Abstract:
:Trophozoites of Entamoeba invadens were able to ingest glucopolysaccharides and metabolize them. An activity capable of degrading these substrates was purified to apparent homogeneity. The enzyme was identified as beta-amylase (alpha-1,4-D-glucan maltohydrolase EC 3.2.1.2): It was active against glycogen, amylose and amylopectin in a ratio of 100:198:133 and was also able to attack linear alpha-1,4-glucooligosaccharides with more than three glucose moieties. All degradation experiments yielded maltose as reaction product, and no free glucose could be detected. While amylose was completely degraded, amylolysis of glycogen and amylopectin yielded limit dextrins besides maltose. The enzyme was completely inactive against cyclohexaamylose, cycloheptaamylose and pullulan, indicating its lack of endo-glucosidase specificity. Hydrolysis of 4-nitrophenyl-maltoheptaoside resulted in the successive removal of maltose units from the non-reducing end yielding 4-nitrophenyl-maltopentaoside, -trioside and -glucoside. No 4-nitrophenyl-glycosides with even numbered glucose moieties were formed from this substrate. The enzyme exhibited a relative molecular mass of M(r) = 45,000 +/- 5% by gel filtration and sodium dodecyl sulfate (SDS) gel electrophoresis and the N-terminal sequence 1 VEVNVMLPL 9. Optimal hydrolysis was observed at pH 5.5 and a temperature of 42 degrees C. On the basis of inhibition by mercury ions and p-chloro-mercurybenzoate and abrogation of this effect by thiol reagents beta-amylase was identified as sulfhydryl-enzyme.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Serafimova F,Franz A,Werries Edoi
10.1016/s0166-6851(96)02765-xsubject
Has Abstractpub_date
1996-12-20 00:00:00pages
175-81issue
2eissn
0166-6851issn
1872-9428pii
S0166-6851(96)02765-Xjournal_volume
83pub_type
杂志文章abstract::Clones which were selected from a Toxoplasma gondii expression library with the immune serum from a T. gondii-infected rabbit, were further screened using milk and intestinal secretions from mice which had been orally infected with T. gondii cysts. The gene products of several clones reacted strongly with milk IgA and...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(92)90172-g
更新日期:1992-12-01 00:00:00
abstract::The complete sequence of the gene coding for the S antigen from the Wellcome (West African) strain of Plasmodium falciparum has been obtained. It contains a central repetitive region consisting of 65 copies of a partially degenerate 24 bp sequence, coding for a conserved 8 amino acid repeat (Gly Pro Asn Ser Asp Gly As...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(88)90174-0
更新日期:1988-02-01 00:00:00
abstract::Cloned DNA fragments of the ribosomal RNA gene of Schistosoma mansoni hybridise strongly to Echinococcus DNA following restriction endonuclease and Southern transfer analysis. Individuals within a strain of E. granulosus exhibit identical patterns of hybridisation. However, the hybridisation patterns show significant ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(85)90016-7
更新日期:1985-11-01 00:00:00
abstract::The primary S(1) subsite specificity of a recombinant cysteine proteinase, CPB2.8 Delta CTE, of Leishmania mexicana was investigated in a systematic way using a series of peptides derived from Abz-KLRFSKQ-EDDnp in which Arg was substituted by all natural amino acids (where Abz is ortho-amino-benzoyl and EDDnp is N-[2,...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(01)00290-0
更新日期:2001-08-01 00:00:00
abstract::Cytoadherence of infected erythrocytes is a hallmark of Plasmodium falciparum infection and a key determinant in the particular virulence of this species. Infected erythrocytes bind a variety of host receptors but certain adhesion traits are associated with more severe disease. A large, diverse protein family named P....
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(03)00099-9
更新日期:2003-06-01 00:00:00
abstract::Eukaryotic cells can degrade their own components, cytosolic proteins and organelles, using dedicated hydrolases contained within the acidic interior of their lysosomes. This degradative process, called autophagy, is used under starvation conditions to recycle redundant or less important macromolecules, facilitates me...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
doi:10.1016/j.molbiopara.2011.02.003
更新日期:2011-06-01 00:00:00
abstract::We have compared a total of 44 recognition sites for 12 restriction endonucleases on the 20 kilobase pair maxi-circle of kinetoplast DNA from nine Trypanosoma brucei stocks, four which are known to be infective to man (tow 'gambiense' and two 'rhodesiense' variants). In addition to five polymorphic sites, these DNAs d...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(81)90011-6
更新日期:1981-06-01 00:00:00
abstract::A mild surface-labeling procedure was applied to various developmental stages of Schistosoma mansoni. An 18 kDa protein was preferentially labeled in freshly transformed schistosomula. The labeled protein was equally present on skin-penetrated and mechanically prepared schistosomula and it disappeared upon digestion o...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(86)90050-2
更新日期:1986-01-01 00:00:00
abstract::Natural antisense transcripts (NATs) are non-protein coding RNAs that could play an important role in regulating the expression of their counterpart protein encoding sense transcript. Although NATs are widespread in most eukaryotic genomes, very little is known about their functions. This study focuses on gaining a be...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2020.111334
更新日期:2020-11-01 00:00:00
abstract::Erythrocytes from Plasmodium berghei-infected mice on incubation either in plasma or artificial isotonic media showed an increase in uptake of 45Ca2+ compared with erythrocytes from uninfected mice. Infected cells (55% parasitaemia) incubated in plasma from normal or infected mice gave uptake rates of 9.8 and 8.1 nmol...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(83)90023-3
更新日期:1983-03-01 00:00:00
abstract::RAB proteins are small GTPases with vital roles in eukaryotic intracellular transport; orthologous RABs appear to fulfil similar functions in diverse organisms. Trypanosoma brucei spp., the causative organisms of Old World trypanosomiasis of humans and domestic animals, have extremely effective endocytic and exocytic ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2005.01.017
更新日期:2005-05-01 00:00:00
abstract::The DNA contents of three different Trypanosoma cruzi strains were compared by direct microfluorometry. The maximal difference found was 40% of the lowest value. Two of the cloned strains, reported in an earlier study to differ by 48% in their total DNA content, showed a difference of 33%. The kinetoplast of the Y str...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(89)90202-8
更新日期:1989-08-01 00:00:00
abstract::The FAR proteins of nematodes are small ( approximately 20 kDa), helix-rich, fatty acid and retinol-binding (FAR) proteins that appear to be confined to nematodes. We have carried out a comparative sequence and biochemical analysis of selected FAR proteins often species of filarial parasites (from the genera Onchocerc...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(02)00097-x
更新日期:2002-07-01 00:00:00
abstract::A group of Leishmania mexicana cysteine proteases that differ from those previously found in this protozoon are described. The enzymes characteristically have a preference for peptidyl substrates with a phenylalanyl-valyl-arginyl moiety, do not hydrolyse gelatin in substrate-sodium dodecyl sulphate polyacrylamide gels...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(93)90116-f
更新日期:1993-12-01 00:00:00
abstract::In Leishmania mexicana two genes were detected coding for different isoforms of the glycolytic enzyme phosphoglycerate kinase. This situation contrasts with that observed in other Trypanosomatidae (Trypanosoma brucei, Trypanosoma congolense, Crithidia fasciculata) analyzed previously, which all contain three different...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(97)00152-7
更新日期:1997-12-01 00:00:00
abstract::A convenient method was employed for the efficient extraction of total RNA from Plasmodium falciparum. By depleting the total RNA of tRNA, it was shown that P. falciparum or P. lophurae tRNAs markedly stimulate the translation of P. falciparum mRNA in the rabbit reticulocyte cell-free system. Analysis of the cell-free...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(82)90023-8
更新日期:1982-12-01 00:00:00
abstract::The apicoplast is a highly specialized organelle that mediates required functions in the growth and replication of apicomplexan parasites. Despite structural conservation of the apicoplast among different parasite genera and species, there are also critical differences in the metabolic requirements of different parasi...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2011.10.009
更新日期:2012-02-01 00:00:00
abstract::Sequestration of Plasmodium falciparum infected erythrocytes in the cerebral circulation is strongly implicated in the pathogenesis of cerebral malaria. From previous studies it was postulated that genes essential for cytoadherence were located on the right arm of chromosome 9 as P. falciparum isolates with a deletion...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(94)90092-2
更新日期:1994-09-01 00:00:00
abstract::The principal constituents of the free amino acid pool in Leishmania tropica promastigotes include alanine, glycine, serine, threonine, alpha-aminobutyric acid and ethanolamine. Changes in levels of the pool constituents during starvation, nutrient supplementation and treatment with a metabolic inhibitor (sodium fluor...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(83)90056-7
更新日期:1983-09-01 00:00:00
abstract::Genetic transformation of malaria parasites has been limited by the number of selectable markers available. For the rodent malaria parasite, Plasmodium berghei, only a single selection marker has been at hand, utilising the dihydrofolate reductase-thymidylate synthase gene from either P. berghei or Toxoplasma gondii t...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(99)00189-9
更新日期:2000-03-05 00:00:00
abstract::Amoebiasis is spread by the ingestion of dormant Entamoeba histolytica cysts. Intervention of encystation could break the transmission cycle, thereby reducing disease burden. The model system used to study trophozoite to cyst differentiation is Entamoeba invadens. Here we describe an electroporation-based method for s...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2012.02.012
更新日期:2012-07-01 00:00:00
abstract::Opisthorchis viverrini is the causative agent of human opisthorchiasis in Thailand and long lasting infection with the parasite has been correlated with the development of cholangiocarcinoma. In this work we have molecularly characterized the first member of a protein family carrying two DM9 repeats in this parasite (...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2016.04.002
更新日期:2016-05-01 00:00:00
abstract::Schistosomiasis is an intravascular parasitic infection estimated to affect over 206 million people, the majority of whom live in Africa where the trematode worms Schistosoma mansoni and Schistosoma haematobium are the major causative agents. While a number of drugs have been used to treat schistosomiasis, praziquante...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2018.12.005
更新日期:2019-03-01 00:00:00
abstract::Pathogens of the Leishmania and Trypanosoma genera compartmentalize glycolytic and other nutritional pathways in glycosomes, unique subcellular organelles related to the peroxisomes of mammals and yeasts. Most glycosomal proteins are targeted to the glycosomes by a COOH-terminal tripeptide signal similar to the peroxi...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(02)00164-0
更新日期:2002-09-01 00:00:00
abstract::Genetic variation among malaria parasites has important consequences with regard to drug resistance, pathogenicity, immunity, transmission, and speciation. In this regard, malaria parasites have been shown to display a high degree of inter- and intra-species genetic divergence. The nuclear genomes of Plasmodium falcip...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/s0166-6851(98)00093-0
更新日期:1998-09-01 00:00:00
abstract::Eimeria are the causative agents of coccidosis, a disease which is of world wide economic importance in the poultry industry. Immunity resulting from infection is species-specific and both antibody and cell-mediated responses have been implicated. As an initial step in the development of a genetically-engineered vacci...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(87)90071-5
更新日期:1987-01-02 00:00:00
abstract::Beta 1,3-glucan recognition proteins (GRP) have specific affinity for beta 1,3-glucan, a component on the surface of fungi and bacteria. By interacting with beta 1,3-glucan, GRP initiates activation of prophenoloxidase, a key enzyme in the signaling pathway leading to melanotic encapsulation in invertebrates. In this ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2004.09.009
更新日期:2005-01-01 00:00:00
abstract::The major surface antigen (30 kDa) of Brugia pahangi has been characterised by a number of biochemical and immunochemical means. The 30 kDa polypeptide is a glycoprotein which can be extracted from the worm surface by homogenization in the absence of detergents. The 30 kDa polypeptide can be metabolically labelled wit...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/0166-6851(88)90027-8
更新日期:1988-01-01 00:00:00
abstract::Helminths are masterful immunoregulators. A characteristic feature of helminth infection is a Th2-dominated immune response, but stimulation of immunoregulatory cell populations, such as regulatory T cells and alternatively activated macrophages, is equally common. Typically, Th1/17 immunity is blocked and productive ...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章,评审
doi:10.1016/j.molbiopara.2009.04.008
更新日期:2009-09-01 00:00:00
abstract::Plasmodium vivax infection is the second most common cause of malaria throughout the world. Like other Plasmodium species, P. vivax has a large protein complex, MSP-1, located on the merozoite surface. The C-terminal MSP-1 sub-unit, MSP-1(42), is cleaved during red blood cell invasion, causing the majority of the comp...
journal_title:Molecular and biochemical parasitology
pub_type: 杂志文章
doi:10.1016/j.molbiopara.2007.01.015
更新日期:2007-05-01 00:00:00