Date of Award

5-1-2003

Degree Type

Restricted Access Thesis

Degree Name

Master of Science

Field of Study

Microbiology and Immunology

Department

Graduate School of Biomedical Sciences

First Advisor

Mart Hart

Second Advisor

Jerry Simecka

Third Advisor

Ming-Chi Wu

Abstract

Pulse, Mark E., Effects of Serine protease-like F (Sp1F) on Alpha-Toxin Expression in Staphylococcus aureus. Master’s of Science (Microbiology). May 2003. Pages-67. Table-5. Figures-9. Transposon mutagenesis (Tn551) was used to generate agr-suppressor mutations in the agr-null Staphylococcus aureus strain RN6911 (Δagr;;tmn). Firty-four suppressor mutants displaying changes in hemolysin, protease, and lipase activities were isolated, and only twenty-six mutants contained Tn551 within their chromosomes. Transposon insertion sites for seven mutants were determined by sequencing amplicons generated by arbitrary-PCR. One of the insertion sites was within the serine protease-like F (spʅF) gene. Alpha-toxin message levels for the spʅF mutant were similar to RN6911. However, alpha-toxin activity in spent media isolated from the spʅF mutant were similar to RN6911. However, alpha-toxin activity in spent media isolated from the spʅF mutant was increased ten-fold as compared to RN6911. Transduction of the spʅf:Tn551 mutation back into the parental strain verified the link between the phenotype and the mutation. Whole cell lysates from Escherichia coli cells containing a plasmid copy of spʅF displayed protease activity on casein. These data suggest that SpʅF may be post-translationally modifying alpha-toxin through proteolysis.

Comments

Pulse, Mark E., Effects of Serine protease-like F (Sp1F) on Alpha-Toxin Expression in Staphylococcus aureus. Master’s of Science (Microbiology). May 2003. Pages-67. Table-5. Figures-9. W 4.5 P982E 2003

Share

COinS