Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-8-16
pubmed:abstractText
The ability of Streptococcus pyogenes to enter a quiescent state, similar to the stationary phase of lab cultures, is believed to be an important factor in its ability to persist within the host and to subsequently cause disease. Using a model broth system, we determined that after entering the stationary phase, there was a 99.99% reduction in cell viability over a 4-day period, following which the cells appeared to enter a resistant starvation state where cell numbers remained constant over the subsequent 3-4 weeks. This starvation response was induced by carbon or phosphorous limitation, but not by nitrogen limitation in the form of amino acids where cells became non-culturable after 4 days. Amino acid utilization in the absence of a carbon source may be an essential factor for the long-term survival of this bacterium in the stationary phase. Early stationary phase cells showed a greater resistance to oxidative and pH stress compared to 24-h-starved cultures. There was evidence for the formation of a viable but non-culturable state as indicated by a comparison of the numbers of cells with a functional membrane potential (rhodamine 123) against culturable cells on either Todd Hewitt broth agar or sheep blood agar. Long-term survival of S. pyogenes was dependent on both cell wall and protein synthesis, suggesting that starving cultures are a dynamic cell population.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0378-1097
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
176
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
421-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Survival of Streptococcus pyogenes under stress and starvation.
pubmed:affiliation
Department of Microbiology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't