Enzyme snail

Characterization of the enzymatic activity of the parasite and snail recombinant TPx are in progress, and the recombinant snail enzyme BgTPx has been found to be enzymatically active in an in vitro assay (Sayed and Williams, 2004). It remains to be seen whether the results obtained showing the transcript corresponding to BgTPx to be upregulated in parasite-exposed snails, compared to uninfected controls, correlates with enhanced thioredoxin peroxidase activity in infected snails. 

The removal of 30-35 % PolyPs from yeast cells during the lysis of cell walls by the snail enzyme was observed in Saccharomyces carlbergensis (Vagabov et al., 1973) - these were alkali-soluble fractions (Table 5.3). A comparative investigation of the amounts of various PolyP fractions was carried out in E. magnusii spheroplasts (Table 5.4.) and some sub-cellular fractions (Table 5.5). All of these data confirm the idea of PolyP localization in different compartments of cells of the lower eukaryotes. 

The Km values were estimated with respect to p-nitrophenyl /3-D-mannopyranoside, except for the snail enzyme, where phenyl /3-D-mannopyranoside was used. 

Lucerne enzyme lost 80 % of its activity in 3 hours at 45°. Snail enzyme was completely inactivated" in 30 minutes at 70°. 

Kerkut We have not as yet studied the mechanism of the loss of activity in the snail enzyme. The behavioural studies linked with AChE measurements indicate that activity returns to resting level after 24 h. 

Coleman RA, Ramchunder SJ, Moody AJ, Foggo A (2006) An enzyme in snail saliva induces herbivore-resistance in a marine alga. Func Ecol 21 101-106... 

Table II summarizes the results together with the detailed experimental conditions. As is evident, metabolic activities were detectable in these 3 aquatic species, but the rate was far lower as compared with mammalian hepatic enzume preparations, and the oxidative activities in snail were particularly low although the possibility was not ruled out of the presence of inhibitors of mixed-function oxidases in the fractions. The O-demethylation reaction proceeds extremely slowly in the enzyme preparation of aquatic animals, at less than one hundredth that of mammals.

Gastropods (snails), echinoderms (sea urchins and sea stars) and annelids (lugworms) were exposed to oil saturated sediments and assayed for AHH activity (17). Sediment was mixed with Venezuelan crude at a concentration of 0.2-0.5% and exposures were for one week (4°C) in a static system with water renewal at 2-3 day intervals. The aim was to determine if oil soaked sediments could induce AHH activity in some representative intertidal benthic organisms common to the subarctic waters of the North West Atlantic. Digestive gland homogenates from snails, sea urchins, and sea stars and a combination of intestinal and gill tissues from annelids were used in the enzyme assays. 

Enzyme Treatment. There are a number of enzymes which hydrolyze the microbial cell wall constituents. Enzymes exhibiting these activities include lysozyme, enzyme from snail extract and lytic enzyme systems of microbial origin composed of proteases,... 

AMP aminohydrolase, an enzyme relatively specific for AMP, has been observed in reptiles (44), erythrocytes (38), snail (45), unfertilized fish eggs (46), invertebrates (47), a variety of mammalian tissues (20), and a particulate fraction of pea seeds (48). Evidence suggests that the frog muscle AMP aminohydrolase is located within or just beneath the sarcolemma (49). The rabbit skeletal and heart muscle enzymes were found in the cytoplasm and mitochondria (20, Jfi, 50, 51), while the enzyme of kidneys and gills of freshwater fish was located in the cytoplasmic fraction (52). The enzyme occurs in most areas of the rat (53) and rabbit brain (54). The nonspecific enzyme from several microbial sources deaminates adenosine triphosphate (ATP) and adenosine diphosphate (ADP) as well as AMP (see Section V). 

Barry114 isolated a disaccharide, laminaribiose, on the partial hydrolysis of laminarin by enzymes (digestive juice of the snail Helix pomatia or H. aspersa) or by acid (seven hours with N oxalic acid on the water-bath). He showed that this disaccharide consisted solely of D-glucose and considered it to be 3-j3-D-glucopyranosyl-D-glucopyranose (XXIX). 

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