• Primary Faculty Profiles
• Adjunct Faculty Profiles
• Crane, John, M.D., Ph.D., Assistant Professor
• Genco, Robert, Ph.D., Distinguished Professor
• Gill, Steven, Ph.D.
• Knight, Paul, M.D. and Ph.D., Professor
• Lesse, Alan, Ph.D., Professor
• Murphy, Timothy, Ph.D., Professor
• O'Brian, Mark, Ph.D., Professor
• Rittenhouse-Olson, Kate, Ph.D., Associate Professor
• Russo, Thomas, Ph.D., Assistant Professor
• Departmental Publications
• Career Opportunities
• The Witebsky Center
• Seminars

Faculty and Research

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Education:

1989 - 1995, Postdoc, The Johns Hopkins Univ. School of Medicine
1989, Ph.D., Kansas State University
1983, M.S., North Dakota State University
1981, Bachelor of Science, South Dakota State University

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Research Interests:

Our research interests are centered around microbial pathogens and the impact of human microbial flora on human health and disease.  The current emphasis is on the following research projects:

Virulence determinants of Staphylococcus aureus. 
Staphylococcus aureus is one of the most successful human pathogens, asymptomatically colonizing over 2 billion individuals worldwide and capable of causing invasive and deadly opportunistic infections.  We are using genomic approaches to identify virulence determinants associated with S. aureus infections and determine their roles in pathogenicity.  The numerous putative virulence factors we have identified include toxins, bacterial surface proteins that mediate adhesion to host tissue as well as putative regulatory elements and genes with possible roles in evasion of innate immunity.  We are currently using in vivo and in vitro experimental approaches to verify the functions of these genes.

Evolution of virulence within the Staphylococci. 
In addition to Staphylococcus aureus, the Staphylococcal family includes several species which are emerging as pathogens of clinical relevance.  We are currently focused on two species, Staphylococcus epidermidis and Staphylococcus lugdunensis, and the contribution of vertical and horizontal genome evolution to their increased virulence.  In S. epidermidis, we have identified a putative pathogenicity island (SePI), which appears to have been acquired by cross-species mobilization from S. aureus.  We are attempting to determine the mobilization mechanism of the SePI and its role in virulence.  Staphylococcus lugdunensis has only recently emerged as a significant pathogen and we have limited knowledge of its virulence mechanisms.  As a first step toward identifying these mechanisms, we have sequenced the genomes of two S. lugdunensis isolates, one from a native endocarditis valve infection and the second from a prosthetic valve infection.

Genome diversity of the oral Streptococci
The oral Streptococci (also referred to as Viridans group streptococci or VGS) are most often commensal residents of the oral cavity, where they are pioneering colonizers of the complex multi-species biofilm that is essential for oral health.  In addition to their central role in the oral cavity, VGS are also significant causative agents in infective endocarditis.  Work in our laboratory is currently focused on a member of the VGS named Streptococcus gordonii.  The ability of clinical S. gordonii isolates to cause infective endocarditis is associated with their resistance to killing by polymorphonuclear leukocytes (PMN).  We are using array Comparative Genomic Hybridization (aCGH) and other genomic approaches to examine both resistant and susceptible S. gordonii isolates and identify genes responsible for these phenotypes. 

Association of oral microbial flora with oral cancer
Our most recent effort is focused on exploring the relationships between the complex oral microbial community and oral cancer.  In the initial phases of this project, we are using 16S rDNA phylogenetic analysis to examine bacterial populations within multiple oral sites of patients with oral cancer, including tumor surfaces and deep tumor tissue.  We have successfully identified possible oral cancer associations with both known and novel bacteria and are currently examining the role of these bacteria in tumor initiation or progression. 

Infectious Disease and Genomics Laboratory at the New York State Center of Excellence in Bioinformatics and Life Sciences.
I am co-director of the Infectious Disease and Genomics Laboratory (IDG), which utilizes high-throughput genomic DNA sequencing and Affymetrix microarray approaches for the study of human bacterial and viral pathogens.  Within our IDG laboratory, we have a next-generation Roche 454-FLX DNA sequencer, an Affymetrix genotyping and expression system and an Applied Biosystems 3130xl capillary DNA sequencer.  We welcome scientific collaborations or will provide services on a fee-for-service basis.

Relevant references:

Gill SR, Fouts DE, Archer GL, Mongodin EF, DeBoy RT, Ravel J, Paulsen IT, Kolonay JF,  Brinkac L, Beanan M, Dodson RJ, Daugherty SC, Madupu R, Angiuoli SV, Durkin AS, Haft DH, Vamathevan J, Khouri H, Utterback T, Lee C, Dimitrov G, Jiang L, Qin H, Weidman J, Tran K, Kang K, Hance IR, Nelson KE,  Fraser CM.  Insights on evolution of virulence and resistance from the complete genome analysis of an early methicillin resistant Staphylococcus aureus and a biofilm producing methicillin resistant Staphylococcus epidermidis. J Bacteriology  2004; 187:2426-2438.

Diep, BA, Gill SR, Chang RF, Phan TH, Chen J, Davidson MG, Lin F, Lin J, Carleton HA, Mongodin EF, Sensabaugh GF, Crim D, Perdreau-Remington F. The complete genome sequence of USA300, A multidrug-resistant hypervirulent community-acquired methicillin-resistant Staphylococcus aureus strain.  Lancet 2006;367:731-739.

Gill SR, Pop M, DeBoy RT, Eckburg PB, Turnbaugh PJ, Samuel BS, Gordon JI, Relman DA, Fraser-Liggett CM, Nelson KE.  Metagenomic analysis of the human distal gut microbiome.  Science 2006; 312:1355-1359.

Fowler VG Jr, McIntyre LM, Nelson CL, Kreiswirth BN, Monk A, Archer GL, Naidich S, Remortel B, Rude T, Reller LB, Corey GR, Gill SR. Potential associations between Virulence and bacterial genotype in Staphylococcus aureus.  J Infect Dis 2007;196:738-747.

Vickerman MM, Iobst S, Jesionowski AM, Gill SR. Genome-wide transcriptional changes in Streptococcus gordonii in response to competence signaling peptide. J Bacteriol  2007;189:7799-7807.

Russo TA, Beanan JM, Olson R, MacDonald U, Luke NR, Gill SR, Campagnarii AA.  Rat pneumonia and soft-tissue infection models for the study of acinetobacter baumannii biology.  Infect Immun  2008; 76(8):3577-3586.