RT Journal Article SR Electronic T1 RocS drives chromosome segregation and nucleoid occlusion in Streptococcus pneumoniae JF bioRxiv FD Cold Spring Harbor Laboratory SP 359943 DO 10.1101/359943 A1 Chryslène Mercy A1 Jean-Pierre Lavergne A1 Jelle Slager A1 Adrien Ducret A1 Pierre Simon Garcia A1 Marie-Francoise Noirot-Gros A1 Nelly Dubarry A1 Julien Nourikyan A1 Jan-Willem Veening A1 Christophe Grangeasse YR 2018 UL http://biorxiv.org/content/early/2018/07/03/359943.abstract AB Segregation of replicated chromosomes in bacteria is poorly understood outside some prominent model strains and even less is known about how it is coordinated with other cellular processes. Here we report that RocS is crucial for chromosome segregation in the opportunistic human pathogen Streptococcus pneumoniae. RocS is membrane-bound and interacts both with DNA and the chromosome partitioning protein ParB to properly segregate the origin of replication region to new daughter cells. In addition, we show that RocS interacts with the tyrosine-autokinase CpsD required for polysaccharide capsule biogenesis, which is crucial for S. pneumoniae’s ability to prevent host immune detection. Altering the RocS-CpsD interaction drastically hinders chromosome partitioning and cell division. Altogether, this work reveals that RocS is the cornerstone of an atypical nucleoid occlusion system ensuring proper cell division in coordination with the biogenesis of a protective capsular layer.