Abstract:
:The Corynebacterium diphtheriae hmuO gene encodes a heme oxygenase that is involved in the utilization of heme as an iron source. Transcription of hmuO is activated by heme or hemoglobin and repressed by iron and DtxR. Previous studies with Escherichia coli showed that heme-dependent transcriptional activation of an hmuO promoter-lacZ fusion was dependent on the cloned C. diphtheriae chrA and chrS genes (chrAS), which encode the response regulator and sensor kinase, respectively, of a two-component signal transduction system. In this study, nonpolar deletions in the chrAS genes were constructed on the chromosome of C. diphtheriae. Mutations in chrAS resulted in marked reduction in heme-dependent transcription of hmuO, which indicates that the ChrA/S system is a key regulator at the hmuO promoter. However, low but significant levels of heme-specific transcriptional activity were observed at the hmuO promoter in the chrAS mutants, suggesting that an additional heme-dependent activator is involved in hmuO expression. The chrAS mutants were also sensitive to heme, which was observed only in stationary-phase cultures and correlated with reduced cell viability. The heme sensitivity of the mutants was not due to reduced expression of hmuO, and these results suggest that additional factors controlled by the ChrA/S system may be involved in protection against heme toxicity. Transcriptional analysis of the chrAS operon revealed that it was not autoregulated or affected by iron or heme levels.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Bibb LA,King ND,Kunkle CA,Schmitt MPdoi
10.1128/IAI.73.11.7406-7412.2005keywords:
subject
Has Abstractpub_date
2005-11-01 00:00:00pages
7406-12issue
11eissn
0019-9567issn
1098-5522pii
73/11/7406journal_volume
73pub_type
杂志文章abstract::Corynebacterium renale type I (strain 115), 1.7 X 10(7) to 4.5 X 10(7) organisms, introduced intravenously into mice disappeared from the blood less than 24 h after inoculation and did not produce pyelonephritis. The same strain, 1 X 10(7) to 5 X 10(7) organisms, inoculated into the urinary bladder of mice was not rec...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.1.263-267.1977
更新日期:1977-04-01 00:00:00
abstract::Three strains of Lactobacillus, identified as Lactobacillus acidophilus, Lactobacillus gasseri, and Lactobacillus jensenii, were selected from among 70 isolates from the vaginas of healthy premenopausal women for properties relevant to mucosal colonization or antagonism. All three self-aggregated and adhered to epithe...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.5.1985-1989.1998
更新日期:1998-05-01 00:00:00
abstract::The role of gamma-delta T cells in host resistance to Chlamydia trachomatis was characterized by using a murine model of pneumonia caused by the mouse pneumonitis agent (MoPn), murine C. trachomatis. At days 3 and 7 after infection, gamma-delta T-cell-deficient knockout mice had significantly higher levels of MoPn in ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.9.3916-3919.1996
更新日期:1996-09-01 00:00:00
abstract::Genetic resistance to lethal infection with Rickettsia tsutsugamushi was studied in over 30 inbred strains, inbred hybrids, and outbred stocks of mice. Inbred mice infected intraperitoneally with the Gilliam strain of R. tsutsugamushi showed three patterns of response: susceptible (A/HeJ, C3H/HeDub, C3H/HeJ, C3H/HeN, ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.19.2.583-588.1978
更新日期:1978-02-01 00:00:00
abstract::Studies concerned with the mechanisms responsible for relative resistance or susceptibility of strains of inbred mice to Trypanosoma musculi infections are presented. Treatment with 400 rads of ionizing radiation, silica dust, or trypan blue (reticuloendothelial blocking agents) rendered C3H mice unable to control the...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.6.1647-1655.1989
更新日期:1989-06-01 00:00:00
abstract::Yersinia pestis, the agent of plague, has arisen from a less virulent pathogen, Yersinia pseudotuberculosis, by a rapid evolutionary process. Although Y. pestis displays a large number of virulence phenotypes, it is not yet clear which of these phenotypes descended from Y. pseudotuberculosis and which were acquired in...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.10.5892-5899.2003
更新日期:2003-10-01 00:00:00
abstract::Rickettsia rickettsii infection of endothelial cells is manifested in very distinctive changes in cell morphology, consisting of extensive dilatation of the membranes of the endoplasmic reticulum and outer nuclear envelope and blebbing of the plasma membrane, as seen by transmission electron microscopy (D. J. Silverma...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.5.2290-2299.1998
更新日期:1998-05-01 00:00:00
abstract::Staphylococcus aureus is an important opportunistic pathogen and is the etiological agent of many hospital- and community-acquired infections. The golden pigment, staphyloxanthin, of S. aureus colonies distinguishes it from other staphylococci and related Gram-positive cocci. Staphyloxanthin is the product of a series...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00838-16
更新日期:2017-01-26 00:00:00
abstract::Salmonella species utilize type III secretion systems (T3SSs) to translocate effectors into the cytosol of mammalian host cells, subverting cell signaling and facilitating the onset of gastroenteritis. In this study, we compared a draft genome assembly of Salmonella enterica subsp. salamae strain 3588/07 against the g...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00704-16
更新日期:2016-11-18 00:00:00
abstract::Alveolar bone resorption can be induced in specific-pathogen-free mice by oral infection with Porphyromonas gingivalis (P. J. Baker, R. T. Evans, and D. C. Roopenian, Arch. Oral Biol. 39:1035-1040, 1994). Here we used a mouse strain, C57BL/6J, which is relatively resistant to P. gingivalis-induced bone loss to examine...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.6.3103-3107.2000
更新日期:2000-06-01 00:00:00
abstract::Antibodies against the class 4 outer membrane protein (OMP) from Neisseria meningitidis have been purified from sera from vaccinees immunized with the Norwegian meningococcal group B outer membrane vesicle vaccine. The human sera and purified antibodies reacted strongly with the class 4 OMP in immunoblots, whereas exp...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.3.1267-1276.1999
更新日期:1999-03-01 00:00:00
abstract::Mice were inoculated with Legionella pneumophila via an intratracheal route to establish an experimental model of infection. Lung lavage fluid obtained from infected mice contained a cytolytic factor identified as tumor necrosis factor (TNF). Peak levels of TNF were produced at about 24 h postinfection and rapidly dec...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.2.433-437.1987
更新日期:1987-02-01 00:00:00
abstract::A GroEL-like protein from Bordetella pertussis was purified. This protein was found to have the tetradecameric subunit structure typical of the GroEL family of proteins and to contain epitopes similar to those of other members of this family, including a human GroEL-like protein. Active immunization of neonatal mice w...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.4.1417-1422.1991
更新日期:1991-04-01 00:00:00
abstract::Two enteropathogenic strains of Escherichia coli (EEC) differed from a nonenteropathogenic strain of E. coli (NEEC) in their association with porcine small intestinal epithelium. The EEC characteristically were found along villi from tip to base and contiguous to the brush border. They were not in crypts. In contrast,...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.5.4.595-605.1972
更新日期:1972-04-01 00:00:00
abstract::The purpose of these experiments was to study the early response of mouse foot pads to Mycobacterium leprae. To accomplish this, mice were inoculated in both foot pads with large and small numbers of organisms. The animals were sacrificed at intervals from 2 hr to 27 days after inoculation. The microscopical results, ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.7.1.76-85.1973
更新日期:1973-01-01 00:00:00
abstract::An LT-B-ST (LT-B/ST) fusion peptide was constructed by genetically joining the 5' terminus of a synthetic gene coding for the heat-stable enterotoxin (ST) of Escherichia coli to the 3' terminus of the gene coding for the binding subunit of the heat-labile enterotoxin (LT-B) of E. coli. An eight-amino-acid, proline-con...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.11.4629-4636.1993
更新日期:1993-11-01 00:00:00
abstract::Vitamin D(3) (1,25-dihydroxycholecalciferol) induced the phagocyte oxidative burst and intracellular killing of Salmonella enterica serovar Typhimurium in a phosphatidylinositol 3-kinase-dependent manner. The antimicrobial effect was more pronounced for Salmonella SodCI and SodCII mutants, confirming the role of the p...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.9.5312-5315.2002
更新日期:2002-09-01 00:00:00
abstract::Leptospira interrogans is an important mammalian pathogen. Transmission from an environmental source requires adaptations to a range of new environmental conditions in the organs and tissues of the infected host. Since many pathogenic bacteria utilize temperature to discern their environment and regulate the synthesis...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.1.400-404.2001
更新日期:2001-01-01 00:00:00
abstract::The response to reinfection with Ethiopian Leishmania donovani was evaluated in genetically determined noncure (H-2d) B10.D2 mice that are able to resolve infection due to sublethal irradiation pretreatment after inoculation with a low parasite dose and in C57BL/10 mice that demonstrate the genetically determined cure...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.9.2892-2899.1989
更新日期:1989-09-01 00:00:00
abstract::Interleukin-18 (IL-18) is a proinflammatory cytokine that plays an important role in natural killer cell activation and the T helper 1 (Th1) cell response, particularly in collaboration with IL-12. Since Th1 cells play a pivotal role in the host defense against infection with intracellular microbes, such as Leishmania...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.5.2449-2456.2000
更新日期:2000-05-01 00:00:00
abstract::The selC tRNA gene is a common site for the insertion of pathogenicity islands in a variety of bacterial enteric pathogens. We demonstrate here that Escherichia coli that produces Shiga toxin 2d and does not harbor the locus of enterocyte effacement (LEE) contains, instead, a novel genomic island. In one representativ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.11.6863-6873.2001
更新日期:2001-11-01 00:00:00
abstract::Citrate is a ubiquitous compound and can be utilized by many bacterial species, including enteric pathogens, as a carbon and energy source. Genes involved in citrate utilization have been extensively studied in some enteric bacteria, such as Klebsiella pneumoniae; however, their role in pathogenesis is still not clear...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00746-18
更新日期:2019-02-21 00:00:00
abstract::Various pathogenic bacteria with the capacity to live within eukaryotic cells activate an apoptotic program in infected host cells. Induction of apoptosis by Listeria monocytogenes in murine dendritic cells and hepatocytes has been described. Here we address the questions of whether and how the pathogen kills macropha...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.10.4075-4081.1997
更新日期:1997-10-01 00:00:00
abstract::Antibodies against feline leukemia virus (FeLV) and the feline oncornavirus-associated cell membrane antigen (FOCMA) were transferred from pregnant cats to their suckling kittens. All of these kittens were protected against infection and oncogenesis by virulent FeLV when challenged at 2 weeks of age. Suckling kittens ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.16.1.54-59.1977
更新日期:1977-04-01 00:00:00
abstract::Tuberculosis is rising in the developing world due to poor health care, human immunodeficiency virus type 1 infection, and the low protective efficacy of the Mycobacterium bovis BCG vaccine. A new vaccination strategy that could protect adults in the developing world from tuberculosis could have a huge impact on publi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.6.3814-3816.2005
更新日期:2005-06-01 00:00:00
abstract::We previously demonstrated that plasmid-deficient Chlamydia muridarum retains the ability to infect the murine genital tract but does not elicit oviduct pathology because it fails to activate Toll-like receptor 2 (TLR2). We derived a plasmid-cured derivative of the human genital isolate Chlamydia trachomatis D/UW-3/Cx...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01118-10
更新日期:2011-03-01 00:00:00
abstract::Evidence is presented that the chronicity of infection in CBA mice after injection of Brucella abortus 19 is related to a number of factors: (i) the relative resistance of B. abortus to macrophage killing, which allowed some bacteria to survive the peak of macrophage activity occurring at 14 days; (ii) the decline in ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.23.2.197-205.1979
更新日期:1979-02-01 00:00:00
abstract::The pneumocandins are potent antifungal agents of the echinocandin class which are under development for use as broad-spectrum antimycotic therapy. One important consideration for any new therapeutic class for treating serious fungal infections is the potential for drug resistance development. In this study we have is...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.64.8.3244-3251.1996
更新日期:1996-08-01 00:00:00
abstract::Studies conducted with F1 and F2 progeny of crosses between strains of inbred mice that differ greatly in their capacity to make an antibody response to type III pneumococcal polysaccharide, dextran B-1355, and lipopolysaccharide from Escherichia coli 0113 have shown that multiple genes influence the magnitude of the ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.45.1.56-61.1984
更新日期:1984-07-01 00:00:00
abstract::Shiga toxin-producing Escherichia coli (STEC) is a food-borne pathogen with a low infectious dose that colonizes the colon in humans and can cause severe clinical manifestations such as hemolytic-uremic syndrome. The urease enzyme, encoded in the STEC chromosome, has been demonstrated to act as a virulence factor in o...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00210-12
更新日期:2012-08-01 00:00:00