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1.
Wagner MA Eschenbrenner M Horn TA Kraycer JA Mujer CV Hagius S Elzer P DelVecchio VG 《Proteomics》2002,2(8):1047-1060
Brucella melitensis is a facultative intracellular bacterial pathogen that causes brucellosis, a zoonotic disease primarily infecting sheep and goats, characterized by undulant fever, arthritic pain and other neurological disorders in humans. A comprehensive proteomic study of strain 16M was conducted to identify and characterize the proteins expressed in laboratory-grown culture. Using overlapping narrow range immobilized pH gradient strips for two-dimensional gel electrophoresis, 883 protein spots were detected between pH 3.5 and 11. The average isoelectric point and molecular weight values of the detected spots were 5.22 and 46.5 kDa, respectively. Of the 883 observed protein spots, 440 have been identified by matrix-assisted laser desorption/ionization-mass spectrometry. These proteins represent 187 discrete open reading frames (ORFs) or 6% of the predicted 3197 ORFs contained in the genome. The corresponding ORFs of the identified proteins are distributed evenly between each of the two circular B. melitensis chromosomes, indicating that both replicons are functionally active. The presented proteome map lists those protein spots identified to date in this study. This map may serve as a baseline reference for future proteomic studies aimed at the definition of biochemical pathways associated with stress responses, host specificity, pathogenicity and virulence. It will also assist in characterization of global proteomic effects in gene-knockout mutants. Ultimately, it may aid in our overall understanding of the cell biology of B. melitensis, an important bacterial pathogen. 相似文献
2.
Marchesini MI Connolly J Delpino MV Baldi PC Mujer CV DelVecchio VG Comerci DJ 《PloS one》2011,6(12):e28480
Choloylglycine hydrolase (CGH, E.C. 3.5.1.24) is a conjugated bile salt hydrolase that catalyses the hydrolysis of the amide bond in conjugated bile acids. Bile salt hydrolases are expressed by gastrointestinal bacteria, and they presumably decrease the toxicity of host's conjugated bile salts. Brucella species are the causative agents of brucellosis, a disease affecting livestock and humans. CGH confers Brucella the ability to deconjugate and resist the antimicrobial action of bile salts, contributing to the establishment of a successful infection through the oral route in mice. Additionally, cgh-deletion mutant was also attenuated in intraperitoneally inoculated mice, which suggests that CGH may play a role during systemic infection other than hydrolyzing conjugated bile acids. To understand the role CGH plays in B. abortus virulence, we infected phagocytic and epithelial cells with a cgh-deletion mutant (Δcgh) and found that it is defective in the internalization process. This defect along with the increased resistance of Δcgh to the antimicrobial action of polymyxin B, prompted an analysis of the cell envelope of this mutant. Two-dimensional electrophoretic profiles of Δcgh cell envelope-associated proteins showed an altered expression of Omp2b and different members of the Omp25/31 family. These results were confirmed by Western blot analysis with monoclonal antibodies. Altogether, the results indicate that Brucella CGH not only participates in deconjugation of bile salts but also affects overall membrane composition and host cell internalization. 相似文献
3.
Proteomic analysis of Brucella abortus cell envelope and identification of immunogenic candidate proteins for vaccine development 总被引:1,自引:0,他引:1
Connolly JP Comerci D Alefantis TG Walz A Quan M Chafin R Grewal P Mujer CV Ugalde RA DelVecchio VG 《Proteomics》2006,6(13):3767-3780
Brucella abortus is the etiologic agent of bovine brucellosis and causes a chronic disease in humans known as undulant fever. In livestock the disease is characterized by abortion and sterility. Live, attenuated vaccines such as S19 and RB51 have been used to control the spread of the disease in animals; however, they are considered unsafe for human use and they induce abortion in pregnant cattle. For the development of a safer and equally efficacious vaccine, immunoproteomics was utilized to identify novel candidate proteins from B. abortus cell envelope (CE). A total of 163 proteins were identified using 2-DE with MALDI-TOF MS and LC-MS/MS. Some of the major protein components include outer-membrane protein (OMP) 25, OMP31, Omp2b porin, and 60 kDa chaperonin GroEL. 2-DE Western blot analyses probed with antiserum from bovine and a human patient infected with Brucella identified several new immunogenic proteins such as fumarate reductase flavoprotein subunit, F0F1-type ATP synthase alpha subunit, and cysteine synthase A. The elucidation of the immunome of B. abortus CE identified a number of candidate proteins for developing vaccines against Brucella infection in bovine and humans. 相似文献
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α-d-galactosidase (α-d-galactoside galactohydrolase, EC 3.2.1.22) activity in the normal endosperm increased with age continually up to endosperm maturity. In contrast, makapuno α-d-galactosidase was hardly detected in almost all stages of development except the last, where its activity was 8300-fold lower as compared to the normal. The possible role of α-d-galactosidase in the formation of the makapuno endosperm is discussed. 相似文献
6.
The warm-season perennial switchgrass (Panicum virgatum) is a candidate bioenergy crop. To be successful, switchgrass production must be maintained on low-quality landscapes with minimal inputs while facing future climates that are expected to be more extreme and more variable. We propose that antecedent rainfall constrains how plants respond to drought, as well as subsequently recover from drought. To test this idea, we examined how six switchgrass genotypes responded to a 1-year severe drought and then recovered under normal rainfall in the following year. These plants had previously grown for 3 years under a range of dry to wet rainfall levels in a shallow-soil common garden with no fertilizer. Plants previously exposed to drought produced less biomass, and basal area after the severe drought was relieved compared to previously well-watered plants. In addition, there were legacy effects caused by plant size: plants that were larger pre-drought were more likely to survive the severe drought, and plants that were larger during the severe drought recovered more biomass, basal area, and tillers post-drought. Although genotypes differed somewhat in their responses, the size constraint was consistent across genotypes. These findings suggest that we can establish more drought-resilient switchgrass stands by, for example, planning for initial irrigation or planting during a wet year to allow plants to grow larger prior to experiencing drought. Additional studies are needed to understand whether these rainfall and size legacies persist or are transient. 相似文献
7.
Sami J Savio Lara CV Harrison Tiina Luukkaala Tomi Heinonen Prasun Dastidar Seppo Soimakallio Hannu J Eskola 《Biomedical engineering online》2010,9(1):60
Background
The accuracy of texture analysis in clinical evaluation of magnetic resonance images depends considerably on imaging arrangements and various image quality parameters. In this paper, we study the effect of slice thickness on brain tissue texture analysis using a statistical approach and classification of T1-weighted images of clinically confirmed multiple sclerosis patients. 相似文献8.
Transformed tissues can be efficiently selected with the help of selectable markers. We studied the influence of genotype, culture medium, and chemical nature of selectable markers on the callus formation of sunflower ( Helianthus annuus L.) hypocotyl explants during the selection process. Kanamycin was found not to be a suitable marker for sunflower transformation, while paromomycin and phosphinotri-cin are both useful. Because the mechanism of action of these inhibitors is intimately connected with the physiological reactions of the cultured tissues, we investigated the influence of key media components on the efficiency of selection of transformed callus on phosphinotricin. Auxin, cytokinin, and gibberellic acid, as well as nitrate concentration, all had a strong influence on the spontaneous resistance of untrans-formed sunflower hypocotyl explants against this herbicide. The number of transformed cells varied in function of the growth regulator balance. Possible reasons for this media dependence are discussed. 相似文献
9.
José Rodrigues Coura Pedro Albajar Vi?as Angela CV Junqueira 《Memórias do Instituto Oswaldo Cruz》2014,109(7):856-862
Chagas disease is maintained in nature through the interchange of three cycles: the
wild, peridomestic and domestic cycles. The wild cycle, which is enzootic, has
existed for millions of years maintained between triatomines and wild mammals. Human
infection was only detected in mummies from 4,000-9,000 years ago, before the
discovery of the disease by Carlos Chagas in 1909. With the beginning of
deforestation in the Americas, two-three centuries ago for the expansion of
agriculture and livestock rearing, wild mammals, which had been the food source for
triatomines, were removed and new food sources started to appear in peridomestic
areas: chicken coops, corrals and pigsties. Some accidental human cases could also
have occurred prior to the triatomines in peridomestic areas. Thus, triatomines
progressively penetrated households and formed the domestic cycle of Chagas disease.
A new epidemiological, economic and social problem has been created through the
globalisation of Chagas disease, due to legal and illegal migration of individuals
infected by Trypanosoma cruzi or presenting Chagas disease in its
varied clinical forms, from endemic countries in Latin America to non-endemic
countries in North America, Europe, Asia and Oceania, particularly to the United
States of America and Spain. The main objective of the present paper was to present a
general view of the interchanges between the wild, peridomestic and domestic cycles
of the disease, the development of T. cruzi among triatomine, their
domiciliation and control initiatives, the characteristics of the disease in
countries in the Americas and the problem of migration to non-endemic countries. 相似文献
10.
Sharif Chowdhury Jason Lloyd-Price Olli-Pekka Smolander Wayne CV Baici Timothy R Hughes Olli Yli-Harja Gordon Chua Andre S Ribeiro 《BMC systems biology》2010,4(1):143