Abstract:
:The oral streptococcal group (mitis phylogenetic group) currently consists of nine recognized species, although the group has been traditionally difficult to classify, with frequent changes in nomenclature over the years. The pneumococcus (Streptococcus pneumoniae), an important human pathogen, is traditionally distinguished from the most closely related oral streptococcal species Streptococcus mitis and Streptococcus oralis on the basis of three differentiating characteristics: optochin susceptibility, bile solubility, and agglutination with antipneumococcal polysaccharide capsule antibodies. However, there are many reports in the literature of pneumococci lacking one or more of these defining characteristics. Sometimes called "atypical" pneumococci, these isolates can be the source of considerable confusion in the clinical laboratory. Little is known to date about the genetic relationships of such organisms with classical S. pneumoniae isolates. Here we describe these relationships based on sequence analysis of housekeeping genes in comparison with previously characterized isolates of S. pneumoniae, S. mitis, and S. oralis. While most pneumococci were found to represent a closely related group these studies identified a subgroup of atypical pneumococcal isolates (bile insoluble and/or "acapsular") distinct from, though most closely related to, the "typical" pneumococcal isolates. However, a large proportion of isolates, found to be atypical on the basis of capsule reaction alone, did group with typical pneumococci, suggesting that they have either lost capsule production or represent as-yet-unrecognized capsular types. In contrast to typical S. pneumoniae, isolates phenotypically identified as S. mitis and S. oralis, which included isolates previously characterized in taxonomic studies, were genetically diverse. While most of the S. oralis isolates did fall into a well-separated group, S. mitis isolates did not cluster into a well-separated group. During the course of these studies we also identified a number of potentially important pathogenic isolates, which were frequently associated with respiratory disease, that phenotypically and genetically are most closely related to S. mitis but which harbor genes encoding the virulence determinants pneumolysin and autolysin classically associated with S. pneumoniae.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Whatmore AM,Efstratiou A,Pickerill AP,Broughton K,Woodard G,Sturgeon D,George R,Dowson CGdoi
10.1128/iai.68.3.1374-1382.2000keywords:
subject
Has Abstractpub_date
2000-03-01 00:00:00pages
1374-82issue
3eissn
0019-9567issn
1098-5522journal_volume
68pub_type
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.06162-11
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.7.2753-2757.1992
更新日期:1992-07-01 00:00:00
abstract::Inoculation of neonatal CD-1 mice by multiple routes with an amyocarditic temperature-sensitive (ts) mutant (ts 1) derived from a myocarditic parent variant of coxsackievirus B3 (CVB3(m)) resulted in approximately half of the neonates surviving to adolescence. Challenge of the ts 1 survivors with CVB3(m) did not induc...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.2.851-864.1983
更新日期:1983-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.7.4040-4048.2000
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.74.4.2015-2021.2006
更新日期:2006-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.5.1600-1608.1994
更新日期:1994-05-01 00:00:00
abstract::Mice infected with various strains of Salmonella enteritidis and S. typhimurium were found to be more sensitive to the cell wall lipopolysaccharide (LPS) extracted from certain strains of Salmonella than noninfected mice. This hypersensitivity was induced by those smooth or rough strains which possessed a polysacchari...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.4.5.519-524.1971
更新日期:1971-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.42.3.1092-1101.1983
更新日期:1983-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.9.3151-3155.1991
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.5.3.400-405.1972
更新日期:1972-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.6.1381-1386.1987
更新日期:1987-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.7.4.597-599.1973
更新日期:1973-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.31.3.845-849.1981
更新日期:1981-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.7.4.556-560.1973
更新日期:1973-04-01 00:00:00
abstract::Cells infected by Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever, display unusual intracellular morphological changes characterized by dilatation of the membranes of the endoplasmic reticulum and outer nuclear envelope. These changes are consistent with those that might be expected to occur...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.12.3110-3115.1988
更新日期:1988-12-01 00:00:00
abstract::One of the hallmarks of Pseudomonas aeruginosa infection in cystic fibrosis (CF) patients is very-high-cell-density (HCD) replication in the lung, allowing this bacterium to induce virulence controlled by the quorum-sensing systems. However, the nutrient sources sustaining HCD replication in this chronic infection are...
journal_title:Infection and immunity
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doi:10.1128/IAI.01807-06
更新日期:2007-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.67.7.3637-3640.1999
更新日期:1999-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.9.2017-2020.1987
更新日期:1987-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.12.5889-5896.1998
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.2.779-784.1983
更新日期:1983-02-01 00:00:00
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journal_title:Infection and immunity
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doi:10.1128/IAI.46.1.98-104.1984
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.1.599-608.2005
更新日期:2005-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.7.1760-1765.1988
更新日期:1988-07-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.15.3.692-697.1977
更新日期:1977-03-01 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:2010-03-01 00:00:00
abstract::Brucella species can cause brucellosis, a zoonotic disease that causes serious livestock economic losses and represents a public health threat. The mechanism of virulence of Brucella spp. is not yet fully understood. Therefore, it is crucial to identify new molecules that serve as virulence factors to better understan...
journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2015-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.12.7322-7325.2004
更新日期:2004-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.7.3093-3097.1993
更新日期:1993-07-01 00:00:00
abstract::F1651 and the pyelonephritis-associated pili (Pap) are two members of the type P family of adhesive factors. They play a key role in establishing disease caused by extraintestinal pathogenic Escherichia coli (ExPEC) strains in animals and humans. Both F1651 and Pap are under the control of an epigenetic and reversible...
journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2015-05-01 00:00:00
abstract::Vibrio cholerae normally inhabits aquatic habitats but can cause a severe diarrheal illness in humans. Its arsenal of virulence factors includes a secreted hemagglutinin (HA) protease. An HA protease-deficient mutant of V. cholerae was isolated and designated E7946 mpc. E7946 mpc was found to contain a point mutation ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.5.2571-2576.2003
更新日期:2003-05-01 00:00:00