Author
E. M. Hale
Bio: E. M. Hale is an academic researcher from University of Wisconsin-Madison. The author has contributed to research in topics: Bacteriocin & Staphylococcus aureus. The author has an hindex of 2, co-authored 2 publications receiving 57 citations.
Papers
More filters
TL;DR: Staphylococcin 462 was not found in significant concentrations in the supernatant fluid of broth cultures, nor was it released into the suspending liquid when the cells were mechanically disrupted, however, extraction of the cells with 7 M urea resulted in the liberation of much of the activity.
Abstract: Staphylococcus aureus 462 is one of three bacteriocin-producing strains selected for study from 200 isolates of staphylococci of animal origin. These bacteriocins are specific in their activity, inhibiting the growth of certain strains of S. aureus and other gram-positive species, but not gram-negative organisms. Staphylococcin 462 was not found in significant concentrations in the supernatant fluid of broth cultures, nor was it released into the suspending liquid when the cells were mechanically disrupted. However, extraction of the cells with 7 M urea resulted in the liberation of much of the activity. The material was purified by gel permeation chromatography by using Sephadex G-200 and by preparative electrophoresis on polyacrylamide gels in the presence of sodium dodecyl sulfate. Chemical analysis showed that the material consisted of roughly 90% protein and 3% lipid. The molecular weight of sodium dodecyl sulfate-dissociated staphylococcin 462 was calculated to be about 9,000.
34 citations
TL;DR: Of the 70 strains of gram-positive bacteria tested for susceptibility to staphylococcin 462, 24 (34%) were susceptible, distributed among 7 genera, and revealed that S. aureus 140 stops synthesizing protein immediately.
Abstract: Staphylococcin 462 is a proteinaceous inhibitor produced by Staphylococcus aureus strain 462. In broth cultures, susceptible S. aureus strain 140 and 19 respond to treatment with the bacteriocin by stopping growth and cell division. Examination of macromolecular synthesis by measuring the incorporation of radioactive precursors revealed that S. aureus 140 stops synthesizing protein immediately. After exposure to staphylococcin 462, the synthesis of deoxyribonucleic acid and ribonucleic acid is quickly inhibited also, but not as completely. Treatment of S. aureus 140 with the inhibitor causes a rapid drop in cellular adenosine 5'-triphosphate level to about 60% of control levels. Of the 70 strains of gram-positive bacteria tested for susceptibility to staphylococcin 462, 24 (34%), distributed among 7 genera, were susceptible.
24 citations
Cited by
More filters
TL;DR: A group of antibacterial proteins produced by gram-positive bacteria have attracted great interest in their potential use as food preservatives and as antibacterial agents to combat certain infections due to gram- positive pathogenic bacteria.
2,819 citations
TL;DR: Current data contradict some historical classifications of cutaneous microbiota and suggest that these organisms may protect the host, defining them not as simple symbiotic microbes but rather as mutualistic.
Abstract: Microbes found on the skin are usually regarded as pathogens, potential pathogens or innocuous symbiotic organisms. Advances in microbiology and immunology are revising our understanding of the molecular mechanisms of microbial virulence and the specific events involved in the host-microbe interaction. Current data contradict some historical classifications of cutaneous microbiota and suggest that these organisms may protect the host, defining them not as simple symbiotic microbes but rather as mutualistic. This review will summarize current information on bacterial skin flora including Staphylococcus, Corynebacterium, Propionibacterium, Streptococcus and Pseudomonas. Specifically, the review will discuss our current understanding of the cutaneous microbiota as well as shifting paradigms in the interpretation of the roles microbes play in skin health and disease.
782 citations
TL;DR: Data suggest that the production of PSMgamma and PSMdelta by S. epidermidis can benefit cutaneous immune defense by selectively inhibiting the survival of skin pathogens while maintaining the normal skin microbiome.
361 citations
224 citations
TL;DR: This review provides an up-to-date look at the current hypotheses of the mechanisms involved in the inhibition of S. aureus by LAB in both the vaginal ecosystem and in fermented food ecosystems and emphasizes that post-genomic approaches can now be envisioned in order to study these diverse and complex interactions at the molecular level.
193 citations