Diversity of CRISPR-Cas type II-A systems in .

is a commensal Streptococcal species that is often associated with invasive bacterial infections. However, little is known about its molecular genetic background. Many Streptococcal species, including , harbor clustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems.

The Role of SilX in Bacteriocin Production of .

produces the novel antimicrobial peptide Angicin, which inhibits Gram positive microorganisms and is classified as a group IId bacteriocin. Production of Angicin is regulated by the quorum sensing system (Streptococcus invasion locus), which is located adjacent to the bacteriocin gene cluster. Within this genetic region a typical CAAX protease is encoded, which was designated SilX.

Angicin, a novel bacteriocin of Streptococcus anginosus.

As a conserved defense mechanism, many bacteria produce antimicrobial peptides, called bacteriocins, which provide a colonization advantage in a multispecies environment. Here the first bacteriocin of Streptococcus anginosus, designated Angicin, is described. S.

Group B streptococcal colonization in elderly women.

Background: In non-pregnant adults, the incidence of invasive Group B Streptococcus (GBS) disease is continuously increasing. Elderly and immunocompromised persons are at increased risk of infection. GBS commonly colonizes the vaginal tract, though data on colonization in the elderly are scarce.

Heterogeneity of Streptococcus anginosus ß-hemolysis in relation to CRISPR/Cas.

Streptococcus anginosus is a commensal of the oral mucosa that can cause severe invasive infections. A considerable proportion of Streptococcus anginosus strains are ß-hemolytic due to the presence of an SLS-like gene cluster. However, the majority of strains do not display ß-hemolysis.

Regulation of the β-hemolysin gene cluster of Streptococcus anginosus by CcpA.

Streptococcus anginosus is increasingly recognized as an opportunistic pathogen. However, our knowledge about virulence determinants in this species is scarce. One exception is the streptolysin-S (SLS) homologue responsible for the β-hemolytic phenotype of the S.

A streptococcal NRAMP homologue is crucial for the survival of Streptococcus agalactiae under low pH conditions.

Streptococcus agalactiae or Group B Streptococcus (GBS) is a commensal bacterium of the human gastrointestinal and urogenital tracts as well as a leading cause of neonatal sepsis, pneumonia and meningitis. Maternal vaginal carriage is the main source for GBS transmission and thus the most important risk factor for neonatal disease. Several studies in eukaryotes identified a group of proteins natural resistance-associated macrophage protein (NRAMP) that function as divalent cation transporters for Fe(2+) and Mn(2+) and confer on macrophages the ability to control replication of bacterial pathogens.

Chromosomally and Extrachromosomally Mediated High-Level Gentamicin Resistance in Streptococcus agalactiae.

Streptococcus agalactiae (group B Streptococcus [GBS]) is a leading cause of sepsis in neonates. The rate of invasive GBS disease in nonpregnant adults also continues to climb. Aminoglycosides alone have little or no effect on GBS, but synergistic killing with penicillin has been shown in vitro.

Streptolysin S of Streptococcus anginosus exhibits broad-range hemolytic activity.

Streptococcus anginosus is a commensal of mucous membranes and an emerging human pathogen. Some strains, including the type strain, display a prominent β-hemolytic phenotype. A gene cluster (sag), encoding a variant of streptolysin S (SLS) has recently been identified as the genetic background for β-hemolysin production in S.

The β-hemolysin and intracellular survival of Streptococcus agalactiae in human macrophages.

S. agalactiae (group B streptococci, GBS) is a major microbial pathogen in human neonates and causes invasive infections in pregnant women and immunocompromised individuals. The S.

High-level fluorescence labeling of gram-positive pathogens.

Fluorescence labeling of bacterial pathogens has a broad range of interesting applications including the observation of living bacteria within host cells. We constructed a novel vector based on the E. coli streptococcal shuttle plasmid pAT28 that can propagate in numerous bacterial species from different genera.

Human serum induces streptococcal c5a peptidase expression.

Streptococcus agalactiae is a major pathogen in humans and animals. Virulence factors are often associated with mobile genetic elements, and their expression can be modulated by host factors. S.

Rapid identification of beta-hemolytic streptococci by fluorescence in situ hybridization (FISH).

Rapid identification of pathogenic, beta-hemolytic streptococci is important for treatment decisions. We evaluated fluorescence in situ hybridization (FISH) for this purpose using 23 reference strains, 157 clinical isolates, and 80 blood cultures showing streptococci in the Gram stain. With a sensitivity and specificity in excess of 99%, FISH proved to be suitable for rapid identification of beta-hemolytic streptococci in a diagnostic laboratory.

Heterogeneity of hemolysin expression during neonatal Streptococcus agalactiae sepsis.

The beta-hemolysin of Streptococcus agalactiae is a major virulence factor; consequently, nonhemolytic strains rarely cause infections. We report on a case of neonatal sepsis caused by a strain displaying heterogeneous hemolysin expression. It was detected by the simultaneous isolation of hemolytic and nonhemolytic colonies from cultures of the infant's blood.