Abstract:
:Neisseria gonorrhoeae releases peptidoglycan fragments during growth, and these molecules induce an inflammatory response in the human host. The proinflammatory molecules include peptidoglycan monomers, peptidoglycan dimers, and free peptides. These molecules can be released by the actions of lytic transglycosylases or an amidase. However, >40% of the gonococcal cell wall is cross-linked, where the peptide stem on one peptidoglycan strand is linked to the peptide stem on a neighboring strand, suggesting that endopeptidases may be required for the release of many peptidoglycan fragments. Therefore, we characterized mutants with individual or combined mutations in genes for the low-molecular-mass penicillin-binding proteins PBP3 and PBP4. Mutations in either dacB, encoding PBP3, or pbpG, encoding PBP4, did not significantly reduce the release of peptidoglycan monomers or free peptides. A mutation in dacB caused the appearance of a larger-sized peptidoglycan monomer, the pentapeptide monomer, and an increased release of peptidoglycan dimers, suggesting the involvement of this enzyme in both the removal of C-terminal d-Ala residues from stem peptides and the cleavage of cross-linked peptidoglycan. Mutation of both dacB and pbpG eliminated the release of tripeptide-containing peptidoglycan fragments concomitantly with the appearance of pentapeptide and dipeptide peptidoglycan fragments and higher-molecular-weight peptidoglycan dimers. In accord with the loss of tripeptide peptidoglycan fragments, the level of human NOD1 activation by the dacB pbpG mutants was significantly lower than that by the wild type. We conclude that PBP3 and PBP4 overlap in function for cross-link cleavage and that these endopeptidases act in the normal release of peptidoglycan fragments during growth.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Schaub RE,Perez-Medina KM,Hackett KT,Garcia DL,Dillard JPdoi
10.1128/IAI.00833-18subject
Has Abstractpub_date
2019-01-24 00:00:00issue
2eissn
0019-9567issn
1098-5522pii
IAI.00833-18journal_volume
87pub_type
杂志文章abstract::An enterotoxic factor isolated from cultures of Salmonella yielded reproducible results in the suckling mouse model in contrast to other animal models. The enterotoxin appears to possess properties similar to both the heat-stable and heat-labile enterotoxins of Escherichia coli. Preliminary results indicate that the t...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.11.1.14-22.1975
更新日期:1975-01-01 00:00:00
abstract::The naturally antibiotic-resistant bacterium Burkholderia pseudomallei is the causative agent of melioidosis, a disease with stubbornly high mortality and a complex, protracted treatment regimen. The worldwide incidence of melioidosis is likely grossly underreported, though it is known to be highly endemic in northern...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00938-17
更新日期:2018-04-23 00:00:00
abstract::In this work, apolipoprotein A-I (ApoA-I) was purified from pig sera. The responses of this protein after sterile inflammation and in animals infected with Actinobacillus pleuropneumoniae or Streptococcus suis were investigated. Decreases in the concentrations of ApoA-I, two to five times lower than the initial values...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.5.3184-3187.2005
更新日期:2005-05-01 00:00:00
abstract::When type I Candida stellatoidea is plated onto sucrose agar at levels in excess of 10(8) cells, some isolates spontaneously form sucrose-positive colonies. These isolates do not display typical type I phenotypes but instead exhibit phenotypes intermediate between type I C. stellatoidea and C. albicans. Also, this phe...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.5.1762-1771.1991
更新日期:1991-05-01 00:00:00
abstract::Fusobacterium nucleatum is closely associated with human periodontal diseases and may also be a causative agent in other infections, such as pericarditis, septic arthritis, and abscesses of tonsils and liver. Initiation and outcome of infective diseases depend critically on the host cell signaling system altered by th...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.2.1171-1179.2005
更新日期:2005-02-01 00:00:00
abstract::We measured the microbicidal peptides MCP-1 and MCP-2 in rabbit alveolar macrophages (AM), comparing rabbits pretreated with complete Freund adjuvant with untreated control animals. Levels of MCP-1 increased from 4.7 +/- 0.6 microgram/10(7) resident AM to 13.2 +/- 0.1 microgram/10(7) complete Freund adjuvant-elicited ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.33.3.775-778.1981
更新日期:1981-09-01 00:00:00
abstract::Suitability of the rhesus monkey (Macaca mulatta) as an experimental host for evaluation of vaccines against airborne infection with Mycobacterium tuberculosis strain H37Rv was investigated. Nonvaccinated monkeys were exposed to estimated doses of 12, 25, or 49 units of H37Rv in a modified Henderson apparatus, and the...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.2.5.574-582.1970
更新日期:1970-11-01 00:00:00
abstract::In experimentally infected human volunteers, the cutaneous immune response to Haemophilus ducreyi is orchestrated by serum, polymorphonuclear leukocytes, macrophages, T cells, and myeloid dendritic cells (DC). This response either leads to spontaneous resolution of infection or progresses to pustule formation, which i...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00777-07
更新日期:2007-12-01 00:00:00
abstract::We used inhibitors of receptor-mediated endocytosis to study the mechanisms of infectivity, especially the uptake mechanism, of Chlamydia trachomatis for cultured cells. The effect of methylamine and monodansylcadaverine on the different stages of the chlamydial growth cycle in McCoy cells was examined. There was a do...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.40.2.534-541.1983
更新日期:1983-05-01 00:00:00
abstract::Bacteria exhibit extensive genetic heterogeneity within species. In many cases, these differences account for virulence properties unique to specific strains. Several such loci have been discovered in the genome of the type b serotype of Haemophilus influenzae, a human pathogen able to cause meningitis, pneumonia, and...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.3.1098-1108.2003
更新日期:2003-03-01 00:00:00
abstract::Human opsonins directed against specific meningococcal outer membrane structures in sera obtained during meningococcal disease were quantified with a recently developed antigen-specific, opsonin-dependent phagocytosis and oxidative burst assay. Outer membrane vesicles (OMVs) and PorA (class 1) and PorB (class 3) prote...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.5.2552-2560.1999
更新日期:1999-05-01 00:00:00
abstract::The purpose of the present study was to determine the extent of immunologic responses, particularly immunopathologic responses, within the upper and lower respiratory tracts after intranasal immunization using the mucosal adjuvant cholera toxin (CT). BALB/c mice were nasally immunized with influenza virus vaccine comb...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.4.2328-2338.2001
更新日期:2001-04-01 00:00:00
abstract::B cell activating factor of the tumor necrosis factor family (BAFF) is an essential survival factor for B cells and has been shown to regulate T cell-independent (TI) IgM production. During Ehrlichia muris infection, TI IgM secretion in the spleen was BAFF dependent, and antibody-mediated BAFF neutralization led to an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00998-13
更新日期:2013-12-01 00:00:00
abstract::Apical membrane antigen 1 (AMA-1) is an invasion-related Plasmodium antigen that is expressed during both intracellular and extracellular asexual stages of the parasite's life cycle, making it an ideal target for induction of humoral and cellular immune responses that can protect against malaria. We show here that whe...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05048-11
更新日期:2011-09-01 00:00:00
abstract::The cell surface hydrophobicity of 10 pigmented and 4 nonpigmented clinical Serratia marcescens strains was studied, based on the ability of the strains to adhere to hydrocarbons and to polystyrene. The cell surface hydrophobicity depended greatly on growth temperature; all of the strains tested were adherent followin...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.51.3.932-935.1986
更新日期:1986-03-01 00:00:00
abstract::Biofilm formation by the periodontal pathogen Aggregatibacter actinomycetemcomitans is dependent upon autoinducer-2 (AI-2)-mediated quorum sensing. However, the components that link the detection of the AI-2 signal to downstream gene expression have not been determined. One potential regulator is the QseBC two-compone...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01376-09
更新日期:2010-07-01 00:00:00
abstract::Three types of caseinolytic proteases (Pase-A, Pase-B, and Pase-C) were isolated and purified from culture supernatants of Porphyromonas gingivalis 381 by the combined procedures of acetone precipitation, gel filtration, solubilization with octylthioglucoside followed by affinity chromatography on arginine-Sepharose 4...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.9.3060-3068.1991
更新日期:1991-09-01 00:00:00
abstract::Amebic erythrophagocytosis is characteristic of invasive amebiasis, and mutants deficient in erythrocyte ingestion are avirulent. We sought to understand the molecular mechanisms underlying erythrocyte phagocytosis by Entamoeba histolytica. Following adherence to amebae, erythrocytes became round and crenulated, and p...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.6.3422-3430.2005
更新日期:2005-06-01 00:00:00
abstract::Pili have been demonstrated to be the adhesins of Pseudomonas aeruginosa for mouse epidermal cells. The mechanisms of adhesion of P. aeruginosa to mouse epidermal cells was studied by using four mutants derived from a single strain: flagellated and piliated (F+P+), flagellated and nonpiliated (F+P-), nonflagellated an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.8.1774-1778.1987
更新日期:1987-08-01 00:00:00
abstract::Utilization of heme-hemopexin as a source of heme by Haemophilus influenzae type b is dependent on expression by this bacterium of the 100-kDa HxuA protein, which is both present on the bacterial cell surface and released into the culture supernatant (L. D. Cope, R. Yogev, U. Muller-Eberhard, and E. J. Hansen, J. Bact...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1998-09-01 00:00:00
abstract::Oral treponemes are considered to be important in the development and progression of periodontal diseases. We investigated the mechanisms of recognition and activation of human gingival epithelial cells (HGEC) with the oral treponemes Treponema denticola, Treponema vincentii, and Treponema medium and their outer membr...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.2.717-725.2003
更新日期:2003-02-01 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::Listeria monocytogenes colonized the gastrointestinal tract of adult germfree rats (10(10) to 10(11)/g, dry weight) within 24 h after oral exposure. Between 3 and 14 days after monoassociation, L. monocytogenes caused a self-limiting pseudomembranous colitis, bacteremia, and infection of the spleen and liver. Monoasso...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.32.1.323-331.1981
更新日期:1981-04-01 00:00:00
abstract::Exfoliatin caused skin loss in hairless mutant mice only while they lacked hair, but older mice were more resistant to this effect than neonates. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.6.5.877-879.1972
更新日期:1972-11-01 00:00:00
abstract::Germination of Bacillus anthracis Sterne and plasmidless Delta-Sterne endospores was dramatically enhanced in RAW264.7 macrophage-like cells, while germination of nonpathogenic Bacillus endospores was not. Elimination of gerS, a germinant receptor locus, caused a complete loss of cell-enhanced germination, implicating...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.70.10.5870-5872.2002
更新日期:2002-10-01 00:00:00
abstract::Ocular toxoplasmosis is a potentially blinding intraocular inflammation. The intent of this study was to investigate the role of Fas-FasL interaction in a murine model of acquired ocular toxoplasmosis induced by intracameral inoculation of Toxoplasma gondii. Intraocular inflammation, Fas and FasL expression on lymphoc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.2.928-935.1999
更新日期:1999-02-01 00:00:00
abstract::Synthetic Escherichia coli lipid A and synthetic S-[2,3-bis-(palmitoyloxy)propyl]-N-palmitoylpentapeptide (tripalmitoyl pentapeptide [TPP]), representing the mitogenically active principles of bacterial lipopolysaccharide (LPS) and lipoprotein, respectively, were compared for their mitogenic activities on splenocytes ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1382-1384.1988
更新日期:1988-05-01 00:00:00
abstract::We have reported that P388D1 cell line murine macrophages stimulated with lipopolysaccharide (LPS) from Actinobacillus actinomycetemcomitans release interleukin-1 (IL-1) inhibitor. The IL-1 inhibitor was purified from conditioned media of P388D1 cells stimulated with A. actinomycetemcomitans LPS for 72 h to homogeneit...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.2.390-397.1994
更新日期:1994-02-01 00:00:00
abstract::A secreted nuclease, SsnA, was identified in the virulent Streptococcus suis isolate SX332 and subsequently in each of the type strains of capsular serotypes 1 through 9. Screening of 258 porcine clinical isolates from surface (nasal mucosa or palatine tonsil) or internal (joint, brain or other internal organ) locatio...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.2.774-781.2004
更新日期:2004-02-01 00:00:00
abstract::The adhesion of K21a, K26, K36, and K50 capsulated Klebsiella strains to ileocecal (HCT-8) and bladder (T24) epithelial cell lines was significantly lower than that of their corresponding spontaneous noncapsulated variants K21a/3, K26/1, K36/3, and K50/3, respectively. Internalization of the bacteria by both epithelia...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.12.6744-6749.2000
更新日期:2000-12-01 00:00:00