Detection and identification of group B streptococci by use of pigment production.

Noble, Michael A.; Bent, J M; West, Aileen A.

doi:10.1136/jcp.36.3.350

Cited by 22 publications

(19 citation statements)

References 6 publications

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“…Fallon (1974) proposed the use of pigment detection as a diagnostic tool for GBS identification. This orange, brick or red pigment is unique and highly specific for GBS isolates and is used in the clinical laboratory for the identification of GBS (Fallon, 1974; Merrit & Jacobs, 1976; Merrit et al ., 1976; Noble et al ., 1983; Rosa-Fraile et al ., 1999b; Spellerberg & Brandt, 2011). Nevertheless, pigment production can be variable among bovine strains and other animal species isolates (Mhalu, 1976; Merritt & Jacobs, 1978; Brglez, 1983; Lämmler et al ., 1985; Garcia et al ., 2008).…”

Section: Gbs Pigmentmentioning

confidence: 99%

Group B streptococcal haemolysin and pigment, a tale of twins

Rosa-Fraile¹,

Dramsi²,

Spellerberg³

2014

FEMS Microbiol Rev

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Group B streptococcus [(GBS or Streptococcus agalactiae)] is a leading cause of neonatal meningitis and septicaemia. Most clinical isolates express simultaneously a β-haemolysin/cytolysin and a red polyenic pigment, two phenotypic traits important for GBS identification in medical microbiology. The genetic determinants encoding the GBS haemolysin and pigment have been elucidated and the molecular structure of the pigment has been determined. The cyl operon involved in haemolysin and pigment production is regulated by the major two-component system CovS/R, which coordinates the expression of multiple virulence factors of GBS. Genetic analyses indicated strongly that the haemolysin activity was due to a cytolytic toxin encoded by cylE. However, the biochemical nature of the GBS haemolysin has remained elusive for almost a century because of its instability during purification procedures. Recently, it has been suggested that the haemolytic and cytolytic activity of GBS is due to the ornithine rhamnopolyenic pigment and not to the CylE protein. Here we review and summarize our current knowledge of the genetics, regulation and biochemistry of these twin GBS phenotypic traits, including their functions as GBS virulence factors.

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Section: Gbs Pigmentmentioning

confidence: 99%

Group B streptococcal haemolysin and pigment, a tale of twins

Rosa-Fraile¹,

Dramsi²,

Spellerberg³

2014

FEMS Microbiol Rev

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“…The medium is also cumbersome to use from the standpoint of requiring anaerobic culture conditions. Approximately 3 to 4% of group B streptococcus isolates fail to produce the caratinoid pigment even under optimal growth conditions (9,13,14). The occasional failures seen in the LIM broth enhanced detection methods may be due to the inhibition of the group B streptococcal growth in the LIM broth when Enterococcus sp.…”

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confidence: 99%

Evaluation of Methods To Increase the Sensitivity and Timeliness of Detection of Streptococcus agalactiae in Pregnant Women

et al. 2002

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Streptococcus agalactiae (group B streptococcus) is a significant cause of perinatal and neonatal infections in the United States. Colonization occurs in 10 to 30% of pregnant women (1, 7, 10) and is responsible for 1.8 neonatal infections per 1,000 live births per year (8). Neonatal colonization with group B streptococcus occurs in about 11% of babies (2). Screening of pregnant women for group B streptococcus is aimed at identifying those pregnancies at highest risk for developing maternal and neonatal diseases. The Centers for Disease Control and Prevention presently recommends culturing samples from pregnant women at 35 to 37 weeks gestation for S. agalactiae from vaginal and anorectal swabs after 18 to 24 h of growth in a selective enrichment medium, such as LIM or SBM (8). This process requires a minimum of 48 h to complete. A more rapid and sensitive method would be beneficial, especially in dealing with patients who present for delivery without any prenatal care. Although rapid detection techniques are available, none of these methods have the sensitivity needed to identify colonized women (5). Similarly, direct culture onto solid medium, such as sheep blood agar plates (SBAP), underestimates the actual incidence of rectovaginal colonization (3,4,15). Recently, new techniques have become available that may increase the sensitivity of group B streptococcus detection or decrease the turnaround time until detection. Granada agar is a differential medium that was developed to identify colonies of group B streptococci by their orange pigment production (9) while the AccuProbe S. agalactiae rRNA probe assay (GenProbe, San Diego, Calif.) was developed to detect bacterial rRNA. This study investigated the use of both Granada agar and the AccuProbe assay as potential methods for increasing the detection of S. agalactiae in pregnant women and in decreasing the turnaround time for reporting the results.Four hundred sixty-three serially collected anovaginal swab specimens were tested in parallel by three different group B streptococcus detection methods. Swabs were inoculated directly onto Granada agar (Hardy Diagnostics, Santa Maria, Calif.) and were then placed into LIM broth (Remel, Lenexa, Kans.). Granada agar was incubated anaerobically at 35°C and was examined after 24 and 48 h of incubation. S. agalactiae colonies were detected by their production of an orange pigment. Such colonies were confirmed as S. agalactiae by using the Streptex latex agglutination reagent (Murex Biotech Ltd., Dartford, England). LIM broth was incubated aerobically at 35°C for 18 to 24 h. The broth was then subcultured onto an SBAP (Remel) for detection of beta-hemolytic colonies after 24 h of additional growth on the solid medium. Beta-hemolytic colonies were again confirmed as S. agalactiae by using the Streptex latex agglutination reagent. Immediately after inoculating the SBAP, the LIM broth was thoroughly mixed by using a vortex-type mixer and a 50-l aliquot that was tested by using the AccuProbe S. agalactiae rRNA probe assay (Gen...

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“…The ability to produce pigment appears to be related to the ability to release a haemolysin in that non-haemolytic strains usually lack pigment (Noble et al, 1983) and the simultaneous loss of both properties has been recorded either as a spontaneous event (Lancefield, 1934) or after exposure to mutagens (Wennerstrom et al, 1985). Similarities have also been observed in the formation of these two products in vitro.…”

Section: Introductionmentioning

confidence: 99%

Relationship between pigment production and haemolysin formation by Lancefield group B streptococci

Tapsall

1987

Journal of Medical Microbiology

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Summary. Group B streptococci produce both a pigment and a haemolysin. The requirements of group B streptococci for the formation and release of pigment and haemolysin are similar and have been examined to extend observations on the relationship between the two products. The amount of pigment and haemolysin extractable from actively metabolising washed-cell suspensions of group B streptococci varied with the atmosphere of incubation, the pH at which the extraction was carried out and the presence of Mg2+ ions. Both pigment and haemolysin were produced in significant amounts in all phases of the growth cycle. When conditions were established for obtaining maximum yields of haemolysin, its production correlated closely with pigment yields, but pigment did not function as a carrier for haemolysin. Formation of pigment, but not of haemolysin, increased in the presence of trimethoprim or higher concentrations of glucose. The composition of pigment produced in different conditions differed qualitatively and different strains of group B streptococci formed pigment of different appearance, suggesting that group B streptococcal pigment is composed of several different substances.

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Detection and identification of group B streptococci by use of pigment production.

Cited by 22 publications

References 6 publications

Group B streptococcal haemolysin and pigment, a tale of twins

Group B streptococcal haemolysin and pigment, a tale of twins

Evaluation of Methods To Increase the Sensitivity and Timeliness of Detection of Streptococcus agalactiae in Pregnant Women

Relationship between pigment production and haemolysin formation by Lancefield group B streptococci

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