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Constructing Mutants in Serotype 1 Streptococcus pneumoniae strain 519/43
Published on: September 11, 2020
[Chemical modification of Streptococcus suis type 2 haemolysin]
1Key Lab Animal Disease Diagnostic & Immunology, Ministry of Agricultural, Nanjing Agricultural University, Nanjing 210095, China.
Wei Sheng Wu Xue Bao = Acta Microbiologica Sinica
|November 11, 2005
Summary
Streptococcus suis type 2 haemolysin activity is not dependent on sulfhydryl or amino groups. Tryptophan, histidine, and arginine residues are essential for its function.
Area of Science:
- Microbiology
- Biochemistry
Context:
- Streptococcus suis type 2 is an important pathogen.
- Haemolysins are key virulence factors in bacterial infections.
Purpose:
- To investigate the role of specific amino acid residues and chemical groups in the activity of Streptococcus suis type 2 haemolysin.
Summary:
- Purified Streptococcus suis type 2 haemolysin was subjected to modification using various reagents.
- The haemolysin activity was unaffected by modifications targeting sulfhydryl, amino, carboxyl, and tyrosine groups.
- Significant reduction in haemolysin activity was observed after modification of tryptophan, histidine, and arginine residues, as well as disulfide bonds, suggesting their essentiality.
Impact:
- This research provides crucial insights into the molecular mechanisms of Streptococcus suis virulence.
- Understanding the structure-function relationship of this haemolysin can aid in the development of targeted therapeutics.
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