2007 Annual Report 1a.Objectives (from AD-416) The objective of this cooperative research project is to perform genome analysis of Leptospira species to identify genetic differences and variation in gene expression under different experimental conditions. A variety of approaches will be used, including genome sequencing, bioinformatics, development of microarrays, and analysis of proteomes. 1b.Approach (from AD-416) Each laboratory independently determined the genome sequence of strains of Leptospira borgpetersenii serovar hardjo. In addition, the laboratory at Monash University has revised the annotation of two Leptospira interrogans genomes. Comparative sequence analysis using bioinformatics will be used to identify alterations in genes and attempts will be made to correlate these genetic differences with altered characteristics of the bacteria. Genome sequence data will be used to design and produce microarrays that will be used to identify changes in gene expression under different environmental conditions. Protein expression patterns will be determined using proteomic analysis techniques and immunological analysis. 3.Progress Report This report serves to document research conducted under a non-funded cooperative agreement with Monash University. Additional details of this research can be found in the report for the parent project 3625-32000-081-00D (Genomic and Immunological Analysis of Spirochetes). In FY2007, Leptospira interrogans microarrays were used by collaborators to complete studies demonstrating differential gene expression in response to changes in osmolarity. This work was submitted for consideration and published. Current studies include analysis of nutrient deprivation on gene expression. This work is designed to mimic the events relative to release of bacteria into the environment, a key step in disease transmission in L. interrogans, and a major difference in the transmission mechanisms used by L. interrogans and L. borgpetersenii. Progress under this NFCA is monitored by periodic conference calls and e-mails. Conference calls are organized at varying periods, often at least once a month, sometimes weekly. Data generation can be monitored by secure Internet access to a server hosted by the cooperator.