Abstract:
:In this study, native cells of Streptococcus mutans VA-29R and Streptococcus rattus FA-1 displayed significantly higher aminopeptidase activity than did cells of Streptococcus cricetus AHT or Streptococcus sobrinus 6715 toward the nitroanilide derivatives of leucine, alanine, methionine, arginine, and lysine. These differences in cellular aminopeptidase activity led us to investigate the subcellular localization of the aminopeptidase in these mutans group streptococci. Following conversion of native cells to protoplasts by treatment with lysozyme, most of the aminopeptidase activity detected in the native-cell preparations remained associated with the intact protoplasts. After lysis of protoplasts and differential centrifugation, most of the total cellular aminopeptidase activity was recovered with the cytoplasmic fraction. Membrane-associated aminopeptidases represented only minor activities in these mutans group streptococci. Although the four strains showed no differences with respect to a predominant cytoplasmic localization for the aminopeptidase activities, the levels of activity in the cytoplasmic fractions from S. cricetus AHT and S. sobrinus 6715 were significantly lower than those measurable in the corresponding fractions from S. mutans VA-29R and S. rattus FA-1. These results support the conclusion that the differences in aminopeptidase activity expressed by these streptococci reflect quantitative differences rather than differences in enzyme subcellular localization.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Cowman RA,Baron SSdoi
10.1128/IAI.61.1.182-186.1993subject
Has Abstractpub_date
1993-01-01 00:00:00pages
182-6issue
1eissn
0019-9567issn
1098-5522journal_volume
61pub_type
杂志文章abstract::Neisseria lactamica, a common human pharyngeal commensal, contributes to acquired immunity to Neisseria meningitidis. To define the surface antigens shared between these two species, we used monoclonal antibodies (MAbs) to study 35 N. lactamica strains isolated in various parts of the world for cross-reactivity with m...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.2.602-608.1989
更新日期:1989-02-01 00:00:00
abstract::Borrelia burgdorferi undergoes differential gene expression during transmission from its tick vector to a vertebrate host. The addition of blood to a spirochete culture at 35 degrees C for 48 h had a dramatic effect on gene expression of this organism. Utilizing B. burgdorferi whole genome DNA arrays, we compared the ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.9.5419-5432.2004
更新日期:2004-09-01 00:00:00
abstract::Cell-free hemoglobin (Hb) is being developed as an erythrocyte substitute. We have previously demonstrated that cell-free Hb is an endotoxin-binding protein which disaggregates endotoxin and subsequently increases the biological activity of endotoxin in several in vitro assays. Because much of the morbidity and mortal...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.4.1258-1266.1997
更新日期:1997-04-01 00:00:00
abstract::The intravascular trematode Schistosoma mansoni is a causative agent of schistosomiasis, a disease that constitutes a major health problem globally. In this study we cloned and characterized the schistosome tegumental phosphodiesterase SmNPP-5 and evaluated its role in parasite virulence. SmNPP-5 is a 52.5-kDa protein...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05431-11
更新日期:2011-10-01 00:00:00
abstract::We have investigated the ability of two species of streptococci isolated from the human oral cavity (Streptococcus mutans NCTC 10449 and Streptococcus sobrinus SL-1) to metabolize N-acetylglucosamine (GlcNAc), a naturally occurring amino sugar present in saliva and human glycoproteins, when provided as the sole fermen...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.1.295-302.1993
更新日期:1993-01-01 00:00:00
abstract::In studies of experimental Lyme disease, a major obstacle has been the unavailability of a suitable animal model. We found that irradiated LSH/Ss Lak hamsters developed arthritis after injection of Borrelia burgdorferi in the hind paws. When nonirradiated hamsters were injected in the hind paws with B. burgdorferi, ac...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.9.2336-2342.1988
更新日期:1988-09-01 00:00:00
abstract::The humoral and cell-mediated immune responses of murine lymphocytes exposed to lead in vivo and in vitro were investigated. In vivo Pb was administered via the drinking water (0 to 10 mM) for 1 to 10 weeks. In vivo exposure of the mice to Pb did not alter significantly their plaque-forming cell response to sheep eryt...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.31.1.136-143.1981
更新日期:1981-01-01 00:00:00
abstract::The localization and population levels of the indigenous bacterial flora of conventional rats were investigated by cultural and histological techniques. Lactobacilli predominate in the stomach and upper part of the small intestine and associate with keratinized cells of the nonglandular portion of stomach. Mixtures of...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.11.5.962-968.1975
更新日期:1975-05-01 00:00:00
abstract::Chronic granulomatous disease (CGD) is a genetic disorder of NADPH oxidase in which phagocytes are defective in generating reactive oxidants. CGD patients suffer from recurrent infections and exuberant and persistent tissue granuloma formation. We hypothesized that abnormal granulomata in CGD may result from aberrant ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1999-04-01 00:00:00
abstract::The human pathogen enterohemorrhagic Escherichia coli (EHEC) O157:H7 has two histidine sensor kinases, QseC and QseE, which respond to the mammalian adrenergic hormones epinephrine and norepinephrine by increasing their autophosphorylation. Although QseC and QseE are present in nonpathogenic strains of E. coli, EHEC e...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.05921-11
更新日期:2012-02-01 00:00:00
abstract::Tuberculous pleurisy allows the study of human cells at the site of active Mycobacterium tuberculosis infection. In this study, we found that among pleural fluid (PF) lymphocytes, natural killer (NK) cells are a major source of early gamma interferon (IFN-gamma) upon M. tuberculosis stimulation, leading us to investig...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00381-07
更新日期:2007-11-01 00:00:00
abstract::We produced anti-idiotype antibodies to antibody to lipid A from Eikenella corrodens. The ALA-1 monoclonal antibody (immunoglobulin M [IgM] isotype), which had already been produced in our laboratory (T. Kato, I. Takazoe, and K. Okuda, Infect. Immun. 57:656-659, 1989), had reacted strongly with lipid A from E. corrode...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.2.416-420.1990
更新日期:1990-02-01 00:00:00
abstract::A gene encoding a heat-stable enterotoxin (ST) from an Escherichia coli strain isolated from a human with diarrhea was cloned and characterized by nucleotide sequence analysis. The gene was found to be partially homologous to a previously characterized ST gene from an E. coli strain of bovine origin. Hybridization stu...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.3.1167-1174.1983
更新日期:1983-03-01 00:00:00
abstract::Kinetoplastid membrane protein 11 (KMP-11) from Leishmania donovani is an abundant 11-kDa surface membrane glycoprotein. Lymph node cells from mice of six different H-2 haplotypes immunized with KMP-11 or with L. donovani promastigotes were stimulated to proliferate in vitro KMP-11. Primed purified T cells required an...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.11.4893-4899.1994
更新日期:1994-11-01 00:00:00
abstract::Evidence showing that neutrophils play a protective role in the host response to infection by different intracellular parasites has been published in the past few years. We assessed this issue with regard to the infection of mice with Mycobacterium tuberculosis. We found a chronic recruitment of neutrophils to the inf...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.2.577-583.2000
更新日期:2000-02-01 00:00:00
abstract::Hot phenol-water extraction of smooth Brucella abortus and B. melitensis cells yielded a toxic fraction which was recovered from the phenol phase (fraction 5). Chemically, fractions 5 from both Brucella species were lipid-carbohydrate-protein-2 keto-3-deoxyoctulosonic acid complexes which were stable to heat and resis...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1970-02-01 00:00:00
abstract::Bacterial tyrosine kinases and their cognate protein tyrosine phosphatases are best known for regulating the biosynthesis of polysaccharides. Moreover, their roles in the stress response, DNA metabolism, cell division, and virulence have also been documented. The aim of this study was to investigate the pathogenicity ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02713-14
更新日期:2015-02-01 00:00:00
abstract::Toxic protein(s) neutralized with anti-C2 toxic serum was extracted from Clostridium botulinum type C spores treated with an alkaline mercaptoethanol solution. C2 toxicity in the spores was located in the spore coat fraction and was more heat stable than that found in culture fluid. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.41.2.858-860.1983
更新日期:1983-08-01 00:00:00
abstract::Ehrlichia chaffeensis, an obligatory intracellular bacterium of monocytes or macrophages, is the etiologic agent of human monocytic ehrlichiosis. Our previous study showed that gamma interferon (IFN-gamma) added prior to or at early stage of infection inhibited infection of human monocytes with E. chaffeensis; however...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.6.2514-2520.1998
更新日期:1998-06-01 00:00:00
abstract::In order to ascertain if Cryptococcus neoformans components can induce interleukin-6 (IL-6) production, we stimulated human whole blood with purified capsular products. Their potencies in stimulating IL-6 release were mannoproteins > galactoxylomannan = glucuronoxylomannan > alpha(1-3)glucan. IL-6 production was tumor...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.65.6.2454-2456.1997
更新日期:1997-06-01 00:00:00
abstract::Association of Salmonella typhimurium with MDCK epithelial cells in monolayers, represented primarily by intracellular bacteria after 30 min of contact, with centrifugation followed by vigorous washing, was measured during aerobic and anaerobic growth of the bacteria in brain heart infusion broth. Cell association was...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.4.1462-1467.1995
更新日期:1995-04-01 00:00:00
abstract::A 95-kDa protein was isolated from Staphylococcus saprophyticus 7108 grown on dialysis membranes placed on the surface of brain heart infusion agar. Strain CCM883 did not produce this protein. Ultrathin sections revealed the presence of very thin, tuftlike, 50- to 75-nm-long structures on the surface of strain 7108, w...
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
abstract::Pseudomonas aeruginosa bacteremia in cancer patients develops from initial gastrointestinal (GI) colonization with translocation into the bloodstream in the setting of chemotherapy-induced neutropenia and GI mucosal damage. We established a reproducible mouse model of P. aeruginosa GI colonization and systemic spread ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.4.2262-2272.2005
更新日期:2005-04-01 00:00:00
abstract::We studied the antigenicity of a wild-type flagellate and motile (F+M+) Campylobacter jejuni strain (81116) and two daughter mutants, one flagellate and immotile (F+M-) and one aflagellate and immotile (F-M-). By sodium dodecyl sulfate-polyacrylamide gel electrophoresis of acid-extracted surface proteins, a 63-kilodal...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1986-07-01 00:00:00
abstract::Coxiella burnetii, phase I and II, cells cultivated in the yolk sac of chicken embryos were separated from host cell components by two cycles of isopycnic Renografin gradient centrifugation. Initial steps in the purification of viable C. burnetii involved differential centrifugation and sedimentation through an aqueou...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.32.2.840-851.1981
更新日期:1981-05-01 00:00:00
abstract::The antihistoplasma activity of recombinant murine gamma interferon (rMuIFN-gamma)-treated macrophages of the RAW 264.7 cell line depends on the generation of nitric oxide (NO.) from L-arginine. Macrophages of the P388D1 cell line treated with rMuIFN-gamma do not produce NO. or inhibit the intracellular growth of Hist...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.4.1478-1479.1994
更新日期:1994-04-01 00:00:00
abstract::The adenylate cyclase-hemolysin of Bordetella pertussis consists of a cell-invasive N-terminal adenylate cyclase domain linked to a C-terminal RTX hemolysin containing extensive glycine-rich repeats. The toxin is an essential virulence factor required in the initial stages of infection. Adenylate cyclase-hemolysin was...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.63.9.3309-3315.1995
更新日期:1995-09-01 00:00:00
abstract::The adsorption of (3)H-labeled Streptococcus mutans 6715 cells to disks of hydroxyapatite (HA) was studied. The number of streptococci that adsorbed was logarithmically related to the concentration of cells available up to at least 2 x 10(8) per ml; equilibrium occurred within 45 min. Assay reliability was verified by...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.18.2.514-523.1977
更新日期:1977-11-01 00:00:00
abstract::BCG vaccines are a family of closely related daughter strains of an attenuated isolate of Mycobacterium bovis derived by in vitro passage from 1908 to 1921. During subsequent laboratory propagation of the vaccine strain until its lyophilization in 1961, BCG Pasteur underwent at least seven further genomic mutations. T...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.5.2803-2809.2004
更新日期:2004-05-01 00:00:00
abstract::An antigenic complex has been isolated in a highly purified from from the Melvin strain of Neisseria gonorrhoeae. The complex has a molecular weight of 9.3 x 10(6) and on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was found to consist of several subunits; the most predominant had the following molecular...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.25.2.635-644.1979
更新日期:1979-08-01 00:00:00