Abstract：
:Culture forms of Leishmania (Leishmania) amazonensis (IFLA/BR/67/PH8) produce an extracellular enzyme that hydrolyzes sucrose molecules into their component monosaccharides. This is important because phlebotomine sand flies, the invertebrate hosts of Leishmania, ingest plant sap or aphid and coccid honeydew rich in sucrose between blood meals and Leishmania promastigotes cannot uptake sucrose. The sucrase was purified and characterized; its molecular weight, estimated by gel filtration chromatography and SDS-PAGE electrophoresis, was about 73 kDa. K(m) and V(max) measured with sucrose as substrate were respectively 4.4 mM and 6.9 mumole glucose.min-1 (mg sucrase)-1, with maximum pH activity at pH 5.5. A series of natural and p-nitrophenyl-derived substrates were assayed, characterizing the enzyme as a highly specific beta-D-fructofuranoside fructohydrolase. When 11 species of Leishmania and 7 genera of trypanosomatids were screened, only the species of the genus Trypanosoma did not produce an enzyme with saccharolytic activity. These data are in agreement with the fact that the latter vectors do not acquire sucrose or raffinose in their meals. Searching for glycolytic enzymes other than sucrase, we found an N-acetyl-beta-D-galactosaminolytic activity. This N-acetyl-galactosaminidase, here described for the first time, might have a role in peritrophic membrane disruption. The importance of sucrase and N-acetyl-beta-D-galactosaminidase in the Leishmania life cycle is discussed.
journal_name
Exp Parasitoljournal_title
Experimental parasitologyauthors
Gontijo NF,Melo MN,Riani EB,Almeida-Silva S,Mares-Guia MLdoi
10.1006/expr.1996.0055subject
Has Abstractpub_date
1996-06-01 00:00:00pages
117-24issue
1eissn
0014-4894issn
1090-2449pii
S0014-4894(96)90055-7journal_volume
83pub_type
杂志文章abstract：:A systematic study of the distribution of intracellular parasites in the organs and tissues of mice acutely infected (15 days) with the CL strain of Trypanosoma cruzi was performed. Almost all tissues and organs were parasitized with different intensities, including several epithelial cell types. In addition to striat...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1996.0086
更新日期：1996-10-01 00:00:00
abstract：:Pyruvate kinase (PK; EC 2.7.1.40) and phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.32) are essential regulatory enzymes of glucose oxidation in helminths, the PK/PEPCK branch point being the first divergent step between carbohydrate catabolism of the parasites and their hosts. Recently, PEPCK from the cestode pa...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2015.03.023
更新日期：2015-06-01 00:00:00
abstract：:The cDNA of a Schistosoma japonicum myophilin-like protein was cloned, sequenced, and expressed in Escherichia coli as a recombined protein (rSj myophilin-like protein), and the protein was purified by affinity chromatography. The deduced amino acid sequences of the Sj myophilin-like protein showed significant homolog...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2008.01.017
更新日期：2008-05-01 00:00:00
abstract：:The aim of this study was to evaluate the effects of selenium and copper on oxidative stress and its performance in lambs experimentally infected with Haemonchus contortus. Twenty-eight five-months old lambs were experimentally infected by the oral route with 5000 third-stage infective larvae and allocated into four g...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2014.06.005
更新日期：2014-09-01 00:00:00
abstract：:To better control gastrointestinal nematode infections in humans and animals, it is important to understand the strategies used by these parasites to modulate the host immune system. In this regard, molecules released by parasites have been attributed crucially important roles in host-parasite negotiations. We charact...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2017.05.003
更新日期：2017-07-01 00:00:00
abstract：:The glycosomes of trypanosomatids are essential organelles that are evolutionarily related to peroxisomes of other eukaryotes. The peroxisomal RING proteins-PEX2, PEX10 and PEX12-comprise a network of integral membrane proteins that function in the matrix protein import cycle. Here, we describe PEX10 and PEX12 in Tryp...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2006.11.004
更新日期：2007-05-01 00:00:00
abstract：:We compared in vitro and in vivo induction of IL-12 (p40) and IFN-gamma by mouse cells stimulated with Toxoplasma gondii, Trypanosoma cruzi, and different species of Leishmania. Spleen cells cultured in vitro with T. cruzi or T. gondii, but not with Leishmania, produced IL-12 (p40) and IFN-gamma. Accordingly, IL-12 (p...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.2000.4523
更新日期：2000-06-01 00:00:00
abstract：:The existence of cholinergic receptors in the immune system cells is well documented. This study aimed to evaluate the acetylcholinesterase activity (AChE) in lymphocytes from rats infected with Trypanosoma evansi in acute and chronic phase disease. Twenty animals were infected with 10(6) trypomastigotes forms each an...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2010.10.017
更新日期：2011-02-01 00:00:00
abstract：:Aedes aegypti mosquitoes salivate during intradermal probing of vertebrate prey before ingesting blood (Griffiths and Gordon 1952). Nonsalivating mosquitoes locate blood more slowly; this difference was ascribed to an anti-platelet activity found in the mosquito's saliva (Ribeiro et al. 1984). Mosquitoes infected with...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/s0014-4894(85)80029-1
更新日期：1985-08-01 00:00:00
abstract：:The prevalence of Cryptosporidium and microsporidia in feral horses, which have minimal contact with livestock and humans, is not currently known. We report the findings of a study on Cryptosporidium and microsporidia in 34 Mustangs and 50 Chincoteague ponies in the USA. Fecal samples were screened for presence of Cry...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2015.12.004
更新日期：2016-03-01 00:00:00
abstract：:Clonorchis sinensis is a fish-borne trematode endemic to East Asia, which infects over 35 million people globally. In the study described here, we developed a nested polymerase chain reaction (PCR) method for the specific and reliable detection of C. sinensis. The primers designed from the nucleotide sequence data der...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2006.09.010
更新日期：2007-03-01 00:00:00
abstract：:Allelic variation in the Plasmodium falciparum merozoite surface protein 1 (MSP1) gene is expressed as an association of allelic types in variable blocks. In this study, a PCR strategy that can detect 24 different MSP1 association types was used to investigate allelic variation in the MSP1 gene. We identified 236 dist...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1997.4147
更新日期：1997-05-01 00:00:00
abstract：:Homogenates of Giardia lamblia trophozoites exhibited the following hydrolase activities: acid phosphatase (EC 3.1.3.2), proteinase (EC 3.1.4) with urea-denatured hemoglobin and N-benzoyl-DL-arginine-2-naphthylamide as substrates, deoxyribonuclease (EC 3.1.4.5), and ribonuclease (EC 2.7.7.16). beta-N-Acetylglucosamini...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(88)90116-6
更新日期：1988-02-01 00:00:00
abstract：:Polymerase chain reaction amplification of several polymorphic genes has been used to study the population biology of Plasmodium falciparum. S antigen is particularly suitable for such studies, but difficulties in the amplification of this gene have precluded its use. Here we describe a simple method for the amplifica...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1993.1108
更新日期：1993-12-01 00:00:00
abstract：:Early diagnosis and determining the infective stage are critical for effective therapy of toxoplasmosis. Owing to the progress in biotechnology, commonly used native, non-standardized diagnostic antigens should be replaced by genetically engineered antigens. The recombinant proteins are also promising components of su...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2015.01.006
更新日期：2015-03-01 00:00:00
abstract：:A ceramide-anchored glycophosphosphingolipid antigen was isolated from the lipid extract of Leishmania donovani promastigotes. The affinity-purified glycolipid antigen contained galactose, mannose, myo-inositol, phosphate, ceramide, and hexosamine but no sialic acid. The phosphate group was present internally at the c...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(92)90148-4
更新日期：1992-05-01 00:00:00
abstract：:A method is described for the isolation of peroxisomes from mitochondria-enriched fractions obtained from both species of nematodes. The distributions of these organelles are characterized after density gradient centrifugation in sucrose or Percoll by urate oxidase and catalase activities. The possession of peroxisome...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(90)90026-9
更新日期：1990-08-01 00:00:00
abstract：INTRODUCTION:It has been reported that behavioral changes relate to infection in different parasitoses. However, the relation between the extent of the behavioral changes and the magnitude of the infection has been scarcely studied. The aim of this study was to evaluate the relationship between different doses of infec...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2016.04.013
更新日期：2016-07-01 00:00:00
abstract：:Three different cell lines (murine macrophages, HeLa and osteosarcoma cells) were assayed in order to check for the manifestation of the cytopathic effects of three strains of Acanthamoeba recently isolated in our laboratory from contact lens cases: CLC-16, CLC-41.r and CLC-51-l. Adhesion and cytotoxicity assays were ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2009.10.011
更新日期：2010-09-01 00:00:00
abstract：:Trypanosomatid protozoa lack consensus promoters for RNA polymerase (RNAP) II. However, the artificial insertion of the T7 promoter (P(T7)) and the tetracycline repressor into Trypanosoma brucei cell lines expressing T7RNAP allows P(T7)-driven gene expression to be tetracycline-inducible. These cell lines provide a mo...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2007.01.001
更新日期：2007-07-01 00:00:00
abstract：:Live adult and juvenile entomopathogenic Steinernema carpocapsae DD136 (P. Nematoda) were not subjected to adhesion by haemocytes of lepidopteran insect larvae of Galleria mellonella or Malacosoma disstriain vitro or in vivo. In vitro freeze-killed nematodes exhibited haemocyte attachment, the intensity increasing wit...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2008.07.001
更新日期：2008-10-01 00:00:00
abstract：:Root lesion nematodes (RLNs, Pratylenchus species) are a group of economically important migratory endoparasitic plant pathogens that attack host roots of major crops such as wheat and sugarcane, and can reduce crop yields by 7-15%. Pratylenchus thornei and Pratylenchus zeae were treated with double stranded RNA (dsRN...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2012.11.011
更新日期：2013-02-01 00:00:00
abstract：:A cell-free culture system for Cryptosporidium parvum was analysed using scanning electron microscopy (SEM) to characterise life cycle stages and compare gene expression in cell-free culture and cell culture using HCT-8 cells. Cryptosporidium parvum samples were harvested at 2 h, 8 h, 14 h, 26 h, 50 h, 74 h, 98 h, 122...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2015.03.002
更新日期：2015-06-01 00:00:00
abstract：:Partial nucleotide sequences of large subunit ribosomal RNA (LSU rRNA) coding genes of Theileria parva and T. taurotragi were determined. Alignment of the T. parva and T. taurotragi sequences revealed species-specific regions within the LSU rRNA genes. A major species-variable region, located between the first and sec...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1995.1012
更新日期：1995-02-01 00:00:00
abstract：:Opisthorchis viverrini is the only liver fluke that has been proved to be associated with cholangiocarcinoma (CCA). However, the mechanisms by which O. viverrini participates in the carcinogenesis of CCA are still unclear. To understand the biology and host-parasite interaction related to O. viverrini infection, gene ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2008.08.004
更新日期：2008-12-01 00:00:00
abstract：:Resistance and sensitivity to normal human serum (NHS) of Trypanosoma congolense, a parasite believed to cause disease in animals only, were investigated in vivo as well as in vitro. Our results indicate that like Trypanosoma brucei, T. congolense can be grouped into three different phenotypes according to its resista...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/s0014-4894(03)00032-8
更新日期：2002-10-01 00:00:00
abstract：:According to the World Health Organization, lymphatic filariasis (LF), a mosquito-borne neglected tropical disease (NTD), should be eliminated as a public health concern by the end of 2020. To this end, the goals of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) include interrupting transmission throug...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2020.107918
更新日期：2020-08-01 00:00:00
abstract：:Reliable analytical techniques to test growth-promoting and antimalarial efficacy on plasmodia are very important. Flow cytometry (FCM) offers the possibility to study developmental stages of intraerythrocytic growth of malaria parasites using nucleic acid staining. To analyze the growth of Plasmodium falciparum SYBR ...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/j.exppara.2008.10.008
更新日期：2009-02-01 00:00:00
abstract：:Giardia lamblia consist of heterogeneous isolates that can be divided into at least three groups. Differential screening of a cDNA library with isolate-specific antisera identified a gene which is expressed and found only in Group 3 isolates. This gene, GLORF-C4, is 597 bp in length and predicts a deduced protein of 1...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1016/0014-4894(92)90250-e
更新日期：1992-12-01 00:00:00
abstract：:As an approach to better understand the molecular mechanisms underlying the differential cellular response to larval Schistosoma mansoni observed in Biomphalaria glabrata, we have analyzed hemocyte membrane-associated polypeptides from inbred susceptible and resistant strains of B. glabrata. A combination of technique...
journal_title：Experimental parasitology
pub_type： 杂志文章
doi：10.1006/expr.1994.1053
更新日期：1994-08-01 00:00:00
