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Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)
Published on: November 4, 2016
Complete amino acid sequence of staphylococcal enterotoxin A
The Journal of Biological Chemistry
|May 25, 1987
Summary
The complete amino acid sequence of staphylococcal enterotoxin A (SEA) was determined. This research provides the primary structure of SEA, revealing its composition and sequence for the first time.
Area of Science:
- Microbiology
- Protein Chemistry
- Immunology
Background:
- Staphylococcal enterotoxins (SEs) are potent exotoxins produced by Staphylococcus aureus.
- Understanding the primary structure of SEs is crucial for elucidating their function and antigenicity.
Purpose of the Study:
- To determine and present the complete amino acid sequence of staphylococcal enterotoxin A (SEA).
- To provide detailed information on the molecular weight and amino acid composition of SEA.
Main Methods:
- Automated sequence analysis of intact SEA.
- Peptide characterization following cyanogen bromide treatment.
- Enzymatic digestion using trypsin and chymotrypsin.
Main Results:
- The complete primary structure of SEA, a 233-residue polypeptide, was elucidated.
- SEA has a molecular weight of 27,078 Daltons.
- Serine was identified as both the amino- and carboxyl-terminal amino acid.
Conclusions:
- The detailed primary structure of staphylococcal enterotoxin A has been established.
- Comparative analysis suggests lower structural homology between SEA and other SEs (SEB, SEC1) compared to the homology between SEB and SEC1.
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