The activity of hydrolytic enzymes in the digestive system of Acanthobdellida, Branchiobdellida and Hirudinida (Annelida,Clitellata) – considerations on similarity and phylogeny

Activities of nineteen hydrolases were measured in the digestive systems of predatory and blood-feeding true leeches (Hirudinida) and their closest relatives, Branchiobdellida and Acanthobdellida. Hydrolase activities were analyzed in different parts of the digestive systems: the species-specific anterior part, i.e. jaws, pharynx or proboscis, crop and intestine. The results obtained suggest that food digestion and possible absorption predominate in the intestine of most of the studied Hirudinida and A. peledina, whereas in B. astaci these processes take place in the anterior part of the digestive system and crop. In Erpobdellidae and Piscicola respirans, the activity of acid and alkaline phosphatases, N-acetyl-β-glucosaminidase, leucine and valine arylamidases, and α-fucosidase was also detected in the anterior part of the digestive system. We also detected differences in enzyme occurrence between the studied species, which are probably connected with their different food preferences. Moreover, the presence of the whole spectrum of enzymes in predatory leeches and the absence of trypsin and α-chymotrypsin activity in the crop of all the leeches support the hypothesis that the leech ancestor was a blood-feeder. Our study showed that “Rhynchobdellida” constitute a paraphyletic group which confirms the previous results based on molecular phylogenetics, while Arhynchobdellida appears to be a non-monophyletic group which is not consistent with previous molecular results

Plant-Type Trehalose Synthetic Pathway in Cryptosporidium and Some Other Apicomplexans

The trehalose synthetic pathway is present in bacteria, fungi, plants and invertebrate animals, but is absent in vertebrates. This disaccharide mainly functions as a stress protectant against desiccation, heat, cold and oxidation. Genes involved in trehalose synthesis have been observed in apicomplexan parasites, but little was known about these enzymes. Study on trehalose synthesis in apicomplexans would not only shed new light into the evolution of this pathway, but also provide data for exploring this pathway as novel drug target.We have observed the presence of the trehalose synthetic pathway in Cryptosporidium and other apicomplexans and alveolates. Two key enzymes (trehalose 6-phosphate synthase [T6PS; EC 2.4.1.15] and trehalose phosphatase [TPase; EC 3.1.3.12] are present as Class II bifunctional proteins (T6PS-TPase) in the majority of apicomplexans with the exception of Plasmodium species. The enzyme for synthesizing the precursor (UDP-glucose) is homologous to dual-substrate UDP-galactose/glucose pyrophosphorylases (UGGPases), rather than the "classic" UDP-glucose pyrophosphorylase (UGPase). Phylogenetic recontructions indicate that both T6PS-TPases and UGGPases in apicomplexans and other alveolates are evolutionarily affiliated with stramenopiles and plants. The expression level of T6PS-TPase in C. parvum is highly elevated in the late intracellular developmental stage prior to or during the production of oocysts, implying that trehalose may be important in oocysts as a protectant against environmental stresses. Finally, trehalose has been detected in C. parvum oocysts, thus confirming the trehalose synthetic activity in this parasite.A trehalose synthetic pathway is described in the majority of apicomplexan parasites including Cryptosporidium and the presence of trehalose was confirmed in the C. parvum oocyst. Key enzymes in the pathway (i.e., T6PS-TPase and UGGPase) are plant-type and absent in humans and animals, and may potentially serve as novel drug targets in the apicomplexans

THE CONCENTRATION OF TREHALOSE AND ACITVITY OF TREHALASE FROM GALLERIA MELLONELLA LARVAE INFECTED BY STEINERNEMA AFFFINIS, BOVIEN 1937 (NEMATODA: RHABDITIDA: STEINERNEMATIDAE)

The experimental studies were conducted on caterpillars of wax moth Galleria mellonella infected with Steinernema affinis larvae. The concentration of trehalose and the activity of trehal ase were measured during the invasion lasting 48h. The level of trehalose and activity of enzyme were slightly lower in infected insects in comparison to the control animals

Composition of fatty acids in the Varroa destructor mites and their hosts, Apis mellifera drone-prepupae

The fatty acid (FA) profile of lipids extracted from the Varroa destructor parasitic mite and its host, drone prepupae of Apis mellifera, was determined by gas chromatography (GC). The percentages of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) were generally similar in parasites and their hosts. Fatty acids were arranged in the following descending order based on their content: MUFAs (ca. 52–55%), SFAs (ca. 41%) and PUFAs (ca. 3%). The predominant fatty acids were oleic acid (46% in mites, 44% in prepupae) and palmitic acid (23% and 30%, respectively). Varroa parasites differed from their hosts in the quantity of individual FAs and in their FA profiles. Three PUFAs noted in the host were not observed in parasitic mites, whereas the presence of C21:0, C24:0 and C22:1 FAs was reported in mites, but not in drones

Inkubacja doroslych osobnikow Ascaris suum w mediach chemicznie zdefiniowanych

Adult Ascaris suum were incubated at 37°C in Ringer solution for Ascaris (ARSb) and in ARSb with 0.2 % addition of glucose, maltose, trehalose, saccharose, starch and glycogen. Control worms were incubated in ARSb without natrium acetate (ARS0). The survival rate, motility and elasticity of each individual, changes of the body weight and glycogen contents in muscles were determined. The incubation in ARS0 was finished on the 7th day. The longest (11 days) lived the worms kept in the basic medium ARSb and ARSb with maltose. Regarding their influence on the survival rate of parasites, the rest sugars could be set in order as follows: glycogen and glucose (10 days), trehalose, saccharose and starch (9 days). In the media containing saccharose and starch worms showed reduced motility and elasticity. On the 7th day of incubation the glycogen level in muscles of control worms was reduced to 0.75% of its beginning concentration, whereas in muscles of Ascaris from media with glucose and trehalose over 50% and with maltose 43% of polysaccharide's reserves were preserved. A slight increase (10-15%) in average body weight of worms incubated with glucose, maltose and glycogen was observed, only in the control and medium with saccharose changes of worms' mass were significant, amounting to 30% and 80%, respectively

The total protein content, protein fractions and proteases activities of drone prepupae of Apis mellifera due to varrosis

The proteins level and activities of acid and alkaline proteases in whole body extracts of drone prepupae of Apis mellifera naturaly infested with Varroa destructor were studied. The infested and a non-infested group did not differ significantly in their total protein content. However, some differences in protein profiles were found. A lack of three protein fractions of moderate and lower molecular weight in infested prepupae was noted. Moreover, some differences in the quantity of protein in most of the fractions were observed. The activity of acid proteases from infested prepupae was lower (p < 0.05) compared with the activity of these proteases from the non-infested one group. The infested drone had higher activity of alkaline proteases than non-infested but this difference was not statisticaly significant