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1.
Tanabe K Sakihama N Hattori T Ranford-Cartwright L Goldman I Escalante AA Lal AA 《Journal of molecular evolution》2004,59(5):687-694
The time to the most recent common ancestor of the extant populations of Plasmodium falciparum is controversial. The controversy primarily stems from the limited availability of sequences from Plasmodium reichenowi, a chimpanzee malaria parasite closely related to P. falciparum. Since the rate of nucleotide substitution differs in different loci and DNA regions, the estimation of genetic distance between P. falciparum and P. reichenowi should be performed using orthologous sequences that are evolving neutrally. Here, we obtained full-length sequences of two housekeeping genes, sarcoplasmic and endoplasmic reticulum Ca2+-ATPase (serca) and lactate dehydrogenase (ldh), from 11 isolates of P. falciparum and 1 isolate of P. reichenowi and estimate the interspecific genetic distance (divergence) between the two species and intraspecific genetic distance (polymorphism) within P. falciparum. Interspecific distance and intraspecific distance at synonymous sites of interspecies-conserved regions of serca and ldh were 0.0672±0.0088 and 0.0011±0.0007, respectively, using the Nei and Gojobori method. Based on the ratio of interspecific distance to intraspecific distance, the time to the most recent common ancestor of P. falciparum was estimated to be (8.30±5.40) × 104 and (11.62±7.56) × 104 years ago, assuming the divergence time of the two parasite species to be 5 and 7 million years ago, respectively.This article contains an online supplementary table.Reviewing Editor: Dr. Martin Kreitman 相似文献
2.
Mattis Kupferschmid Moyira Osny Aquino-Gil Hosam Shams-Eldin Jörg Schmidt Nao Yamakawa Frédéric Krzewinski Ralph T. Schwarz Tony Lefebvre 《Malaria journal》2017,16(1):485
Background
Post-translational modifications (PTMs) constitute a huge group of chemical modifications increasing the complexity of the proteomes of living beings. PTMs have been discussed as potential anti-malarial drug targets due to their involvement in many cell processes. O-GlcNAcylation is a widespread PTM found in different organisms including Plasmodium falciparum. The aim of this study was to identify O-GlcNAcylated proteins of P. falciparum, to learn more about the modification process and to understand its eventual functions in the Apicomplexans.Methods
The P. falciparum strain 3D7 was amplified in erythrocytes and purified. The proteome was checked for O-GlcNAcylation using different methods. The level of UDP-GlcNAc, the donor of the sugar moiety for O-GlcNAcylation processes, was measured using high-pH anion exchange chromatography. O-GlcNAcylated proteins were enriched and purified utilizing either click chemistry labelling or adsorption on succinyl-wheat germ agglutinin beads. Proteins were then identified by mass-spectrometry (nano-LC MS/MS).Results
While low when compared to MRC5 control cells, P. falciparum disposes of its own pool of UDP-GlcNAc. By using proteomics methods, 13 O-GlcNAcylated proteins were unambiguously identified (11 by click-chemistry and 6 by sWGA-beads enrichment; 4 being identified by the 2 approaches) in late trophozoites. These proteins are all part of pathways, functions and structures important for the parasite survival. By probing clicked-proteins with specific antibodies, Hsp70 and α-tubulin were identified as P. falciparum O-GlcNAc-bearing proteins.Conclusions
This study is the first report on the identity of P. falciparum O-GlcNAcylated proteins. While the parasite O-GlcNAcome seems close to those of other species, the structural differences exhibited by the proteomes provides a glimpse of innovative therapeutic paths to fight malaria. Blocking biosynthesis of UDP-GlcNAc in the parasites is another promising option to reduce Plasmodium life cycle.3.
Judy Orikiiriza Izabella Surowiec Elisabeth Lindquist Mari Bonde Jimmy Magambo Charles Muhinda Sven Bergström Johan Trygg Johan Normark 《Metabolomics : Official journal of the Metabolomic Society》2017,13(4):41
Introduction
Several studies have observed serum lipid changes during malaria infection in humans. All of them were focused at analysis of lipoproteins, not specific lipid molecules. The aim of our study was to identify novel patterns of lipid species in malaria infected patients using lipidomics profiling, to enhance diagnosis of malaria and to evaluate biochemical pathways activated during parasite infection.Methods
Using a multivariate characterization approach, 60 samples were representatively selected, 20 from each category (mild, severe and controls) of the 690 study participants between age of 0.5–6 years. Lipids from patient’s plasma were extracted with chloroform/methanol mixture and subjected to lipid profiling with application of the LCMS-QTOF method.Results
We observed a structured plasma lipid response among the malaria-infected patients as compared to healthy controls, demonstrated by higher levels of a majority of plasma lipids with the exception of even-chain length lysophosphatidylcholines and triglycerides with lower mass and higher saturation of the fatty acid chains. An inverse lipid profile relationship was observed when plasma lipids were correlated to parasitaemia.Conclusions
This study demonstrates how mapping the full physiological lipid response in plasma from malaria-infected individuals can be used to understand biochemical processes during infection. It also gives insights to how the levels of these molecules relate to acute immune responses.4.
Thymidylate synthase (TS) of Plasmodium dihydrofolate reductase-thymidylate synthase (DHFR-TS) functions as a homodimeric enzyme with two active sites located near
the subunit interface. The dimerization is essential for catalysis, since the active site of each subunit contains amino acid
residues contributed from the other TS domain. In P. falciparum DHFR-TS, it has been shown that the active sites require Cys-490 from one domain and Arg-470 donated from the other domain.
Mutants of these two series can complement one another giving rise to active enzyme. Here, the potential to form cross-species
heterodimers between P. falciparum and P. vivax TS has been explored. Formation of cross-species heterodimer was tested by co-transformation of TS-inactive Cys-490 mutants
of P. falciparum or P. vivax with corresponding TS-inactive Arg-486 mutants of P. vivax or P. falciparum into thymidine-requiring Escherichia coli. Active heterodimers were detected by subunit complementation and 6-[3H]-FdUMP binding assays. All combinations of the mutants tested, except for (Pf)R470A+(Pv)C506Y, were able to form catalytically
active cross-species heterodimers. The single active site formed by (Pf)R470D+(Pv)C506Y and (Pv)R486D+(Pf)C490A pairs of cross-species
heterodimers has k
cat and K
m values similar to those of intra-species heterodimers of P. falciparum and P. vivax. This is the first report to demonstrate that the TS subunit interface between Plasmodium species is sufficiently conserved to allow formation of fully active cross-species heterodimer. 相似文献
5.
Swati Garg Shalini Agarwal Surbhi Dabral Naveen Kumar Seema Sehrawat Shailja Singh 《Systems and synthetic biology》2015,9(1):23-26
Malaria, a leading parasitic killer, is caused by Plasmodium spp. The pathology of the disease starts when Plasmodium merozoites infect erythrocytes to form rings, that matures through a large trophozoite form and develop into schizonts containing multiple merozoites. The number of intra-erythrocytic merozoites is a key-determining factor for multiplication rate of the parasite. Counting of intraerythrocytic merozoites by classical 2-D microscopy method is error prone due to insufficient representation of merozoite in one optical plane of a schizont. Here, we report an alternative 3-D microscopy based automated method for counting of intraerythrocytic merozoites in entire volume of schizont. This method offers a considerable amount of advantages in terms of both, ease and accuracy. 相似文献
6.
Background
The adhesion of Plasmodium falciparum parasitized red blood cell (PRBC) to human endothelial cells (EC) induces inflammatory processes, coagulation cascades, oxidative stress and apoptosis. These pathological processes are suspected to be responsible for the blood-brain-barrier and other organs' endothelial dysfunctions observed in fatal cases of malaria. Atorvastatin, a drug that belongs to the lowering cholesterol molecule family of statins, has been shown to ameliorate endothelial functions and is widely used in patients with cardiovascular disorders.Methods
The effect of this compound on PRBC induced endothelial impairments was assessed using endothelial co-culture models.Results
Atorvastatin pre-treatment of EC was found to reduce the expression of adhesion molecules and P. falciparum cytoadherence, to protect cells against PRBC-induced apoptosis and to enhance endothelial monolayer integrity during co-incubation with parasites.Conclusions
These results might suggest a potential interest use of atorvastatin as a protective treatment to interfere with the pathophysiological cascades leading to severe malaria.7.
8.
Konstantin V. Kiselev Anna V. Turlenko Yuri N. Zhuravlev 《Plant Cell, Tissue and Organ Culture》2009,99(2):141-149
A somatic embryogenesis protocol for plant regeneration of northern red oak (Quercus rubra) was established from immature cotyledon explants. Embryogenic callus cultures were induced on Murashige and Skoog medium
(MS) containing 3% sucrose, 0.24% Phytagel™, and various concentrations of 2,4-dichlorophenoxyacetic acid (2,4-d) after 4 weeks of culture in darkness. A higher response (66%) of embryogenic callus was induced on 0.45 μM 2,4-d. Higher numbers of globular- (31), heart- (17), torpedo- (12), and cotyledon-stage (8) embryos per explant were obtained
by culturing embryogenic callus on MS with 3% sucrose, 0.24% Phytagel™, and devoid of growth regulators after 8 weeks culture
in darkness. Continuous sub-culturing of embryogenic callus on medium containing 2,4-d yielded only compact callus. Desiccation of embryos for 3 days in darkness at 25 ± 2°C followed by cold storage at 4°C in
darkness for 8 weeks favored embryo germination and development of plantlets. Cotyledon-stage embryos subjected to desiccation
and chilling treatment cultured on MS with 3% sucrose, 0.24 Phytagel™, 0.44 μM 6-benzylaminopurine (BA), and 0.29 μM gibberellic
acid germinated at a higher frequency (61%) than with 0.44 μM BA alone and control cultures. Germinated plantlets developed
a shoot and root, were acclimatized successfully, and maintained in a growth room for plantlet development. 相似文献
9.
Liliana Morales Paula Hernández Jacqueline Chaparro-Olaya 《Molecular biotechnology》2018,60(12):887-900
Constructs containing partial coding sequences of myosin A, myosin B, and glideosome-associated protein (50 kDa) of Plasmodium falciparum were used to challenge several strategies designed in order to improve the production and solubility of recombinant proteins in Escherichia coli. Assays were carried out inducing expression in a late log phase culture, optimizing the inductor concentration, reducing the growth temperature for induced cultures, and supplementing additives in the lysis buffer. In addition, recombinant proteins were expressed as fusion proteins with three different tags (6His, GST, and MBP) in four different E. coli strains. We found that the only condition that consistently produced soluble proteins was the use of MBP as a fusion tag, which became a valuable tool for detecting the proteins used in this study and did not caused any interference in protein–protein interaction assays (Far Western Blot). Besides, we found that BL21-pG-KJE8 strain did not improve the solubility of any of the recombinant protein produced, while the BL21-CodonPlus(DE3)-RIL strain improved the expression of some of them independent of the rare codon content. Proteins with rare codons occurring at high frequencies (»?10%) were expressed efficiently in strains that do not supplement tRNAs for these triplets. 相似文献
10.
11.
Fernanda Laroza Paganelli Eliana Gertrudes de Macedo Lemos Lúcia Maria Carareto Alves 《World journal of microbiology & biotechnology》2011,27(4):773-778
Polyhydroxyalkanoates (PHAs) are hydroxyalkanoate polymers that are produced and accumulate by many kinds of bacteria. These
polymers act as an energy store for bacteria. Polyhydroxybutyrate (PHB) is the most studied polymer in the PHA family. These
polymers have awakened interest in the environmental and industrial research areas because they are biodegradable and have
thermoplastic qualities, like polypropylene. In this work, we analyzed the PHB production in Bradyrhizobium sp., Rhizobium leguminosarum bv. phaseoli, and Rhizobium huautlense cultured with two different carbon sources. We did biochemical quantification of PHB production during the three phases of
growth. Moreover, these samples were used for RNA extraction and phbC gene expression analysis via real-time PCR. The bacteria showed different manner of growth, PHB accumulation and phbC gene expression when different quantity and quality of carbon sources were used. These results showed that under different
growth media conditions, the growth and metabolism of different species of bacteria were influenced. These differences reflect
the increase or decrease in PHB accumulation. 相似文献
12.
Background
Growth kinetic of Plasmodium falciparum in culture or in the host fall short of expected growth rate considering that there are 4 x 106/µL red blood cell (RBCs) available for invasion and about 16 merozoites growing in each infected RBC. This study determined whether apoptotic machinery is operable to keep the parasite population under check.Methods
A synchronized culture of P. falciparum (Dd2 strain) was initiated at 0.5% ring stage parasitaemia and kept under conditions not limiting for RBCs and nutrient by adjusting hematocrit to 5% at each schizogony and changing growth media daily. Parasite growth pattern and morphology was evaluated by blood smear microscopy and flow-cytometry using SYBR green. The apoptotic processes were evaluated for evidence of: DNA fragmentation by TUNEL, collapse of mitochondria membrane potential (ΔΨm) by TMRE, expression of metacaspse gene by RT-qPCR and by probing parasite proteins with anti-caspase antibodies.Results
From the seeding parasitaemia of 0.5%, the parasites doubled every 48 hours to a parasitaemia of 4%. Thereafter, the growth stagnated and the culture consistently crashed at about 6% parasitaemia. ΔΨm potential collapsed as the parasite density increased and DNA fragmentation increased steadily from 0.2% to ~6%. The expression of metacaspase gene and protein was observed in all stages, but their abundance was variable among the stages.Conclusion
These findings suggest existence of P. falciparum quorum sensing that keep the parasite population under check.13.
14.
Proteolytic degradation is the primary obstacle in the use of the yeast Pichia pastoris for the expression of recombinant proteins. During the production of a recombinant Plasmodium falciparum circumsporozoite protein in this system, the (NANP)
n
repeats region at the N-terminus were completely proteolytically degraded. To remove the potential proteolytic site within
the recombinant protein, different strategies were tried, including adjusting the cultivation conditions and mutating the
sequence at the junction of the repeat domain and C-terminal region, but the degradation continued. However, modification
of the N-terminal sequence by adding an epitope-based peptide to the N-terminus not only protected the repeat domain from
cleavage by native proteases during longer induction in the yeast host and purification process, but also stabilized this
recombinant protein emulsified with adjuvant ISA720 for at least 6 months. The results showed that proteolytic degradation
of the recombinant circumsporozoite protein produced in P. pastoris was amino acid sequence (NANP)-specific, and that this effect was likely dependent on the conformation of the recombinant
protein. 相似文献
15.
16.
Jai Shankar Singh Vaibhav Kumar Shukla Mansi Gujrati Ram Kumar Mishra Ashutosh Kumar 《Biomolecular NMR assignments》2017,11(1):17-20
One of the most debilitating diseases Malaria, in its different forms, is caused by protozoan of Plasmodium species. Deadliest among these forms is the “cerebral malaria” which is afflicted upon by Plasmodium falciparum. Plasmodium adopts numerous strategies including various post-translational modifications (PTMs) to infect and survive in the human host. These PTMs have proven their critical requirement in the Plasmodium biology. Recently, sumoylation has been characterized as one of the important PTMs and many of its putative substrates have been identified in Plasmodium. Sumoylation is the covalent attachment of SUMO protein to the substrate protein, which is mediated by an enzyme cascade involving activating (E1), conjugating (E2), and ligating enzymes (E3). Here, we report resonance assignment for 1H, 13C and 15N of Plasmodium falciparum SUMO (Pf-SUMO) protein determined by various 2D and 3D heteronuclear NMR experiments along with predicted secondary structures. 相似文献
17.
Patrícia Pimentel de Barros Fernanda Freire Rodnei Dennis Rossoni Juliana Campos Junqueira Antonio Olavo Cardoso Jorge 《Folia microbiologica》2017,62(4):317-323
Pathogenicity of Candida albicans is associated with its capacity switch from yeast-like to hyphal growth. The hyphal form is capable to penetrate the epithelial surfaces and to damage the host tissues. Therefore, many investigations have focused on mechanisms that control the morphological transitions of C. albicans. Recently, certain studies have showed that non-albicans Candida species can reduce the capacity of C. albicans to form biofilms and to develop candidiasis in animal models. Then, the objective of this study was to evaluate the effects of Candida krusei and Candida glabrata on the morphogenesis of C. albicans. Firstly, the capacity of reference and clinical strains of C. albicans in forming hyphae was tested in vitro. After that, the expression of HWP1 (hyphal wall protein 1) gene was determined by quantitative real-time PCR (polymerase chain reaction) assay. For both reference and clinical strains, a significant inhibition of the hyphae formation was observed when C. albicans was incubated in the presence of C. krusei or C. glabrata compared to the control group composed only by C. albicans. In addition, the culture mixed of C. albicans-C. krusei or C. albicans-C. glabrata reduced significantly the expression of HWP1 gene of C. albicans in relation to single cultures of this specie. In both filamentation and gene expression assays, C. krusei showed the higher inhibitory activity on the morphogenesis of C. albicans compared to C. glabrata. C. krusei and C. glabrata are capable to reduce the filamentation of C. albicans and consequently decrease the expression of the HWP1 gene. 相似文献
18.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes. 相似文献
19.
20.
Lee JH Moon YH Kim N Kim YM Kang HK Jung JY Abada E Kang SS Kim D 《Biotechnology letters》2008,30(4):749-754
The gene encoding sucrose phosphorylase (742sp) in Leuconostoc mesenteroides NRRL B-742 was cloned and expressed in Escherichia coli. The nucleotide sequence of the transformed 742sp comprised an ORF of 1,458 bp giving a protein with calculated molecular mass of 55.3 kDa. 742SPase contains a C-terminal amino acid sequence that is significantly different from those of other Leu. mesenteroides SPases. The purified 742SPase had a specific activity of 1.8 U/mg with a K
m of 3 mM with sucrose as a substrate; optimum activity was at 37°C and pH 6.7. The purified 742SPase transferred the glucosyl
moiety of sucrose to cytosine monophosphate (CMP).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献