The atypical peptidoglycan of Francisella tularensis

• DOI: 10.55632/pwvas.v97i2.1149
• Publication Date: 2025-04-08T15:24:46Z
• Authors: Hayden Hess; Melanie Sal; Stuart Cantlay; Joseph Horzempa
• Keywords: Tularemia; Francisella

Peptidoglycan (PG), the main component of bacterial cell wall, plays a fundamental role in maintaining shape, integrity, and resistance to osmotic pressure. Preliminary observations suggested that unlike typical bacteria, Francisella tularensis infrequently produces detectable PG while growing rich liquid media. However, increasing salt concentration induces production all bacteria. In this study, we confirmed extended these by incubating bacteria with fluorescent D-alanine (which integrates into peptide stem during synthesis). Fluorescence microscopy revealed very few F. produce low media, seemingly individual layer high A transposon mutagenesis screen yielded sixteen mutant isolates capable immediately on Interestingly, isolate Tn4 did not appear synthesize any levels regardless level Sequencing subsequent abrogated expression FTL_1305 (mviN). To identify candidate genes responsible for peptidoglycan modulation, RNA-seq was conducted cultured or conditions. This analysis several ORFs interest. Future LC/MS studies will examine makeup muropeptides investigate whether composition tetrapeptide crosslinks is modulated.