I am interested in microbial diversity and bacterial adaptations to the environment. Historically bacterial communities have been identified through culturing techniques, but research has shown that we can culture less than 1% of bacteria in the environment, thus we still know little about the composition of many bacterial communities. My research projects currently focus on two environments, the Siberian permafrost and the prairie phyllosphere (leaf surfaces).

The Siberian permafrost is an extreme environment because of the low temperatures, low nutrient availability and small amount of unfrozen water. This area however, is teeming with bacterial life. We are investigating the microbial diversity in the Siberian permafrost through culture-dependent and culture-independent methods. We have isolated over 100 bacterial strains using a variety of media, and a set of these isolates is being characterized for the ability to grow at low and high temperatures (-4 C to 37 C), and the ability of these strains to tolerate high salt concentrations. We are also determining if the icl gene (which encodes for isocitrate lyase) of these microorganisms contains known cold-adaptations. A 16S clone library has been generated to study the bacterial diversity through culture-independent methods. Finally we are studying the ability of one permafrost isolate (Psychrobacter arcticus) to form biofilms and we will determine the genes important for biofilm formation thro ugh transposon mutagenesis.

I am beginning to study the bacterial communities found in the prairie phyllosphere at the Conrad Environmental Research Area (CERA). Very few studies have investigated the bacterial diversity in the phyllosphere, which is an extreme environment because of the UV exposure, changing temperatures and low water availability. Projects in my lab will study the bacterial diversity by developing new culturing techniques and through culture-independent methods; such as t-RFLP and 16S clone libraries. Other independent projects relating to these general themes are possible.

• Fall
  BIO-251: Molecules, Cells and Organisms, with Lab
  BIO-395: Special Topic, "Environmental Microbiology: How Microbes Impact the Environment"
• Spring
  BIO-150: Introduction to Biological Inquiry, "Survivor"

• Shanks, R. M. Q., N. Caiazza, S. Hinsa, C. Toutain, and G. A. O'Toole. 2006. Saccharomyces cerevisiae-based molecular tool kit for manipulation of genes from gram-negative bacteria. Appl Env Microbiol. 72:5027-36
• Hinsa, S.M. and G.A. O'Toole. 2006. Biofilm formation by Pseudomonas fluorescens WCS365: a role for LapD. Microbiol. 152:1375-1383.
• Hinsa, S.M., and G.A. O'Toole. 2004. Mechanisms of adhesion by Pseudomonas, In: The Pseudomonads, J.L. Ramos (ed.), Kluwer Academic/Plenum Publishers, 699-720.
• Hinsa, S.M., M. Espinosa-Urgel, J.L. Ramos, and G.A. O'Toole. 2003. Transition from reversible to irreversible attachment during biofilm formation by Pseudomonas fluorescens WCS365 requires an ABC transporter and a large secreted protein. Mol. Microbiol., 49:905-918.