development of bacterial infections. Galactose-free formulas should be applied quickly together with an adequate antibiotic therapy in the case of newborn babies with suspected bacterial infection. The prognosis may be influenced favourably by early clarification of the cause of severe impairment including jaundice, vomiting, loss of weight and somnolence in the first three weeks of life.

Anti-Bacterial Agents↗
PubMed1982

First-order clearance of plasma galactose: the effect of liver disease.

Galactose clearance kinetics at plasma concentrations of 0.01-0.1 mg/ml were studied during continuous infusion of 25-100 mg D-galactose per minute. In 10 subjects, plasma galactose vs. time curves during 140-min infusion, and 60 min thereafter, showed the data to fit a single-compartment model and attain 95% of plasma steady state by 80 min. Doubling the infusion rate in 14 subjects resulted in an 8% reduction in clearance at the higher rate. Hepatic extraction in normal subjects was 94%, while in cirrhotics it was 79%. Day-to-day reproducibility in 11 subjects gave a coefficient of variation of 4.5%. Extrahepatic clearance showed 2% of the total to occur in the urine, and 2.3% to occur by erythrocyte metabolism. The overall mean (+/-SD) clearance in the normal subjects of 1378 +/- 218 ml/min was significantly (p less than 0.05) greater than for the stable cirrhotics at 918 +/- 279 ml/min, but not significantly different from patients with acute hepatocellular damage at 1186 +/- 300 ml/min. This index gives flow-dependent hepatic clearance, and provides a noninvasive measure of effective liver blood flow.

Erythrocytes↗
PubMed1982

[Intestinal malabsorption of glucose and galactose. Study of a family].

A girl with congenital glucose-galactose malabsorption and her two parents were studied. Hydrogen breath tests performed on the child during glucose and galactose tolerance tests (0.5 g/kg) were positive (increase in expired pH concentration of 21 p.p.m. and 32.5 p.p.m. from the basal level respectively). This was negative for fructose (2 g/kg). In vitro intestinal transport studies showed: 1) a selective decrease in active glucose accumulation (intracellular concentration 0.34 mM in 0.1 mM glucose bathing solution - controls: 1.58 +/- 0.56 (means +/- SD), and 12.1 mM in 10 mM bathing solution - controls: 38.4 +/- 12.4). 2) absence of net glucose absorption during in vitro Ussing chamber measurements with a marked decrease in mucosal membrane glucose permeability. For the parents, the hydrogen breath test was negative after glucose and galactose ingestion (2 g/kg) and intestinal transport was normal (father; intracellular concentration 1.32 mM and mother 2.04 for 0.1 mM bathing glucose concentration). The marked decrease in brush border permeability explains the absence of net glucose absorption in the child. The parents who are presumed to be heterozygotes did not exhibit any detectable transport defect.

Adult↗
PubMed1981

Uptake of galactose, ouabain and taurocholate into centrilobular and periportal enriched hepatocyte subpopulations.

Rat hepatocytes were isolated by a collagenase perfusion technique with subsequent subfractionation on Metrizamide gradients into subpopulations which have been designated band I and band II and are likely to be enriched with centrilobular and periportal cells, respectively. Band I was found to have a higher concentration of 5'-nucleotidase and band II a higher concentration of alcohol dehydrogenase. Furthermore, pretreatment of rats with phenobarbital led to higher cytochrome P-450 in the band I (centrilobular enriched) as compared to the band II (periportal enriched) subpopulations of hepatocytes. These data support their ascribed lobular origins. The uptake of a single concentration of galactose, ouabain and taurocholate into each of the two subpopulations was investigated until the concentration within the hepatocytes no longer increased. No difference was found in the uptake of [14C]galactose (25 mM) between the two hepatocyte subpopulations. However, the uptake of [3H]ouabain (125 microM) was greater in the centrilobular as compared to periportal enriched fraction of the hepatocytes. An even greater difference was found for the uptake of [3H]taurocholate (25 microM). The kinetics of taurocholate uptake were subsequently investigated. The Km for each subpopulation was 21 microM, while the Vmax of the centrilobular enriched fraction was 2.03 and that of the periportal enriched fraction was 1.57 nmol/min/mg of protein. These results show that there is a difference in uptake into hepatocytes of centrilobular and periportal origin for ouabain and taurocholate, but not for galactose.

Animals↗
PubMed1980

Effect of glipentide on galactose absorption and disaccharidase activity in rat small intestine.

The effect of hypoglycemic sulfonylurea glipentide on galactose transport and disaccharidase activity has been studied in rat small intestine. When 2 x 10(-4) M glipentide is present in the mucosal bathing solution, galactose active transport is inhibited 30% both in vivo and in vitro. Treatment of rats with 5 mg/kg glipentide p.o. for 10 days does not modify galactose absorption of disaccharidase activity. Incubation of the enzymes with glipentide shows no direct effect of the drug on its hydrolytic activity. The effects of glipentide on sugar transport are slight, or non significant in maintaining low blood sugar levels.

Animals↗
PubMed1981

The use of galactose oxidase in lipid labeling.

Galactose oxidase can be used to oxidize the terminal carbon atom of lipids containing galactose or N-acetylgalactosamine, and the resultant aldehyde group can be reduced back to the original carbinol with radioactive borohydride. The efficiency of the first reaction has been investigated systematically by using [6-3H]galactosyl ceramide as substrate and measuring the amount of radioactive water formed. This enabled us to establish that the addition of catalase and peroxidase greatly speeded the oxidation, that phosphate and PIPES buffers were the best among those tested, that the reaction continued for 24 hr without a second addition of galactose oxidase, and that the optimum concentration of organic solvent (tetrahydrofuran) was 50%. The suggestion if made that a similar set of variables be studied for each lipid or nonlipid by the same basic technique: labeling by the oxidase/borohydride method and use of the resultant compound as substrate.

Catalase↗
PubMed1994

Effect of lindane on galactose and leucine transport in chicken enterocytes.

Lindane (gamma-hexachlorocyclohexane) influence on the in vitro intestinal transport of D-galactose and L-leucine has been studied in isolated chicken enterocytes. Animals were injected i.p. with 30 mg/kg b.w. of the pesticide over 7 days. Total uptake of D-galactose and L-leucine was significantly decreased by lindane action. There was no alteration in the non-mediated component, but the mediated transport was markedly inhibited in both cases. Furthermore, the exit of D-galactose across the basolateral membrane, as well as (Na(+)-K+)-ATPase activity, was significantly decreased in pesticide-treated chickens.

Animals↗
PubMed1995

Murine granulocytic cell adhesion to bone marrow hemonectin is mediated by mannose and galactose.

Hemonectin (HN) is a bone marrow (BM) protein that promotes specific attachment of immature granulocytes and their precursors within the BM. We report that HN is a glycoprotein containing both mannose and galactose residues, and provide evidence that these carbohydrates mediate granulocytic cell adhesion to HN. Carbohydrate structure was determined by digoxigenin-conjugated lectin binding to HN and indicated the presence of mannose, galactose, sialic acid, and the absence of fucose-linked oligosaccharides. The role of carbohydrates in mediating cell adhesion was examined by chemical and enzymatic deglycosylation. Deglycosylation of HN with trifluoromethanesulfonic acid, which cleaves N- and O-linked oligosaccharides, inhibits 66% of cell attachment to HN, and results in an apparent decrease in molecular weight from 60 to 50 kD. Enzymatic deglycosylation with endo-B-N-acetylglucosaminidase H, which hydrolyzes specific N-linked mannose residues, inhibits 30% of cell adhesion to HN. Finally, the role of these specific sugars in hemonectin-mediated cell adhesion was confirmed with neoglycoprotein blocking. Preincubation of BM cells with mannosyl- and galactosyl-BSA probes produces a dose-dependent inhibition of cell attachment to HN, whereas fucosyl-BSA does not inhibit cell adhesion to HN. These results show that mannose and galactose partially mediate adhesion of BM granulocytes to HN.

Animals↗
PubMed1994

[Laser Raman spectrometry study on experimental galactose-induced cataract].

In order to observe the dynamic changes of hydration in galactose induced cataract, laser Raman spectrometry was used to study the water-content of lens nuclear of Wistar rats after fed them on galactose by 3, 7, 9, 11 and 17 days. The results showed that, (1) during the formation of cataract, the ratio of I3390/I2935 increased from 0.31 (3 days) to 2.26 (17 days). The water content in the nuclear was significantly increased. (2) the hydration of lens nuclear could be divided into two phases. The ratio of I3390/I2935 was increased slowly and steadily by 11 days after galactose feeding. Then, the ratio turned to increase quite fast till 17 days. It indicates that the hydration of nuclear is changed simultaneously with the formation of cataract.

Animals↗