Spatial Organization of Biological Fuctions | BPS Thematic Meeting

Spatial Organization of Biological Functions Meeting

Tuesday Speaker Abstracts

BACTERIAL 3D GENOME FOLDING: LESSONS FROM PSEUDOMONAS CHROMOSOME Mounia Kortebi 1 ; Laura Lebrun 1 ; Jean-Noël Lorenzi 1 ; Isabelle Vallet 1 ; Alicia Nevers 1 ; Frédéric Boccard 1 ; Stéphanie Bury-Moné 1 ; Virginia Lioy 1 ; 1 Institute for Integrative Biology of the Cell (I2BC), Genome Biology, Gif-sur-Yvette, France The large-scale organization of the bacterial chromosome usually relies on the activity of a single SMC complex. In several species, this complex also ensures proper chromosome segregation. Unusually, Pseudomonas aeruginosa encodes two SMC complexes: Smc-ScpAB and MksBEF. These complexes display distinct activities on chromosome management and act hierarchically. Using genomics, genetics and fluorescence microscopy, we dissected the coordination between these SMC complexes and DNA replication. Furthermore, to determine whether the coexistence of two SMC complexes is conserved across the Pseudomonas genus, we performed comparative genomics on 210 complete genomes. This analysis revealed major lineage-specific differences in genome size and structure, including a striking expansion of a poorly conserved, low-expression region near the replication terminus, especially in the P. fluorescens group. Together, our results link 1D genome evolution with 3D chromosome folding in Pseudomonas.

CHROMOSOME DYNAMICS DURING BATERIAL RECOMBINATION Anjana Badrinarayanan National Centre for Biological Sciences, India No Abstract

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