ArticleInfection and immunity1998
Production of stabilized virulence factor-negative variants by group A streptococci during stationary phase.
Article in Infection and immunity, 1998. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers.
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Who cites it
13 citing papers in PubMed, 43 citations in OpenAlex.
- Hyaluronic acid production by Klebsiella pneumoniae strain H15 (OP354286) under different fermentation conditions.BMC microbiology · 2023Article
- The prince and the pauper: which one is real? The problem of secondary mutation during mutagenesis in Streptococcus pyogenes.Virulence · 2013Article
- The sagA/pel locus does not regulate the expression of the M protein of the M1T1 lineage of group A Streptococcus.Virulence · 2013Article
- Long-term survival of Streptococcus pyogenes in rich media is pH-dependent.Microbiology (Reading, England) · 2012Article
- Variation among genome sequences of H37Rv strains of Mycobacterium tuberculosis from multiple laboratories.Journal of bacteriology · 2010Article
- Generation of metabolically diverse strains of Streptococcus pyogenes during survival in stationary phase.Journal of bacteriology · 2009Article
- Population biology of the human restricted pathogen, Streptococcus pyogenes.Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases · 2009Review
- Persistence of Streptococcus pyogenes in stationary-phase cultures.Journal of bacteriology · 2005Article
- Molecular analysis of the Enterococcus faecalis serotype 2 polysaccharide determinant.Journal of bacteriology · 2003Article
- Role of CsrR, hyaluronic acid, and SpeB in the internalization of Streptococcus pyogenes M type 3 strain by epithelial cells.Infection and immunity · 2002Article
- Role of group A streptococcal virulence factors in adherence to keratinocytes.Infection and immunity · 2000Article
- Absence of SpeB production in virulent large capsular forms of group A streptococcal strain 64.Infection and immunity · 2000Article
- Identification of pel, a Streptococcus pyogenes locus that affects both surface and secreted proteins.Journal of bacteriology · 1999Article
Corrections and comments
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Authors and funding
3 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Many of the virulence factors associated with fulminant group A streptococci (GAS) infection are expressed under in vitro exponential growth conditions. However, the survival of GAS in tissue and intracellularly, as well as colonization of asymptomatic carriers, has been reported for GAS. The bacteria associated with these niches may encounter high-density, low-nutrient-flowthrough conditions that may more closely mimic in vitro stationary-phase conditions than exponential growth. Therefore, the behavior of GAS in stationary-phase culture was examined. We observed that after 24 h in stationary phase, GAS serotypes M49 and M2 developed a unstable colony dimorphism of typical large and atypical small colonies. Between days 4 and 5, we isolated stabilized atypical small colonies which remained stable for up to nine passages (approximately 200 generations) on fresh medium before fully reverting to the large-colony phenotype. Upon analysis, the small colonies showed no difference in cell number per colony, growth rate, survival in prolonged stationary-phase culture, or antibiotic sensitivity. However, the small colonies showed decreased transcription of hyaluronic acid capsule, the global positive virulence factor regulator gene mga, the mga-regulated emm mRNA (M-protein structural gene), and speB (cysteine protease). Accordingly, the small colonies were completely sensitive in a traditional phagocytosis assay. The production of virulence factors and phagocytosis resistance of the small-colony isolates was recovered when, after several passages on fresh medium, the colony morphology began to revert.
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