Does the parallel evolution pattern between the replication-segregation proteins and HU have a biological significance?

The bacterial chromosome is a highly compacted nucleoproteic structure, its apparent disordered morphology is difficult to conciliate with newly discovered mechanisms governing the propagation of genetic information between mother and daughter cells. Recent experiments in bacterial genetics. biochemistry and cytology from a number of laboratories are beginning to unravel how at each cell division, DNA replication and segregation proteins interact spatially with specific DNA motifs. to orchestrate replication and movement of replication forks and chromosomes. We propose here a method to confirm and perhaps extend these experiments by in silico protein sequence comparisons and phylogeny. This analysis showed a parallel evolution between the histone-like protein HU and key protein factors involved in DNA replication and chromosome segregation. (C) 2001 Societe francaise de biochimie et biologie moleculaire / Editions scientifiques et medicales Elevier SAS.