Abstract:
:The intraerythrocytic apicomplexan Babesia microti, the primary causative agent of human babesiosis, is a major public health concern in the United States and elsewhere. Apicomplexans utilize a multiprotein complex that includes a type I membrane protein called apical membrane antigen 1 (AMA1) to invade host cells. We have isolated the full-length B. microti AMA1 (BmAMA1) gene and determined its nucleotide sequence, as well as the amino acid sequence of the AMA1 protein. This protein contains an N-terminal signal sequence, an extracellular region, a transmembrane region, and a short conserved cytoplasmic tail. It shows the same domain organization as the AMA1 orthologs from piroplasm, coccidian, and haemosporidian apicomplexans but differs from all other currently known piroplasmida, including other Babesia and Theileria species, in lacking two conserved cysteines in highly variable domain III of the extracellular region. Minimal polymorphism was detected in BmAMA1 gene sequences of parasite isolates from six babesiosis patients from Nantucket. Immunofluorescence microscopy studies showed that BmAMA1 is localized on the cell surface and cytoplasm near the apical end of the parasite. Native BmAMA1 from parasite lysate and refolded recombinant BmAMA1 (rBmAMA1) expressed in Escherichia coli reacted with a mouse anti-BmAMA1 antibody using Western blotting. In vitro binding studies showed that both native BmAMA1 and rBmAMA1 bind to human red blood cells (RBCs). This binding is trypsin and chymotrypsin treatment sensitive but neuraminidase independent. Incubation of B. microti parasites in human RBCs with a mouse anti-BmAMA1 antibody inhibited parasite growth by 80% in a 24-h assay. Based on its antigenically conserved nature and potential role in RBC invasion, BmAMA1 should be evaluated as a vaccine candidate.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Moitra P,Zheng H,Anantharaman V,Banerjee R,Takeda K,Kozakai Y,Lepore T,Krause PJ,Aravind L,Kumar Sdoi
10.1128/IAI.00168-15subject
Has Abstractpub_date
2015-10-01 00:00:00pages
3890-901issue
10eissn
0019-9567issn
1098-5522pii
IAI.00168-15journal_volume
83pub_type
杂志文章abstract::The infection of HeLa 229 cells in monolayer culture with trachoma (B/TW-5/OT) and lymphogranuloma venereum (LGV) (L2/434/Bu) organism was studied in terms of two parameters: radioactivity counts of cell-associated tritium labeled organisms at the initial stage of inoculation for measurement of attachment, and inclusi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.13.4.1103-1109.1976
更新日期:1976-04-01 00:00:00
abstract::Vibrio cholerae responds to environmental changes by altering the protein composition of its outer membrane. In rich medium, V. cholerae expresses almost exclusively the outer membrane porin OmpU, whereas in minimal medium, OmpT is the dominant porin. The supplementation of a minimal medium with a mixture of asparagin...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05851-11
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.3.1330-1342.2005
更新日期:2005-03-01 00:00:00
abstract::Autotransporters of gram-negative bacteria are single-peptide secretion systems that consist of a functional N-terminal alpha-domain ("passenger") fused to a C-terminal beta-domain ("translocator"). How passenger proteins are translocated through the outer membrane has not been resolved, and at present essentially thr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.7.3851-3859.2005
更新日期:2005-07-01 00:00:00
abstract::Radial immunodiffusion procedures have been developed for testing bovine sera for the presence of antibody activity against three foot-and-mouth disease virus types and a virus infection-associated antigen. Reactions with virus antigens were obtained as early as 4 days after infection, and the virus type causing the r...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.5.2.227-231.1972
更新日期:1972-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05511-11
更新日期:2012-03-01 00:00:00
abstract::Staphylococcus aureus experimental endocarditis relies on sequential fibrinogen binding (for valve colonization) and fibronectin binding (for endothelial invasion) conferred by peptidoglycan-attached adhesins. Fibronectin-binding protein A (FnBPA) reconciles these two properties--as well as elastin binding--and promot...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00405-08
更新日期:2008-08-01 00:00:00
abstract::Fractionation of the culture medium showed that Streptococcus salivarius ATCC 25975 secreted a glucosyltransferase (Gtf) that was primer independent. On the basis of this observation, a gene library of S. salivarius chromosomal DNA cloned into lambda L47.1 was screened for a gene(s) coding for such an activity. As a r...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.2.609-621.1995
更新日期:1995-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.12.4661-4668.1995
更新日期:1995-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.8.4512-4520.2004
更新日期:2004-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.3.1055-1060.1992
更新日期:1992-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02269-14
更新日期:2015-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.38.2.694-698.1982
更新日期:1982-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.2.439-444.1977
更新日期:1977-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.5.934-938.1974
更新日期:1974-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.12.6670-6676.2000
更新日期:2000-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1096-1100.1988
更新日期:1988-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00401-17
更新日期:2017-11-17 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.5.1210-1216.1990
更新日期:1990-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.10.4138-4142.1995
更新日期:1995-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.3.1364-1373.2004
更新日期:2004-03-01 00:00:00
abstract::Virulent Treponema pallidum organisms, extracted from infected rabbit testes, were subjected to velocity sedimentation in discontinuous gradients of Hypaque, a high density, low viscosity material. After centrifugation of extracts at 20 C for 45 min at 100,000 x g, treponemes separated into two distinct bands based up...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.10.5.1062-1067.1974
更新日期:1974-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.11.4793-4800.1993
更新日期:1993-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00224-15
更新日期:2015-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2012-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.4.2129-2134.2000
更新日期:2000-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.5.2051-2057.1994
更新日期:1994-05-01 00:00:00
abstract::Mutant cultures that lacked the ability to produce filamentous hemagglutinin were obtained by UV irradiation of Bordetella pertussis strain 18-323. Various biological activities of these mutants were compared with those of the parent culture. It was found that the leukocytosis-promoting, histamine-sensitizing, and mou...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.35.3.1018-1023.1982
更新日期:1982-03-01 00:00:00
abstract::We examined the effect of protein kinase C (PKC) activation on the cyclic GMP response to heat-stable enterotoxin (STa) in a colonic carcinoma intestinal epithelial cell line, T84 cells. Our results demonstrate that the active phorbol ester analog, phorbol dibutyrate, but not the inactive alpha-phorbol dibutyrate, act...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.5.1402-1407.1990
更新日期:1990-05-01 00:00:00
abstract::Inbred BALB/c mice were either immunized with Triton X-100-extracted antigens of blood-stage Plasmodium yoelii or infected with P. yoelii and cured in three successive schedules. Whereas the immunized BALB/c became only partially protected from subsequent challenge infection with blood-stage P. yoelii, the convalescen...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.11.3909-3916.1991
更新日期:1991-11-01 00:00:00