Usage Information
Abstract
Group A streptococci were grown in the presence of [2-3H]glycerol. Concentrated suspensions of the labeled organisms were incubated with and without penicillin. [3H]Glycerol-labeled material accumulated in the supernates in increasing amounts with increasing concentrations of penicillin, ranging from 0 to 50 U/ml. The excretion of labeled material occurred in the absence of nucleic acid synthesis or bacteriolysis indicating that the phenomenon is independent of cell multiplication or decay. The accumulation of label was paralleled by an accumulation of erythrocyte-sensitizing material measured by passive hemagglutination tests for lipoteichoic acid antigen, indicating that a portion of the labeled material possessed the properties of lipoteichoic acid. Culture supernates were fractionated by column chromatography, and the materials obtained were analyzed by electrophoresis on sodium dodecyl sulfate polyacrylamide, thin-layer chromatography, and paper chromatography. The ability of the same materials to bind to human erythrocytes and epithelial cells was tested. The culture supernate contained lipoteichoic acid, deacylated lipoteichoic acid, glycerol phosphate, and free glycerol. Penicillin caused an increase in the amounts of each of the excreted materials. Streptococci that were stimulated with penicillin to lose their lipoteichoic acid (previously shown to mediate adherence of group A streptococci) lost their ability to adhere to buccal mucosal cells, suggesting that penicillin may influence bacterial ecology by mechanisms other than killing sensitive organisms.
Authors
Michael L. Alkan, Edwin H. Beachey
Usage data is cumulative from November 2024 through November 2025.
| Usage | JCI | PMC |
|---|---|---|
| Text version | 192 | 7 |
| 51 | 6 | |
| Scanned page | 202 | 0 |
| Citation downloads | 84 | 0 |
| Totals | 529 | 13 |
| Total Views | 542 | |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)