The first involves the determination and annotation of the sequence ofthe genome of Staphylococcus aureus strain 8325. The mass sequencing phase (carried out in collaboration with Dr. Bruce Roe at the Univ. of Oklahoma-Norman campus) is underway and we will soon begin the annotation and genome map construction. The present physical map and genetic map of the genome is shown here, and serves as the underpinning for eventual presentation of the entire sequence of genome. We are also building a bacterial artificial chromosome (BAC) and bacteriophage lambda library of the major SmaI CHEF gel fragments to be used for annotation,proof reading and gap closure. These constructs will also be used as frameworks upon which to assemble the sequence of the individual fragments. The genome sequence database can be accessed at http://www.genome.ou.edu

We maintain a culture collection cataloged as The Staphylococcal Genetic Stock Center which consists of my collection and the collection of P. A. Pattee and contains more than 5,000 marked and cataloged trains. Ultimately the BAC and lambda clones will be added to the culture collections we administer. Requests for cultures should be sent to me at this address.

The second project involves molecular characterization and sequencing of the staphylococcal plasmid pRW001 which encodes the genes for exfoliative toxin B and for the broad spectrum bacteriocin BacR1. BacR1 is a powerful anti-staphylococcal substance that is highly hydrophobic and is being developed as a new class of antibiotic. Intensive efforts are underway to identify, map and characterize the bacteriocin genes. Because of its broad spectrum of activity, it has great potential for use in antibiotic therapy of a number of wide-spread infections of man and animals. The BacR1 genes are located on a 10 kb complex operon encoding the structural gene, genes for modification ,transport and immunity. The material is extracellular, has a molecular weight of 3218 daltons is membrane active and bacteriocidal but does not lyse cells. BacR1 has low-level antigenicity, is active against gram positive bacteria, gram negative bacteria and some animal cell lines and appears to be non-toxic in animal challenge studies.

Exfoliative toxin B (Etb) is also encoded on pRW001. Although genetically and pathophysiologically very similar to its counterpart exfoliative toxin A (Eta), each resides in different genetic loci. Eta is a chromosomal gene in all species examined and Etb is plasmid borne. Evidence suggests that these genes were brought to the cell on mobile elements similar to the pathogenicity islands recently described in S. aureus. Mapping of the unique DNA surrounding these elements both on the chromosome and plasmid will provide important insights into the heterogeneity and organization of the staphylococcal genome.

Recent Publications: 

Zhang, S., J. J. Iandolo and G. C. Stewart. 1998. The enterotoxin D plasmid of Staphylococcus aureus encodes a second enterotoxin determinant (sej). FEMS Microbiology Lett. 168: 227-233.

Monday, S., G. Vath, W. Ferens, C. Deobald, J. Rago, P. J. Gahr, J. J. Iandolo, S. K. Chapes, M. Jenkins, W. C. Davis, D. Ohlendorf, P. Schlievert and G. A. Bohach. 1999. Unique superantigen activity of staphylococcal exfoliative toxins. J. Immunol. 162: 4550-4559.

Crupper, S. S., V. Worrell, G. C. Stewart and J. J. Iandolo.1999. Cloning and expression of cadD, a new cadmium resistance gene of Staphylococcus aureus. J. Bacteriol. 181: 4071-4075.

Iandolo, J. J. 2000. Genetic and physical map of the genome of Staphylococcus aureus 8325. IN: Gram Positive Pathogens. Eds. V. Fischetti, R. Novick, J. Ferretti, D. Portnoy and J. Rood. ASM Press.

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