Abstract：
:The enzyme pterin-4a-carbinolamine dehydratase (PCD) is important for the recycling of pterins within eukaryotic cells. A recombinant expression system for PCD from the apicomplexan parasite Toxoplasma gondii has been prepared, the protein purified and crystallised. Single crystal X-ray diffraction methods have produced a high-resolution structure (1.6A) of the apo-enzyme and a low-resolution structure (3.1A) of a complex with a substrate-like ligand dihydrobiopterin (BH(2)). Analysis of the hydrogen bonding interactions that contribute to binding BH(2) suggest that the ligand is present in an enol tautomeric state, which makes it more similar to the physiological substrate. The enzyme can process (R)- and (S)-forms of pterin-4a-carbinolamine and the ligand complex suggests that His61 and His79 are placed to act independently as general bases for catalysis of the individual enantiomers. Comparisons with orthologues from other protozoan parasites (Plasmodium falciparum and Leishmania major) and with rat PCD, for which the structure is known, indicate a high degree of sequence and structure conservation of this enzyme. The molecular determinants of ligand recognition and PCD reactivity are therefore highly conserved across species.
journal_name
Mol Biochem Parasitoljournal_title
Molecular and biochemical parasitologyauthors
Cameron S,Fyffe SA,Goldie S,Hunter WNdoi
10.1016/j.molbiopara.2007.12.002subject
Has Abstractpub_date
2008-04-01 00:00:00pages
131-8issue
2eissn
0166-6851issn
1872-9428pii
S0166-6851(07)00337-4journal_volume
158pub_type
杂志文章abstract：:The gender of cercarial larvae can only be determined using molecular methods. End point PCR methods that amplify repetitive markers on the W chromosome of the female (ZW) parasites have been developed, but sometimes results are ambiguous or incorrect. To more effectively distinguish sexes, and to determine why end po...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2016.03.010
更新日期：2016-01-01 00:00:00
abstract：:Plasmodium falciparum extensively modifies the infected red blood cell (RBC), resulting in changes in deformability, shape and surface properties. These alterations suggest that the RBC cytoskeleton is a major target for modification during infection. However, the molecular mechanisms leading to these changes are larg...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2017.06.002
更新日期：2017-09-01 00:00:00
abstract：:Schistosomiasis remains a severe problem of public health in developing countries. Several reports show that praziquantel, the drug of choice for treating schistosomiasis, can select Schistosoma mansoni strains resistant to the drug. Thus, developing new drugs against this parasitosis is a highly desirable goal. Curcu...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2012.11.006
更新日期：2013-02-01 00:00:00
abstract：:Plasmodium falciparum malaria parasites invade human red blood cells and immediately begin making significant alterations to the structure of the erythrocyte. These alterations facilitate the movement of nutrients into, and waste products and parasite-derived proteins out of the cell to meet the needs of the growing p...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章,评审
doi：10.1016/0166-6851(95)02575-8
更新日期：1996-02-01 00:00:00
abstract：:This study further explores the effects of hypoxia and acute osmotic stress on intermediary metabolism of Leishmania major and Leishmania donovani. Late log phase promastigotes were washed and incubated with glucose as the sole exogenous carbon source, and rates of glucose consumption and product formation were measur...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(92)90217-8
更新日期：1992-02-01 00:00:00
abstract：:Trichomonas vaginalis is a parasitic protozoan of both medical and biological relevance. Transcriptional studies in this organism have focused mainly on type II pol promoters, whereas the elements necessary for transcription by polI or polIII have not been investigated. Here, with the aid of a transient transcription ...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2012.05.004
更新日期：2012-09-01 00:00:00
abstract：:Genomic structure has been determined for a gene encoding a host-protective antigen of the parasitic platyhelminth Taenia ovis. An incomplete cDNA, known as 45W, encodes the protective antigen. Southern hybridisation experiments using 45W cDNA as a probe, revealed that the 45W gene was a member of a multigene family. ...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(94)00104-u
更新日期：1995-07-01 00:00:00
abstract：:Several proteins synthesized by mature asexual stages of Plasmodium falciparum interact with the erythrocyte membrane skeleton. One of these is the mature-parasite-infected erythrocyte surface antigen (MESA; also called PfEMP2), a phosphoprotein of 250-300 kDa, which is found on the internal face of the erythrocyte me...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(90)90029-l
更新日期：1990-01-15 00:00:00
abstract：:Plasmodium falciparum invades human erythrocytes by redundant pathways. Unlike Plasmodium vivax that has one Duffy Binding-Like (DBL) receptor, P. falciparum has four members of the DBL receptor family. Furthermore, one of these DBL genes, BAEBL, has polymorphisms at four amino acids in region II; each polymorphism bi...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2009.06.006
更新日期：2009-11-01 00:00:00
abstract：:Tubulin genes in Trypanosoma rangeli, the only trypanosome besides T. cruzi to infect humans in America, are organized in homogeneous, alternate alpha and beta gene tandem repeats of 3.8 kb. The basic repeat was cloned, mapped and partially sequenced. In contrast to most other eukaryotes, where tubulin genes are scatt...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(89)90054-6
更新日期：1989-05-15 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：:Two different classes of small nematode specific lipid-binding proteins, the nematode polyprotein allergens/antigens (NPAs) and the fatty acid- and retinol-binding (FAR) proteins, are secreted by helminth parasites. Until now, there was no evidence of the expression or secretion of these two families of proteins in Ha...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2009.07.001
更新日期：2009-11-01 00:00:00
abstract：:The pfmdr 1 gene encodes a Plasmodium falciparum homologue of the human P-glycoprotein expressed on the surface of the parasite food vacuole. Variation in copy number and specific codon mutations of pfmdr 1 have been implicated in the development of parasite resistance to antimalarial drugs. We describe here the techn...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/s0166-6851(96)02822-8
更新日期：1997-04-01 00:00:00
abstract：:Human hookworms (Ancylostoma duodenale, Necator americanus) are a major cause of malnutrition and anemia, particularly in children, and high worm burdens can lead to stunted growth and mental retardation. Mass drug administration (MDA) with benzimidazole (BZ) anthelmintics has the potential to greatly reduce morbidity...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2007.07.019
更新日期：2007-12-01 00:00:00
abstract：:With the rapid spread of drug-resistant strains of Plasmodium falciparum, the development of new antimalarials is an urgent need. As malaria parasites live in a highly pro-oxidant environment, their anti-oxidant defences have frequently been suggested as candidate drug targets. A key point in such defences is the prod...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2010.04.002
更新日期：2010-08-01 00:00:00
abstract：:Malarial merozoites use an array of ligands, including members of the Reticulocyte Binding Like (RBL) super-family of invasion proteins, to identify and invade erythrocytes. RBL family members are large Type I membrane anchored proteins expressed at the invasive end of merozoites that share homology with the Reticuloc...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2003.10.017
更新日期：2004-02-01 00:00:00
abstract：:Repeated DNA sequences have been instrumental in the development of DNA probes for many different parasites. Isolation of such DNA probes has generally been accomplished by differential screening of genomic libraries with total genomic DNA preparations. In the current work, a rational design strategy is presented for ...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(93)90047-2
更新日期：1993-04-01 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：: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：:The minichromosomes M210 and M230 of Leishmania major are linear amplicons which have an inverted repeat structure. We report here the molecular cloning of the megabasic chromosome region where M210 and M230 recombination points are located. The analysis of this chromosomal region revealed a 374 bp fragment directly r...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(96)02724-7
更新日期：1996-11-25 00:00:00
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journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2004.11.003
更新日期：2005-02-01 00:00:00
abstract：:Proteases play central roles in cell invasion by Toxoplasma gondii and other apicomplexan parasites. Herein we report the cloning and characterization of a novel secretory putative metalloproteinase, Toxolysin 4 (TLN4). T. gondii tachyzoites store TLN4 in the micronemes and secrete it in response to elevated calcium, ...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2011.01.009
更新日期：2011-05-01 00:00:00
abstract：:Hamsters infected with Opisthorchis viverrini, a liver fluke of man, showed an increased deposition of collagen in their livers. However, increased collagen breakdown as well as its synthesis were observed in the infected livers. Thus, stimulated synthesis might be the main factor responsible for the net increase in c...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(83)90035-x
更新日期：1983-05-01 00:00:00
abstract：:Kinetoplast DNA (kDNA) networks of the insect trypanosomatid Crithidia fasciculata strain CF-C1 contain a nearly homogeneous population of kDNA minicircles as judged by restriction enzyme cleavage analysis. We have determined the entire nucleotide sequence of the major class of minicircles by analyzing M13 phage clone...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(87)90032-6
更新日期：1987-04-01 00:00:00
abstract：:A genomic clone, pTt21, containing DNA apparently transcribed specifically in Trypanosoma cruzi trypomastigotes, was obtained by differentially screening a genomic library with trypomastigote and epimastigote cDNA. This 3444-bp clone contained open reading frames at each end, separated by a 1.8-kb non-coding region. T...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(92)90159-h
更新日期：1992-11-01 00:00:00
abstract：:Schistosoma mansoni eggs, consisting of an ovum surrounded by nutritive vitelline cells packaged in a tanned protein shell, are produced by paired worms residing in the mesenteric veins of the human host. The vitelline cells are degraded as the larval miracidium matures, the fully developed egg either crossing the gut...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2010.10.005
更新日期：2011-02-01 00:00:00
abstract：:Translation initiation factor eIF4F is essential for cap-dependent translation initiation in eukaryotes. eIF4F is a trimeric complex consisting of a scaffold protein eIF4G, cap-binding protein eIF4E and DEAD-box RNA helicase eIF4A. eIF4F binds to the 5' cap structure of the mRNA through eIF4E and facilitates the bindi...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2020.111258
更新日期：2020-03-01 00:00:00
abstract：:Adult males and females of the dog heartworm, Dirofilaria immitis, were extracted separately and, following separation of the free and conjugated ecdysteroid fractions, the conjugates were hydrolysed enzymically. Both the ecdysteroids released by hydrolysis of the conjugates and the free hormones were further purified...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(83)90098-1
更新日期：1983-11-01 00:00:00
abstract：:We have initiated a project to characterize telomere-associated proteins of Cryptosporidium parvum. Searching public databases with C. parvum expressed sequence tag (EST) sequences revealed one EST sequence that is highly similar to Gbp1p of Chlamydomonas reinhardtii (Cr Gbp1p), a protein that binds single-stranded te...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/j.molbiopara.2009.01.013
更新日期：2009-06-01 00:00:00
abstract：:We have investigated the protein and glycoprotein content of Plasmodium falciparum merozoites by metabolically labeling cultures of schizont-stage parasites with [35S]methionine or with [3H]glucosamine followed by incubation in nonradioactive medium to allow the schizonts to mature into merozoites, infect new erythroc...
journal_title：Molecular and biochemical parasitology
pub_type： 杂志文章
doi：10.1016/0166-6851(84)90030-6
更新日期：1984-03-01 00:00:00
