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

Watermelon fruit exhibit acute softening and placental-tissue water soaking following short exposure to exogenous ethylene. Experiments were performed to address transcript abundance and activities of cell wall and membrane hydrolases in placental tissue in response to treatment of watermelon fruit with ethylene. Watermelon fruit were harvested at immature and full-ripe stages and exposed to 50 microL L(-1) ethylene for 6 days at 20 degrees C. Ethylene affected the abundance of transcripts for PME (EC 3.2.1.11), and alpha-(EC 3.2.1.22) and beta-GAL (EC 3.2.1.23) but these effects were dependent on fruit maturity and appeared not to be associated with the water-soaking syndrome. PG (EC 3.2.1.15) and EXP mRNAs accumulated significantly in response to ethylene exposure. Additionally, the levels of mRNA and activities of LOX (EC 1.13.11.12), PLC (EC 3.1.4.3) and PLD (EC 3.1.4.4) were elevated in fruit of both maturity classes exposed to ethylene and were temporally associated with the visible symptoms of water soaking. The activity trends and transcript abundance in ethylene- compared with air-treated fruit indicate that PG, EXP, LOX, PLC and PLD levels increase with the onset and development of the water-soaking disorder and support the view that catabolic reactions targeting the membranes and cell-walls contribute to the disorder.
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PMID:Ethylene-induced gene expression, enzyme activities, and water soaking in immature and ripe watermelon (Citrullus lanatus) fruit. 1512 25

A study of galacto-oligosaccharides (GOS) synthesis from lactose with beta-galactosidase from Kluyveromyces lactis (Maxilact L2000) was carried out. The synthesis was performed using various initial lactose concentrations ranging from 220 to 400 mg/mL and enzyme concentrations ranging from 3 to 9 U/mL, and was investigated at 40 degrees C and pH 7, in a stirred-tank reactor. In the experimental range examined, the results showed the amount of GOS formed depended on lactose concentration but not on enzyme concentration. Galactose was a competitive inhibitor, while glucose was a non-competitive inhibitor. In a further study, a laboratory-scale reactor system, fitted with a 10-kDa NMWCO composite regenerated cellulose membrane, was used in a continuous process. The reactor was operated in cross-flow mode. The effect of operating pressures on flux and productivity was investigated by applying different transmembrane pressures to the system. The continuous process showed better production performance compared to the batch synthesis with the same lactose and enzyme concentrations at 40 degrees C, pH 7. Comparison of product structures from batch and continuous processes, analyzed by HPAE-PAD and methylation analysis, showed similarities but differed from the structures found in a commercial GOS product (Vivinal GOS).
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PMID:Synthesis of galacto-oligosaccharide from lactose using beta-galactosidase from Kluyveromyces lactis: Studies on batch and continuous UF membrane-fitted bioreactors. 1562 51

The intercoding regions between many Leishmania sp. genes regulate their mRNA expression. The MSPL mRNA, encoding a subclass of the major surface protease (MSP) of Leishmania chagasi, increases in abundance, when protein synthesis is arrested, while alpha-tubulin (alpha-TUB) mRNA and most other mRNAs do not. We found that the intercoding region between MSPL-coding regions, when cloned downstream of the beta-galactosidase reporter gene (beta-GAL), caused beta-GAL mRNA to increase 8- to 10-fold after inhibiting protein synthesis with cycloheximide. Stable L. chagasi transfectants containing hybrid MSPL/alpha-TUB intercoding regions cloned downstream of beta-GAL were made. The alpha-TUB intercoding region induced high-level baseline beta-GAL mRNA that increased only 1.3-fold after incubation with cycloheximide. In contrast, the MSPL intercoding region, as well as constructs containing nucleotides 303-505 from the MSPL 3'UTR, caused steady-state beta-GAL mRNA levels in the absence of cycloheximide that were approximately 10% of alpha-TUB constructs. These levels increased between 4.4- and 13.2-fold after cycloheximide was added. Constructs containing half of this region (303-394 or 395-505) produced intermediate levels of beta-GAL mRNA and intermediate levels of cycloheximide induction. The kinetics of cycloheximide induction of beta-GAL mRNA was similar with region 303-505 constructs as with constructs bearing the entire endogenous MSPL intercoding region. Furthermore, region 303-505 increased reporter mRNA abundance after cycloheximide by increasing mRNA half-life. Hence, we have identified a 202-nucleotide region within the MSPL 3'UTR that is in part responsible for cycloheximide induction. We hypothesize that this region may interact with labile regulatory protein factor(s).
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PMID:Regulation of genes encoding the major surface protease of Leishmania chagasi via mRNA stability. 1587 63

The intercoding regions of many Leishmania sp. genes have been implicated in the regulation of mRNA processing, stability, and translation. Herein we show that the intercoding region of the Leishmania chagasi alpha-tubulin gene (alpha-TUB) confers stable beta-galactosidase (beta-GAL) reporter mRNA levels during promastigote growth and development in vitro and during protein synthesis inhibition. The abundance of both endogenous alpha-TUB mRNA and beta-GAL mRNA from a beta-GAL coding region situated upstream of the alpha-TUB intercoding region did not change significantly as promastigotes grew from logarithmic to stationary phase in vitro and the half-life of the beta-GAL mRNA remained constant. The abundance of both the endogenous alpha-TUB and the beta-GAL mRNA increased by less than 2-fold after protein synthesis inhibition corresponding to a moderate increase in mRNA half-life. These data suggest that the alpha-TUB intercoding region is an excellent control for the study of the regulation of other differentially expressed genes.
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PMID:Leishmania chagasi: the alpha-tubulin intercoding region results in constant levels of mRNA abundance despite protein synthesis inhibition and growth state. 1588 91

The ability of Toxoplasma gondii to cycle between the tachyzoite and bradyzoite life stages in intermediate hosts is key to parasite survival and the pathogenesis of toxoplasmosis. Studies from a number of laboratories indicate that differentiation in T. gondii is a stress-induced phenomenon. The signalling pathways or molecular mechanisms that control formation of the latent bradyzoite stage are unknown and specific effectors of differentiation have not been identified. We engineered a reporter parasite to facilitate simultaneous comparison of differentiation and replication after various treatments. Chloramphenicol acetyltransferase (CAT), expressed constitutively from the alpha-tubulin promoter (TUB1), was used to quantitate parasite number. beta-galactosidase (beta-GAL), expressed from a bradyzoite specific promoter (BAG1), was used as a measure of bradyzoite gene expression. Sodium nitroprusside, a well-known inducer of bradyzoite differentiation, reduced reporter parasite replication and caused bradyzoite differentiation. Stress-induced differentiation in many other pathogens is regulated by cyclic nucleotide kinases. Specific inhibitors of the cAMP dependent protein kinase and apicomplexan cGMP dependent protein kinase inhibited replication and induced differentiation. The beta-GAL/CAT reporter parasite provides a method to quantify and compare agents that cause differentiation in T. gondii.
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PMID:Cyclic nucleotide kinases and tachyzoite-bradyzoite transition in Toxoplasma gondii. 1621 48

Activities of seven acid glycosidases: beta-N-acetylhexosaminidase (beta-HEX), alpha- and beta-galactosidase (alpha- and beta-GAL), alpha- and beta-mannosidase (alpha- and beta-MAN), alpha-glucosidase and alpha-fucosidase in magnum region of hen (Gallus gallus domesticus) oviduct, and four acid glycosidases: beta-HEX, beta-GAL, alpha- and beta-MAN in egg albumen, were investigated. beta-HEX from magnum and egg albumen hydrolysed 4-methylumbelliferyl-beta-N-acetylhexosamine-6-sulphate (4-MeUmbGlcNAc-6-SO(4)) like mammalian beta-HEX form A. Multiple forms of magnum and egg albumen beta-HEX, beta-GAL, alpha- and beta-MAN were separated by strong anion exchange chromatography and chromatofocusing method. Chromatofocusing of the magnum resulted in the appearance of multiple forms for beta-HEX with pI of 6.18, 5.43, 5.55, 5.34, 5.27 and 5.16, for beta-GAL with pI of 4.98, 4.84, 4.77, 4.64 and 4.68-4.63, for alpha-MAN with pI of >or=7.4, 6.75, 6.62 and 6.26, and for beta-MAN two forms with pI of 6.37 and 5.77. Chromatofocusing of egg albumen yields multiple forms for beta-HEX with pI of 6.24, 6.08, 5.55 and 5.35, for beta-GAL two forms with pI of 5.10 and 4.86-4.80 for alpha-MAN multiple forms with pI of >or=7.4, 6.80, 6.60 and 6.30, and for beta-MAN forms with pI of 6.30 and 5.77. In conclusion, this study was the first to show beta-HEX activity against 4-MeUmbGlcNAc-6-SO(4) in the magnum and albumen of bird eggs, corresponding to beta-HEX A activity in mammals. Main multiple forms of beta-HEX, beta-GAL, alpha- and beta-MAN occurring in the magnum were revealed in the egg albumen. Comparison with a cock of the same breed showed that hen egg magnum and albumen has the same multiple forms of the enzymes that are found in the epididymides and seminal plasma of the cock.
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PMID:Acid glycosidases from hen oviduct and egg albumen. 1623 36

Resistance or susceptibility of Red Kidney, Pinto and Small White beans (Phaseolus vulgaris) to the alpha, beta, and gamma strains of Colletotrichum lindemuthianum was either confirmed or established. These fungal strains secrete alpha-galactosidase, beta-galactosidase and beta-xylosidase when grown on cell walls isolated from the hypocotyls of any of the above bean varieties. These enzymes effectively degrade cell walls isolated from susceptible 5-day old hypocotyls but degrade only slightly the walls isolated from resistant 18-day old hypocotyls. The amounts of the beta-galactosidase and beta-xylosidase secreted by the 3 fungal strains are relatively low and are approximately equivalent. The secretion of these 2 enzymes is not dependent upon the bean variety from which the hypocotyl cell walls used as a carbon source were isolated. However, the fungal strains secrete greater amounts of alpha-galactosidase when grown on hypocotyl cell walls isolated from susceptible plants than when grown on walls from resistant plants. Virulent isolates of the fungus, when grown on hypocotyl cell walls isolated from a susceptible plant, secrete more alpha-galactosidase than do attenuated (avirulent) isolates of the same fungal strain grown under the same conditions. The alpha-galactosidase secreted by each of the fungal strains is capable of removing galactose from the hypocotyl cell walls of each bean variety tested. Galactose is removed from the cell walls of each variety at the same rate regardless of whether the cell walls were isolated from a susceptible or resistant plant.
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PMID:Host-Pathogen Interactions: I. A Correlation Between alpha-Galactosidase Production and Virulence. 1665 49

Studies showed that the plant cell wall polysaccharide arabinogalactan supported growth of Bifidobacterium longum in batch culture. Galactose was also utilized, but not arabinose, the other major constituent sugar of the polymer. Enzymes required for hydrolysis of arabinogalactan ('arabinogalactanase', alpha-arabinopyranosidase, beta-galactosidase) were inducible and cell-associated in B. longum, and their expression was repressed by glucose. Considerable amounts of alpha-arabinopyranosidase and beta-galactosidase were synthesized during growth on arabinogalactan, but only low levels of arabinogalactanase were detected. B. longum only grew on arabinogalactan in continuous culture under putative carbon-excess conditions. In C-limited chemostats, the bifidobacterium could not establish unless Bacteroides thetaiotaomicron was present in co-culture. The relationship between the two organisms was not simply commensal; at low specific growth rates, bacteroides cell population densities were approximately 30% lower than those recorded in axenic culture, indicating the existence of competitive interactions with the bifidobacterium. In contrast, at high specific growth rates, a mutualistic association was observed, in that Bact. thetaiotaomicron was maintained in the chemostats at high dilution rates if bifidobacteria were also present. Measurements of residual carbohydrate in spent culture fluid from C-limited chemostats indicated that a large part of the arabinogalactan molecule could not be broken down by either B. longum or Bact. thetaiotaomicron alone, or in co-culture. Formate and acetate were the major fermentation products of B. longum cultured in the presence of high concentrations of arabinogalactan, confirming that these bacteria were growing under energy-limited conditions.
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PMID:Arabinogalactan utilization in continuous cultures of Bifidobacterium longum: effect of co-culture with Bacteroides thetaiotaomicron. 1688 14

In this study specific activities of four acid glycosidases: beta-N-acethylhexosaminidase (beta-HEX), beta-galactosidase (beta-GAL), alpha- and beta-mannosidase (alpha- and beta-MAN) were investigated in Japanese quail testes and epididymides during posthatch development and regression after light reduction. The specific activity of testicular beta-HEX and beta-GAL increased steadily during posthatch development and assumed maximum values for testes weighing 200-400 mg, when numerous spermatocytes appear in the testes of quail, and then decreased slowly. These enzymes showed much higher specific activity after 15 days of light reduction, and decreased to the control level after 30 days. Activity of alpha- and beta-MAN remained rather constant during testicular development and involution. The epididymal activity of the acid glycosidases was very low in immature individuals, whereas in sexually mature birds it was found to increase several-fold. Short photoperiod resulted in a decreased activity of these enzymes after 30 days to the values found in immature birds. A marked increase in the activity of acid glycosidases in the epididymides of sexually mature animals and a decrease in this activity during epididymidal regression indicate that these enzymes take part in reproductive processes. It is concluded that the activities of beta-HEX, beta-GAL, alpha- and beta-MAN in the development and regression of Japanese quail testes and epididymides change similarly as in mammals.
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PMID:Changes in the activity of acid glycosidases during posthatch development and regression after light reduction of Japanese quail testes and epididymides. 1721 59

Chronic ear disease with cholesteatoma is characterized by an intrusion of keratinizing stratified squamous epithelium into the middle ear manifesting bone resorption at the interface of the perimatrix. The aim of our study was to investigate the markers of a catabolic process associated with several chronic inflammatory states. We assessed the level of catabolism of glycoconjugates in assays of cholesteatoma extracts, quantifying two lysosomal exoglycosidases: alpha-mannosidase (alpha-MAN) and beta-galactosidase (beta-GAL). Cholesteatomas (n = 15) and normal adult postauricular skin served as controls (n = 15) were collected from the patients during surgery owing to chronic otitis media. To assess exoglycosidase activity, release of p-nitrophenol from p-nitrophenol derivatives of alpha-mannose and beta-galactose was used. In 13 of 15 specimens, we observed significantly higher activity of investigated enzymes in cholesteatoma tissue compared with control tissue (postauricular skin). The mean activity of alpha-MAN from the cholesteatoma cells was 1.76 +/- 1.10 nkat/g wet tissue and 0.61 +/- 0.21 nkat/g wet tissue in the control probes. The mean activity of beta-GAL from the cholesteatoma cells was 1.77 +/- 1.07 nkat/g wet tissue and 0.87 +/- 0.20 nkat/g wet tissue in the control probes. Catabolic reactions involving glycoproteins, glycolipids, and proteoglycans may play a role in cholesteatoma-related bone resorption. The present data indicating that the lysosomal exoglycosidases alpha-MAN and beta-GAL are significantly and consistently elevated suggest the need to further correlations assessment between levels of alpha-MAN and beta-GAL and cholesteatoma behavior. Further research should also evaluate the relative importance of these particular exoglycosidases in manifesting bone resorption in considering the spectrum of identified inflammatory mediators.
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PMID:Catabolism of glycoconjugates in chronic otitis media with cholesteatoma. 1785 Jul 36


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