Digestive Glycosidases Research Articles

Digestive glycosidases from cannonball jellyfish (Stomolophus sp. 2): identification and temporal-spatial variability.

Jellyfish are economically important organisms in diverse countries, carnivorous organisms that consume various prey (crustaceans, mollusks, bivalves, etc.) and dissolved carbohydrates in marine waters. This study was focused on detecting and quantifying the activity of digestive glycosidases from the cannonball jellyfish (Stomolophus sp. 2) to understand carbohydrate digestion and its temporal-spatial variation. Twenty-three jellyfish gastric pouches were collected in 2015 and 2016 in the Gulf of California in three localities (Las Guásimas, Hermosillo, and Caborca). Nine samples were in intra-localities from Las Guásimas. Chitinase (Ch), β-glucosidase (β-glu), and β-N-acetylhexosaminidase (β-NAHA) were detected in the gastric pouches. However, cellulase, exoglucanase, α-amylase, polygalacturonase, xylanase, and κ-carrageenase were undetected. Detected enzymes showed halotolerant glycolytic activity (i = 0-4 M NaCl), optimal pH, and temperature at 5.0 and 30-50 °C, respectively. At least five β-glucosidase and two β-N-acetylhexosaminidase were detected using zymograms; however, the number of proteins with chitinase activity is not precise. The annual variation of cannonball jellyfish digestive glycosidases from Las Guásimas between 2015-2016 does not show significant differences despite the difference in phytoplankton measured as chlorophyll α (1.9 and 3.4 mg/m3, respectively). In the inter-localities, the glycosidase activity was statistically different in all localities, except for β-N-acetylhexosaminidase activity between Caborca and Hermosillo (3,009.08 ± 87.95 and 3,101.81 ± 281.11 mU/g of the gastric pouch, respectively), with chlorophyll α concentrations of 2.6, 3.4 mg/m3, respectively. For intra-localities, the glycosidase activity did not show significant differences, with a mean chlorophyll α of 1.3 ± 0.1 mg/m3. These results suggest that digestive glycosidases from Stomolophus sp. 2 can hydrolyze several carbohydrates that may belong to their prey or carbohydrates dissolved in marine waters, with salinity over ≥ 0.6 M NaCl and diverse temperature (4-80 °C) conditions. Also, chlorophyll α is related to glycosidase activity in both seasons and inter-localities, except for chitinase activity in an intra-locality (Las Guásimas).

Long-Term Consequences of the Effect of Copper and an Electromagnetic Field on the Size and Weight Parameters and Activity of Digestive Glycosidases in Underyearlings of Roach Rutilus rutilus

Long-Term Consequences of the Effect of Copper and an Electromagnetic Field on the Size and Weight Parameters and Activity of Digestive Glycosidases in Underyearlings of Roach Rutilus rutilus

Effect of a Shift in Diurnal Geomagnetic Variation on the Activity and Sensitivity of Digestive Glycosidases in Roach Underyearlings to Heavy Metals

The effect of temporal shifts in diurnal geomagnetic variation with 6- and 12-h intervals relative to the day–night cycle on the activity of digestive glycosidases (maltase and amylolytic activity) and their sensitivity to the in vitro influence of heavy metal ions (Cu2+, Zn2+, Pb2+, Cd2+) at a concentration of 25 mg/L has been studied in roach Rutilus rutilus (L.) underyearlings. Amylolytic activity (the total activity of starch-hydrolyzing enzymes: α-amylase, glucoamylase, and maltase) is determined by the modified Nelson method, maltase activity by the glucoseoxidase method with a Fotoglukoza clinical biochemistry kit. It is found that exposing embryos to both 6- and 12-h shifts in diurnal geomagnetic variation reduces the activity of maltase and its sensitivity to the effect of zinc and cadmium ions. Amylolytic activity increases only in roach underyearlings exposed to a 6-h shift in diurnal geomagnetic variation as embryos. The sensitivity of starch-hydrolyzing enzymes to the influence of copper (6- and 12-h shifts) and cadmium (12-h shift) increases. The decrease in the enzyme activity and its increased sensitivity to the inhibitory effect of heavy metals may reduce the efficiency of carbohydrate hydrolysis in roach underyearlings. The increase in the amylolytic activity can be considered as adaptation of the digestive system of the fish to a 6-h shift in diurnal geomagnetic variation relative to the day–night cycle during embryogenesis.

Sensitivity of Digestive Glycosidases to Heavy Metals in Roach Rutilus rutilus (L.) Yearlings: The Consequences of Hypogeomagnetic Conditions During Early Ontogenesis

The effect of exposure to hypogeomagnetic conditions (HMCs) during roach Rutilus rutilus (L.) early development (embryos and prelarvae) on the activity of digestive glycosidase (maltase and amylolytic activity) and the in vitro sensitivity of the digestive glycosidase to ions of heavy metals (Cu²⁺, Zn²⁺, Cu²⁺ + Zn²⁺, Pb²⁺, Cd²⁺, and Pb²⁺ + Cd²⁺) in yearlings have been studied. The sensitivity of starch-hydrolyzing enzymes to all studied metals (at a concentration of 25 mg/L) and the sensitivity of maltase to Zn²⁺ and Pb²⁺ have increased in the fish preexposed to HMCs at stages of embryos or prelarvae. The sensitivity of maltase to Cd²⁺ and Pb²⁺ + Cd²⁺ has increased in the fish preexposed to HMCs only as embryos. The combined effects of Cu²⁺ and Zn²⁺ (1 : 1) or Pb²⁺ + Cd²⁺ (1 : 1) on the activity of intestinal glycosidases in the fish exposed to HMCs are less pronounced than the sum effects observed in separate tests with these ions.

Delayed effect of geomagnetic storm simulation on size, mass and activity of digestive glycosidases in roach (Rutilus rutilusLinnaeus, 1758) underyearlings

Delayed effect of geomagnetic storm simulation on size, mass and activity of digestive glycosidases in roach (<i>Rutilus rutilus</i>Linnaeus, 1758) underyearlings

The eggs of the apple snailPomacea maculataare defended by indigestible polysaccharides and toxic proteins

The freshwater snails Pomacea Perry, 1810 lay conspicuous aerial egg clutches that are ignored by most predators. Egg biochemical defenses in the apple snail Pomacea canaliculata (Lamarck, 1822) are provided by multifunctional proteins. We analyzed the eggs of a sympatric species, Pomacea maculata Perry, 1810, studying the gross composition, toxicity, hemagglutinating activity, and its antinutritive and antidigestive properties. Eggs are mostly composed of polysaccharides (mainly galactogen) and proteins, followed by lipids and nonsoluble calcium. Two perivitellins account for ∼85% dry mass of the egg protein. The major lipids are phospholipids and sterols. A suite of potential defenses was determined, including strong lethal neurotoxicity on mice and moderate antidigestive and lectin activities. Remarkably, their polysaccharides were refractive to in vitro digestion by digestive glycosidases. This study characterized ∼99% of egg composition and identified multiple potential defenses, provided not only by proteins but also by polysaccharides. This is the first evidence to our knowledge that reserve sugars may be involved in defenses, giving further insight into the unusual reproductive strategy of these well-defended snail eggs.

Effect of magnetic storm on the sensitivity of juvenile roach intestinal glycosidase to heavy metals (Cu, Zn) and the herbicide roundup

The effect of a magnetic storm (frequency range of 0–5 Hz) on the activity and sensitivity of underyearling intestinal glycosidase (maltase and amylolytic activity) to heavy metal ions (Cu2+ and Zn2+, concentrations of 0.1–25 mg/L) and the herbicide Roundup (0.1–50 µg/L) have been studied in vitro during early the embryogenesis of roach Rutilus rutilus (L.). The impact of the magnetic storm on roach embryos 48–72 h post fertilization increases the sensitivity of digestive glycosidases (except for maltase in the presence of Cu) to Cu, Zn, and Roundup.

Impact of simulated geomagnetic storm on activity of digestive glycosidases in roach Rutilus rutilus underyearlings

Long-term consequences of simulated geomagnetic storm action on early stages (0–24 h, 24–48 h, 48–72 h and 72–96 h post fertilization) of roach Rutilus rutilus embryogenesis were studied. The study revealed that fluctuations of magnetic field resulted in the decrease in the fish body length and weight, as well as in the differently directed changes in the activities of glycosidases (maltase, sucrase, and amylolytic activity) and kinetic characteristics of carbohydrates hydrolysis in the intestine of 4 month-old roach. The most pronounced changes in the fish body sizes were noted after exposure to magnetic field fluctuations within the time period of 48–72 h post fertilization. Relatively low values of Michaelis constant were revealed in the fish developed during embryonic stage either in the hypomagnetic conditions or under impact of simulated geomagnetic storm. This phenomenon may be considered as a response of fish digestive system to changes in the magnetic field during embryogenesis.

Characterization of intestinal digestive glycosidases in planktofagous and benthofagous fish species of the genus Ballerus (Cyprinidae)

The activity of hydrolases (maltase, sacharase, amylolytic activity) in the intestinal mucosa of the planktofagous blue bream Ballerus ballerus and benthofagous white-eye bream Ballerus sapa were investigated. The thermal characteristics of maltase hydrolysis (Topt and Eact) are similar in both species. The lower KM of maltase hydrolysis in the white-eye bream reflects a higher enzyme/substrate affinity and indicates a more effective carbohydrate hydrolysis in the bentho-versus planktofagous species. The glycosidase activity in the white-eye bream is twice as high as in the blue bream. This may be due not only to different feeding spectra and biochemical food composition but also to differencies in the thyroid status of species under consideration.

Effects of heavy metals (Cu and Zn) on digestive glycosidases in benthivorous fish of areas of Rybinsk Reservoir differing in anthropogenic loads

The separate and combined in vitro effects of heavy metal ions (Cu and Zn) at concentrations of 0.1–25 mg/L on the activities of maltase, sucrase, and amylolytic activity in the intestines of bream and roach caught in areas of the Rybinsk Reservoir differing in anthropogenic loads have been studied. In fish from the polluted Sheksninskii Reach, membrane maltase and sucrase enzymes are less sensitive to the effects of Cu and Zn ions than in fish from the relatively clean Volzhskii Reach. On the other hand, starch-hydrolyzing enzymes were more sensitive to the effects of the metals under study in bream from a polluted area, which was especially evident in summer. The combined effect of Cu and Zn ions (1: 1) in most cases weakens the separate effects of these metals on the activities of hydrolases (except for amylolytic activity) in the studied fish.

Effect of rate of increase of water temperature on sensitivity of fish digestive glycosidases to action of copper and zinc

There was established an increase of sensitivity of glycosidases of intestinal mucosa of juvenile goldfish Carassius auratus, carp Cyprinus carpio, roach Rutilus rutilus, and common perch Perca fluviatilis to action in vitro of heavy metal ions (copper and zinc at concentrations of 0.1–25 mg/l) at heating of water at the summer period. The inhibitory effect of copper and zinc ions as a rule was higher at the heating rate of 50°C/h than at the rate of 4°C/h. The perch glycosidases were less sensitive to the elevation of temperature and to effect of the copper ions as compared with the enzymes of the carp species.

PDX1 regulation of FABP1 and novel target genes in human intestinal epithelial Caco-2 cells

The transcription factor pancreatic and duodenal homeobox 1 (PDX1) plays an essential role in pancreatic development and in maintaining proper islet function via target gene regulation. Few intestinal PDX1 targets, however, have been described. We sought to define novel PDX1-regulated intestinal genes. Caco-2 human intestinal epithelial cells were engineered to overexpress PDX1 and gene expression profiles relative to control cells were assessed. Expression of 80 genes significantly increased while that of 49 genes significantly decreased more than 4-fold following PDX1 overexpression in differentiated Caco-2 cells. Analysis of the differentially regulated genes with known functional annotations revealed genes encoding transcription factors, growth factors, kinases, digestive glycosidases, nutrient transporters, nutrient binding proteins, and structural components. The gene for fatty acid binding protein 1, liver, FABP1, is repressed by PDX1 in Caco-2 cells. PDX1 overexpression in Caco-2 cells also results in repression of promoter activity driven by the 0.6kb FABP1 promoter. PDX1 regulation of promoter activity is consistent with the decrease in FABP1 RNA abundance resulting from PDX1 overexpression and identifies FABP1 as a candidate PDX1 target. PDX1 repression of FABP1, LCT, and SI suggests a role for PDX1 in patterning anterior intestinal development.

Polyhydroxylated alkaloids isolated from mulberry trees (Morusalba L.) and silkworms (Bombyx mori L.).

New polyhydroxylated alkaloids, (2R,3R,4R)-2-hydroxymethyl-3,4-dihydroxypyrrolidine-N-propionamide from the root bark of Morus alba L., and 4-O-alpha-D-galactopyranosyl-calystegine B(2) and 3 beta,6 beta-dihydroxynortropane from the fruits, were isolated by column chromatography using a variety of ion-exchange resins. Fifteen other polyhydroxylated alkaloids were also isolated. 1-Deoxynojirimycin, a potent alpha-glucosidase inhibitor, was concentrated 2.7-fold by silkworms feeding on mulberry leaves. Some alkaloids contained in mulberry leaves were potent inhibitors of mammalian digestive glycosidases but not inhibitors of silkworm midgut glycosidases, suggesting that the silkworm has enzymes specially adapted to enable it to feed on mulberry leaves. The possibility of preventing the onset of diabetes and obesity using natural dietary supplements containing 1-deoxynojirimycin and other alpha-glucosidase inhibitors in high concentration is of great potential interest.

Lutzomyia longipalpis:pH in the Gut, Digestive Glycosidases, and Some Speculations uponLeishmaniaDevelopment

Gontijo, N. F., Almeida-Silva, S., Costa, F. F., Mares-Guia, M. L., Williams, P., and Melo, M. N. 1998.Lutzomyia longipalpis:pH in the gut, digestive glycosidases, and some speculations uponLeishmaniadevelopment.Experimental Parasitology90, 212–219. Screening for digestive glycosidases in different parts of the gut and associated organs ofLutzomyia longipalpisis reported. Searches for the enzymes were made in blood-fed and non-blood-fed females and the enzymes were characterized as soluble or membrane-bound molecules. A total of four different activities were detected, corresponding to the following specificities: an α-glucosidase, anN-acetyl-β-d-glucosaminidase, anN-acetyl-β-d-galactosaminidase, and an α-l-fucosidase. Their possible role and importance forLeishmaniadevelopment are discussed and the α-glucosidase enzyme was partially characterized. The pH inside the gut of non-blood-fed phlebotomines was measured with pH indicator dyes. The pH ranges obtained for crop, midgut, and hindgut were, respectively, higher than pH 6, pH 6, and lower than pH 6. A hypothesis concerning these data andLeishmaniadevelopment is proposed.

Alkaloidal Glycosidase Inhibitors and Digestive Glycosidase Inhibition in Specialist and Generalist Herbivores of Omphalea diandra

Generalist herbivores of the neotropical liana Omphalea diandra (Euphorbiaceae) were compared to the specialist herbivore, larvae of the uraniid moth Urania fulgens, with respect to their ability to accumulate the alkaloidal glycosidase inhibitors (AGIs) produced by the plant and the resistance of their digestive glycosidases to inhibition by these AGIs. The generalist herbivores did not accumulate the AGI aglycones 2R,5R-dihydroxymethyl-3R,4R-dihydroxypyrrolidine (DMDP) and 2,6-dideoxy-2,6-imino-D-glycero-L-gulo-heptitol (HNJ) to the levels detected in larvae of U. fulgens, which contained 0.05–0.11% dry weight DMDP and 0.17–0.35% HNJ. Glucosides of DMDP and HNJ that were synthesized by O. diandra were either absent from both the generalist and the specialist herbivores or present at low levels (less than 0.01%), even though HNJ-glucoside was often the most abundant AGI in the foliage. Analyses of the herbivores' feces indicated that failure to accumulate AGIs was due to the compounds being metabolized rather than excreted. The digestive glycosidases of U. fulgens larvae were more resistant to inhibition by AGI aglycones than those of the generalist herbivores. Similarly, sucrose and maltose hydrolysis in two of the generalist lepidopteran herbivores, larvae of Panthiades ballus and Theope virgilius, was more resistant to inhibition by DMDP than in larvae of Spodoptera littoralis, a lepidopteran which does not encounter O. diandra in nature. There was little difference in the susceptibility to AGIs of glycosidases from the generalist coleopteran Rhabdopterus fulvipes, which naturally feeds on O. diandra, compared with the coleopteran Dermestes maculatus, which does not. The glucoside of HNJ was found to be a very potent inhibitor of trehalase activity in all the insects examined. AGIs are considered to reduce the nutritional value of O. diandra to nonadapted herbivores rather than be acutely toxic. Nevertheless, U. fulgens does appear to be unique among Omphalea-feeding insects in its ability to accumulate AGIs, suggesting that it gains some advantage from storing these compounds.

N-containing sugars from Morus alba and their glycosidase inhibitory activities

The reexamination of N-containing sugars from the roots of Morus alba by improved purification procedures led to the isolation of eighteen N-containing sugars, including seven that were isolated from the leaves of Morus bombycis. These N-containing sugars are 1-deoxynojirimycin ( 1), N-methyl-1-deoxynojirimycin ( 2), fagomine ( 3), 3- epi-fagomine ( 4), 1,4-dideoxy-1,4-imino-pD-arabinitol ( 5), 1,4-dideoxy-1,4-imino-pD-ribitol ( 6), calystegin B 2 (1α,2β,3α,4β-tetrahydroxy- nor-tropane, 7), calystegin C 1, (1α,2β,3α,6α-pentahydroxy- nor-tropane, 8), 1,4-dideoxy-1,4-imino-(2- O-β-pD-glucopyranosyl)- d-glucopyranosyl)- d-arabinitol ( 9), and nine glycosides of 1. These glycosides consist of 2- O- and 6- O-α- d-galactopyranosyl-1-deoxynojirimycins ( 10 and 11, respectively), 2- O-, 3- O- and 4- O-α- d-glucopyranosyl-1-deoxynojirimycins ( 12, 13, and 14, respectively), and 2- O-, 3- O-, 4- O- and 6- O-β- D-glucopyranosyl-1-deoxynojirimycins ( 15, 16, 17, and 18, respectively). Compound 4 is a new member of polyhydroxylated piperidine alkaloids, and the isolation of 6 is the first report of its natural occurrence. It has recently been found that the polyhydroxy- nor-tropane alkaloids possess potent glycosidase inhibitory activities. Calystegin A 3 is the trihydroxy- nor-tropane, and calystegins B 1 and B 2 are the tetrahydroxy- nor-tropane. Calystegin C 1, a new member of calystegins, is the first naturally occurring pentahydroxy- nor-tropane alkaloid. The inhibitory activities of these compounds are investigated against rat digestive glycosidases and various commercially available glycosidases.