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Updated: Aug 7, 2026
10:39
Methodology for the Study of Horizontal Gene Transfer in Staphylococcus aureus
Published on: March 10, 2017
Natural transformation of Streptococcus crista
F F Correia1, T L McKay, M F Farrow
1Department of Microbiology, School of Dental Medicine, University of Pennsylvania, Philadelphia 19104-6002, USA.
FEMS Microbiology Letters
|September 15, 1996
Summary
Streptococcus crista can be genetically transformed, offering new research possibilities for oral streptococci. This finding expands genetic manipulation capabilities beyond the commonly used Streptococcus gordonii Challis strain.
Area of Science:
- Oral microbiology
- Bacterial genetics
- Streptococcal research
Background:
- Streptococcus gordonii Challis is a standard for genetic manipulation in oral streptococci due to its high natural competence.
- However, S. gordonii Challis is not ideal for studying oral microbial adherence.
- The sanguis group of oral streptococci has been reorganized, necessitating new model strains.
Purpose of the Study:
- To investigate the transformability of other members of the sanguis group, specifically Streptococcus crista.
- To determine if S. crista can be genetically manipulated using both plasmid and chromosomal DNA.
- To provide alternative strains for genetic studies of oral streptococci, particularly for adherence-related properties.
Main Methods:
- Culturing of Streptococcus crista strains.
- Transformation experiments using plasmid and chromosomal DNA.
- Optimization of transformation timing based on growth curve analysis.
Main Results:
- Streptococcus crista strains demonstrate reasonable transformation frequencies.
- Successful transformation was achieved with both plasmid and chromosomal DNA.
- Transformation efficiency is dependent on the timing during the bacterial growth curve.
Conclusions:
- Streptococcus crista is a viable alternative for genetic manipulation within the sanguis group of oral streptococci.
- The ability to transform S. crista facilitates genetic studies of properties specific to these strains.
- This research expands the toolkit for investigating oral microbial communities and their functions.
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