Abstract:
:A major obstacle to studying the functions of particular gene products in the mouse-tick infectious cycle of Borrelia burgdorferi has been an inability to knock out genes in pathogenic strains. Here, we investigated conditions for site-directed mutagenesis in B31 MI, the low-passage-number, infectious B. burgdorferi strain whose genome was sequenced. We inactivated several plasmid and chromosomal genes in B31 MI and determined that clones carrying these mutations were not infectious for mice. However, we found extensive heterogeneity among clones and mutants derived from B31 MI based on colony phenotype, growth rate, plasmid content, protein profile, and transformability. Significantly, several B31 MI clones that were not subjected to mutagenesis but that lacked particular plasmids also exhibited defects at various stages in the infectious cycle. Therefore, the high degree of clonal polymorphism within B31 MI complicates the assessment of the contributions of individual genes to the observed phenotypes of the mutants. Our results indicate that B31 MI is not an appropriate strain background for genetic studies in infectious B. burgdorferi, and a well-defined isogenic clone is a prerequisite for targeted mutagenesis. To this end, we derived several wild-type clones from B31 MI that were infectious for mice, and gene inactivation was successful in one of these clones. Due to the instability of the genome with in vitro propagation, careful monitoring of plasmid content of derived mutants and complementation of inactivated genes will be crucial components of genetic studies with this pathogen.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Elias AF,Stewart PE,Grimm D,Caimano MJ,Eggers CH,Tilly K,Bono JL,Akins DR,Radolf JD,Schwan TG,Rosa Pdoi
10.1128/iai.70.4.2139-2150.2002keywords:
subject
Has Abstractpub_date
2002-04-01 00:00:00pages
2139-50issue
4eissn
0019-9567issn
1098-5522journal_volume
70pub_type
杂志文章abstract::Sera from certain animal species contain a substance(s) which binds hepatitis B surface antigen. The hepatitis B binding substance found in animals is not antibody, but appears to be a glycoprotein which reacted with antigen-coated beads and produced a "false positive" test for antibody. This glycoprotein could be sel...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.21.3.879-885.1978
更新日期:1978-09-01 00:00:00
abstract::Streptococcus sanguis 804 (NCTC 10904) was grown ih batch culture at constant pH. and the glucosyltransferase activity of the supernatant was assayed over a 40-h growth period. The optimum pH for enzyme production was 7.0 to 7.2. During growth of the culture, three reproducible phases of enzyme activity were observed....
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.15.1.50-58.1977
更新日期:1977-01-01 00:00:00
abstract::Oral inoculation of calves and steers with 10(10) CFU of Escherichia coli O157:H7 induced prompt and sustained increases in serum antibodies to O157 lipopolysaccharide. Neutralizing antibodies to verotoxin 1 also increased rapidly in most steers but more gradually in calves. None of the animals developed neutralizing ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.5.1879-1883.1996
更新日期:1996-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00917-19
更新日期:2020-03-23 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.1.230-236.1999
更新日期:1999-01-01 00:00:00
abstract::We have previously shown that Bacillus anthracis lethal toxin represses glucocorticoid receptor (GR) transactivation. We now report that repression of GR activity also occurs with the large clostridial toxins produced by Clostridium sordellii and C. difficile. This was demonstrated using a transient transfection assay...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00291-07
更新日期:2007-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00504-19
更新日期:2020-01-22 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.8.3841-3847.1998
更新日期:1998-08-01 00:00:00
abstract::Protective immunity to Plasmodium falciparum malaria acquired after natural exposure is largely antibody mediated. IgG-specific P. falciparum EMP1 (PfEMP1) proteins on the infected erythrocyte surface are particularly important. The transient antibody responses and the slowly acquired protective immunity probably refl...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01514-13
更新日期:2014-05-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00162-13
更新日期:2013-06-01 00:00:00
abstract::Random-bred mice were immunized with a nonliving antigen prepared from mixed-blood forms of Plasmodium berghei, strain NYU-2, in combination with Corynebacterium parvum and/or living BCG. A high proportion of intravenously immunized mice survived virulent challenge, but subcutaneous vaccination was less effective. Vac...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.22.3.798-803.1978
更新日期:1978-12-01 00:00:00
abstract::Protamines (salmine prepared from sperm DNA of salmon and clupeine from herring sperm), which are basic peptides rich in arginine, were found to inhibit the proteolytic activity of arginine-specific cysteine protease (RC-protease) from Porphyromonas gingivalis. Lineweaver-Burk plot analysis revealed that the protamine...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.9.4917-4920.1999
更新日期:1999-09-01 00:00:00
abstract::By crossed immunoelectrophoresis and Western blotting (immunoblotting), it was shown that Borrelia burgdorferi expresses the 60-kilodalton Common Antigen (CA) that is cross-reactive with an equivalent antigen in a wide range of remotely related bacteria. B. burgdorferi CA is strongly immunogenic. A B. burgdorferi geno...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.8.2047-2053.1988
更新日期:1988-08-01 00:00:00
abstract::Unmethylated CpG dinucleotide motifs present in bacterial genomes or synthetic oligodeoxynucleotides (ODNs) serve as strong immunostimulatory agents in mice, monkeys and humans. We determined the adjuvant effect of murine CpG ODN 1826 on the immunogenicity and protective efficacy of the Saccharomyces cerevisiae-expres...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.2.949-957.2004
更新日期:2004-02-01 00:00:00
abstract::Resequencing estA3, an allele of the methanol-soluble heat-stable enterotoxin of Escherichia coli showed that the proline triplet 19 is in fact an alanine codon; thus, estA alleles 3 and 4 were shown to be identical. Resequencing has also shown that the carboxy terminus of another allele, estA2, is not the previously ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.2.645-648.1989
更新日期:1989-02-01 00:00:00
abstract::3-O-methylmannose isolated from Coccidioides immitis was characterized by gas chromatographic comparison of derivatives with those of synthetic 3-O-methylmannose. Gas chromatographic behavior of three derivatives of the natural and synthetic sugars was identical. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.4.5.660-661.1971
更新日期:1971-11-01 00:00:00
abstract::In the present study, we have investigated the evolution and impact on virulence of a 350-kb genomic duplication present in the most recently evolved members of the Mycobacterium tuberculosis East Asian lineage. In a mouse model of infection, comparing HN878 subclones HN878-27 (no duplication) and HN878-45 (with the 3...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01791-14
更新日期:2014-07-01 00:00:00
abstract::Polymorphoneutrophils (PMNs) are important effector cells in host defense against pneumonia. However, PMNs can also induce inflammation and tissue damage. To investigate the contribution of PMNs to host defense against pneumococcal pneumonia, we determined the effect of the PMN-depleting rat monoclonal antibody RB6-8C...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01579-06
更新日期:2007-04-01 00:00:00
abstract::Murine embryo fibroblasts (MEF) were found to secrete tumor necrosis factor (TNF) in response to stimulation with endotoxin. Endotoxin-induced TNF production by MEF was inhibited by cycloheximide. However, reversal of the effect of this inhibitor on protein synthesis results in TNF being secreted in amounts equivalent...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.5.1630-1635.1993
更新日期:1993-05-01 00:00:00
abstract::Although Salmonella enterica serovar Typhimurium can undergo phase variation to alternately express two different types of flagellin subunit proteins, FljB or FliC, no biological function for this phenomenon has been described. In this investigation, we constructed phase-locked derivatives of S. enterica serovar Typhi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.5.3021-3030.2001
更新日期:2001-05-01 00:00:00
abstract::Vibrio cholerae accessory colonization factor genes (acfA, B, C, and D) are required for efficient intestinal colonization. Expression of acf genes is under the control of a regulatory cascade that also directs the synthesis of cholera toxin and proteins involved in the biogenesis of the toxin-coregulated pilus. The g...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.8.3289-3298.1994
更新日期:1994-08-01 00:00:00
abstract::We performed ex vivo experiments with Plasmodium falciparum-infected human placentas from primi- and multigravida women from Cameroon. All women, independent of their gravida status, had anti-chondroitin sulfate A (CSA) adhesion antibodies which cross-reacted with heterologous strains, such as FCR3 and Palo-Alto(FUP)1...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract::Herpes simplex virus type 1 (HSV-1) glycoprotein gC was purified by affinity chromatography with an immunosorbent column containing monoclonal antibody to HSV-1 gC, and its reactivity with rabbit antisera was measured by enzyme-linked immunosorbent assay and sodium dodecyl sulfate-polyacrylamide gel electrophoretic an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.41.2.482-487.1983
更新日期:1983-08-01 00:00:00
abstract::Rickettsia rickettsii and R. australis formed infectious antibody complexes when reacted with homologous convalescent serum. The addition of antiglobulin to these complexes showed neutralization of plaques proportional to the concentration of rickettsial immune serum. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.5.966-968.1974
更新日期:1974-05-01 00:00:00
abstract::The mechanism of complement-mediated killing of seven serum-sensitive Pseudomonas aeruginosa strains was examined. All seven strains were sensitive to the bactericidal activity of 20% pooled normal human serum (PNHS) containing magnesium EGTA, which blocks the classical complement pathway (CCP), or 20% PNHS preheated ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.3.632-639.1988
更新日期:1988-03-01 00:00:00
abstract::Fourteen freshly isolated strains of Streptococcus sanguis were obtained from the dental plaque of five healthy adults. Whole saliva was collected concomitant with the plaque isolates from the five subjects, and a second whole saliva sample was collected 10 weeks later. All possible combinations of the first five sali...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.26.3.1104-1110.1979
更新日期:1979-12-01 00:00:00
abstract::Acquired cellular immunity to infection with Mycobacterium tuberculosis is believed to reside in the capacity of mononuclear phagocytes of immunized animals to inhibit intracellular multiplication of the parasite. However, in macrophage tissue culture systems, it has been customary to employ streptomycin in the medium...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1970-01-01 00:00:00
abstract::Efficient utilization of heme as an iron (Fe) source by Bordetella avium requires bhuR, an Fe-regulated gene which encodes an outer membrane heme receptor. Upstream of bhuR is a 507-bp open reading frame, hereby designated rhuI (for regulator of heme uptake), which codes for a 19-kDa polypeptide. Whereas the 19-kDa po...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.11.6951-6961.2001
更新日期:2001-11-01 00:00:00
abstract::Blastomyces dermatitidis is a thermally induced dimorphic fungus capable of causing lung and systemic infections in immunocompetent animal hosts. With the publication of genomic sequences from three different strains of B. dermatitidis and the development of RNA interference as a gene-silencing tool, it has become pos...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01328-09
更新日期:2010-06-01 00:00:00
abstract::Previously we demonstrated that recombinant murine interleukin-12 (rmIL-12) administration can promote a primary Th1 response while suppressing the Th2 response in mice primed with 2,4, 6-trinitrophenyl-keyhole limpet hemocyanin (TNP-KLH). The present studies examined the capacity of rmIL-12 to drive a Th1 response to...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.5.2166-2171.1999
更新日期:1999-05-01 00:00:00