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1.
mtDNA diversity in rhesus monkeys reveals overestimates of divergence time and paraphyly with neighboring species 总被引:4,自引:0,他引:4
Reconstructions of the human-African great ape phylogeny by using
mitochondrial DNA (mtDNA) have been subject to considerable debate. One
confounding factor may be the lack of data on intraspecific variation. To
test this hypothesis, we examined the effect of intraspecific mtDNA
diversity on the phylogenetic reconstruction of another Plio- Pleistocene
radiation of higher primates, the fascicularis group of macaque (Macaca)
monkey species. Fifteen endonucleases were used to identify 10 haplotypes
of 40-47 restriction sites in M. mulatta, which were compared with similar
data for the other members of this species group. Interpopulational,
intraspecific mtDNA diversity was large (0.5%- 4.5%), and estimates of
divergence time and branching order incorporating this variation were
substantially different from those based on single representatives of each
species. We conclude that intraspecific mtDNA diversity is substantial in
at least some primate species. Consequently, without prior information on
the extent of genetic diversity within a particular species, intraspecific
variation must be assessed and accounted for when reconstructing primate
phylogenies. Further, we question the reliability of hominoid mtDNA
phylogenies, based as they are on one or a few representatives of each
species, in an already depauperate superfamily of primates.
相似文献
2.
Achiléa Lisboa Bittencourt Maria das Graças Santana Araujo Maria do Socorro Fontoura Paes 《Mycopathologia》1980,71(3):155-158
A case of a two-year-old boy with multiple subcutaneous lesions caused by Basidiobolus haptosporus is presented.The child had also a non-toxic familial goiter and clinical and radiological features of a pulmonary illness. The pulmonary manifestations only disappeared with the treatment with potassium iodide. The authors think that the pulmonary lesions must have arisen by direct spread of the fungus from the subcutaneous lesions of the chest. 相似文献
3.
A P Valente H Barrabin R V Jorge M C Paes H M Scofano 《Biochimica et biophysica acta》1990,1039(3):297-304
Preparations of sarcoplasmic reticulum vesicles, obtained according to the method of Eletr and Inesi (Biochim. Biophys. Acta (1972) 282, 174), contained both Mg2(+)-ATPase and Ca2+, Mg2(+)-ATPase activity. The two enzymes were solubilized by a mixture of digitonin and lysophosphatidylcholine and separated on a DEAE-cellulose column eluted with a discontinuous gradient of NaCl. The Mg2(+)-ATPase activity was eluted with 0.43 M NaCl. The Ca2+,Mg2(+)-ATPase was obtained by increasing the NaCl concentration of the elution medium to 0.40 M. The fraction eluted with 0.043 M NaCl was insensitive to micromolar concentrations of calcium, resistant to oligomycin, ouabain, orthovanadate and thiocyanate, and was inhibited by low concentrations of Triton X-100. The enzyme showed a single apparent Km for MgATP in the range of 0.2 mM and a Vm of 2.9 mumol Pi.min-1.mg-1 protein. Activity was maximal over a broad peak between pH 6.0-8.0. Hydrolysis of ATP was unaffected by dimethylsulfoxide concentrations up to 20% (v/v) and was inhibited at higher concentrations. The enzyme was not phosphorylated by either 32Pi or [gamma-32P]ATP at significant levels when compared with the Ca2+,Mg2(+)-ATPase in an EGTA-containing medium. The kinetic pattern of the Mg2(+)-ATPase was distinctly different from that of the Ca2+,Mg2(+)-ATPase under the same conditions. The fraction eluted from the DEAE-cellulose column was subjected to electrophoresis under non-denaturing conditions. Only one band with Mg2(+)-ATPase activity was detected. The Mg2(+)-ATPase migrated much slower than the Ca2+,Mg2(+)-ATPase under non-denaturing conditions, whereas both enzymes had a molecular mass of 105 kDa on SDS gel electrophoresis. 相似文献
4.
Comparative proteomic analysis of Xanthomonas citri ssp. citri periplasmic proteins reveals changes in cellular envelope metabolism during in vitro pathogenicity induction 下载免费PDF全文
Juliana Artier Flávia da Silva Zandonadi Flávia Maria de Souza Carvalho Bianca Alves Pauletti Adriana Franco Paes Leme Carolina Moretto Carnielli Heloisa Sobreiro Selistre‐de‐Araujo Maria Célia Bertolini Jesus Aparecido Ferro José Belasque Júnior Julio Cezar Franco de Oliveira Maria Teresa Marques Novo‐Mansur 《Molecular Plant Pathology》2018,19(1):143-157
Citrus canker is a plant disease caused by Gram‐negative bacteria from the genus Xanthomonas. The most virulent species is Xanthomonas citri ssp. citri (XAC), which attacks a wide range of citrus hosts. Differential proteomic analysis of the periplasm‐enriched fraction was performed for XAC cells grown in pathogenicity‐inducing (XAM‐M) and pathogenicity‐non‐inducing (nutrient broth) media using two‐dimensional electrophoresis combined with liquid chromatography‐tandem mass spectrometry. Amongst the 40 proteins identified, transglycosylase was detected in a highly abundant spot in XAC cells grown under inducing condition. Additional up‐regulated proteins related to cellular envelope metabolism included glucose‐1‐phosphate thymidylyltransferase, dTDP‐4‐dehydrorhamnose‐3,5‐epimerase and peptidyl‐prolyl cis–trans‐isomerase. Phosphoglucomutase and superoxide dismutase proteins, known to be involved in pathogenicity in other Xanthomonas species or organisms, were also detected. Western blot and quantitative real‐time polymerase chain reaction analyses for transglycosylase and superoxide dismutase confirmed that these proteins were up‐regulated under inducing condition, consistent with the proteomic results. Multiple spots for the 60‐kDa chaperonin and glyceraldehyde‐3‐phosphate dehydrogenase were identified, suggesting the presence of post‐translational modifications. We propose that substantial alterations in cellular envelope metabolism occur during the XAC infectious process, which are related to several aspects, from defence against reactive oxygen species to exopolysaccharide synthesis. Our results provide new candidates for virulence‐related proteins, whose abundance correlates with the induction of pathogenicity and virulence genes, such as hrpD6, hrpG, hrpB7, hpa1 and hrpX. The results present new potential targets against XAC to be investigated in further functional studies. 相似文献
5.
Chidananda Sulli Soma S. R. Banik Justin Schilling Allan Moser Xiaoxiao Xiang Riley Payne Antony Wanless Sharon H. Willis Cheryl Paes Joseph B. Rucker Benjamin J. Doranz 《Journal of virology》2013,87(19):10679-10686
The influenza virus M2 protein is a well-validated yet underexploited proton-selective ion channel essential for influenza virus infectivity. Because M2 is a toxic viral ion channel, existing M2 inhibitors have been discovered through live virus inhibition or medicinal chemistry rather than M2-targeted high-throughput screening (HTS), and direct measurement of its activity has been limited to live cells or reconstituted lipid bilayers. Here, we describe a cell-free ion channel assay in which M2 ion channels are incorporated into virus-like particles (VLPs) and proton conductance is measured directly across the viral lipid bilayer, detecting changes in membrane potential, ion permeability, and ion channel function. Using this approach in high-throughput screening of over 100,000 compounds, we identified 19 M2-specific inhibitors, including two novel chemical scaffolds that inhibit both M2 function and influenza virus infectivity. Counterscreening for nonspecific disruption of viral bilayer ion permeability also identified a broad-spectrum antiviral compound that acts by disrupting the integrity of the viral membrane. In addition to its application to M2 and potentially other ion channels, this technology enables direct measurement of the electrochemical and biophysical characteristics of viral membranes. 相似文献
6.
João H. C. Manfrão-Netto Enzo Bento Queiroz Ana C. de Oliveira Junqueira Antônio M. V. Gomes Daniel Gusmão de Morais Hugo Costa Paes Nádia Skorupa Parachin 《Journal of applied microbiology》2022,132(2):822-840
Hyaluronic acid (HA) is a biopolymer of repeating units of glucuronic acid and N-acetylglucosamine. Its market was valued at USD 8.9 billion in 2019. Traditionally, HA has been obtained from rooster comb-like animal tissues and fermentative cultures of attenuated pathogenic streptococci. Various attempts have been made to engineer a safe micro-organism for HA synthesis; however, the HA titres obtained from these attempts are in general still lower than those achieved by natural, pathogenic producers. In this scenario, ways to increase HA molecule length and titres in already constructed strains are gaining attention in the last years, but no recent publication has reviewed the main genetic strategies applied to improve HA production on heterologous hosts. In light of that, we hereby compile the advances made in the engineering of micro-organisms to improve HA synthesis. 相似文献
7.
Daniela C. Granato Mariana R. Zanetti Rebeca Kawahara Sami Yokoo Romênia R. Domingues Annelize Z. Arag?o Michelle Agostini Marcelo F. Carazzolle Ramon O. Vidal Isadora L. Flores Johanna Korvala Nilva K. Cervigne Alan R. S. Silva Ricardo D. Coletta Edgard Graner Nicholas E. Sherman Adriana F. Paes Leme 《PloS one》2014,9(5)
Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules. 相似文献
8.
Patrícia M. Paes de Sousa Sofia R. Pauleta M. Lurdes Simões Gonçalves Graham W. Pettigrew Isabel Moura José J. G. Moura Margarida M. Correia dos Santos 《Journal of biological inorganic chemistry》2011,16(2):209-215
In this work it is demonstrated that the characterization of c-type haem containing proteins by electrochemical techniques needs to be cautiously performed when using pyrolytic graphite
electrodes. An altered form of the cytochromes, which has a redox potential 300 mV lower than that of the native state and
displays peroxidatic activity, can be induced by interaction with the pyrolytic graphite electrode. Proper control experiments
need to be performed, as altered conformations of the enzymes containing c-type haems can show activity towards the enzyme substrate. The work was focused on the study of the activation mechanism
and catalytic activity of cytochrome c peroxidase from Paracoccus
pantotrophus. The results could only be interpreted with the assignment of the observed non-turnover and catalytic signals to a non-native
conformation state of the electron-transferring haem. The same phenomenon was detected for Met–His monohaem cytochromes (mitochondrial
cytochrome c and Desulfovibrio
vulgaris cytochrome c-553), as well as for the bis-His multihaem cytochrome c
3 from Desulfovibrio
gigas, showing that this effect is independent of the axial coordination of the c-type haem protein. Thus, the interpretation of electrochemical signals of c-type (multi)haem proteins at pyrolytic graphite electrodes must be carefully performed, to avoid misassignment of the signals
and incorrect interpretation of catalytic intermediates. 相似文献
9.
Giselle Pidde-Queiroz Fábio Carlos Magnoli Fernanda C. V. Portaro Solange M. T. Serrano Aline Soriano Lopes Adriana Franco Paes Leme Carmen W. van den Berg Denise V. Tambourgi 《PLoS neglected tropical diseases》2013,7(10)
Background
Snake Venom Metalloproteinases (SVMPs) are amongst the key enzymes that contribute to the high toxicity of snake venom. We have recently shown that snake venoms from the Bothrops genus activate the Complement system (C) by promoting direct cleavage of C-components and generating anaphylatoxins, thereby contributing to the pathology and spread of the venom. The aim of the present study was to isolate and characterize the C-activating protease from Bothrops pirajai venom.Results
Using two gel-filtration chromatography steps, a metalloproteinase of 23 kDa that activates Complement was isolated from Bothrops pirajai venom. The mass spectrometric identification of this protein, named here as C-SVMP, revealed peptides that matched sequences from the P-I class of SVMPs. C-SVMP activated the alternative, classical and lectin C-pathways by cleaving the α-chain of C3, C4 and C5, thereby generating anaphylatoxins C3a, C4a and C5a. In vivo, C-SVMP induced consumption of murine complement components, most likely by activation of the pathways and/or by direct cleavage of C3, leading to a reduction of serum lytic activity.Conclusion
We show here that a P-I metalloproteinase from Bothrops pirajai snake venom activated the Complement system by direct cleavage of the central C-components, i.e., C3, C4 and C5, thereby generating biologically active fragments, such as anaphylatoxins, and by cleaving the C1-Inhibitor, which may affect Complement activation control. These results suggest that direct complement activation by SVMPs may play a role in the progression of symptoms that follow envenomation. 相似文献10.
Daniela C. Granato Leandro X. Neves Luciana D. Trino Carolina M. Carnielli Ariane F.B. Lopes Sami Yokoo Bianca A. Pauletti Romênia R. Domingues Jamile O. Sá Gabriella Persinoti Douglas A.A. Paixão César Rivera Fabio M. de Sá Patroni Geizecler Tommazetto Alan R. Santos-Silva Márcio A. Lopes Gilberto de Castro Thaís B. Brandão Adriana F. Paes Leme 《Biochimica et Biophysica Acta - Proteins and Proteomics》2021,1869(8):140659
Saliva is a biofluid that maintains the health of oral tissues and the homeostasis of oral microbiota. Studies have demonstrated that Oral squamous cell carcinoma (OSCC) patients have different salivary microbiota than healthy individuals. However, the relationship between these microbial differences and clinicopathological outcomes is still far from conclusive. Herein, we investigate the capability of using metagenomic and metaproteomic saliva profiles to distinguish between Control (C), OSCC without active lesion (L0), and OSCC with active lesion (L1) patients. The results show that there are significantly distinct taxonomies and functional changes in L1 patients compared to C and L0 patients, suggesting compositional modulation of the oral microbiome, as the relative abundances of Centipeda, Veillonella, and Gemella suggested by metagenomics are correlated with tumor size, clinical stage, and active lesion. Metagenomics results also demonstrated that poor overall patient survival is associated with a higher relative abundance of Stenophotromonas, Staphylococcus, Centipeda, Selenomonas, Alloscordovia, and Acitenobacter. Finally, compositional and functional differences in the saliva content by metaproteomics analysis can distinguish healthy individuals from OSCC patients. In summary, our study suggests that oral microbiota and their protein abundance have potential diagnosis and prognosis value for oral cancer patients. Further studies are necessary to understand the role of uniquely detected metaproteins in the microbiota of healthy and OSCC patients as well as the crosstalk between saliva host proteins and the oral microbiome present in OSCC. 相似文献