Cell Division Cycle and Chromosomal DNA Replication of Higher Plants and Other Eukaryotes, EMBO (European Molecular Biology Organization) Workshop on Molecular Basis of Bacterial Growth and Division, Segovia, Spain, September 27-October 1, 1987: Foreign Trip Report

摘要

The details of DNA replication initiation in E. coli are gradually being understood at the enzymatic level. An in vitro assay system using the minimal 246 base origin has defined several separate steps so far. In vivo, the initiation process is complex because it involves the interaction of transcripts of genes in the origin region and specific DNaA binding boxes. The mechanism of replication termination is unknown. There is strong evidence for specific termination sequences but these too, are complicated by genes located in the terminus region. It is clear that sequences used as replication origins and termini are specific for a given species. Therefore, what is true for E. coli need not to be the rule for B. subtilis or Pseudomonas. Separation (cell division) and replication termination are tightly linked but the mechanisms responsible for this linkage remain a mystery even though many septation genes are identified. Likewise, the genes involved in plasmid or phage partitioning are known but how their products interact with the cell membrane to achieve segregation precision is still explained in hypothetical terms. Cell wall structure, a component of the septation phenomenon, is ripe for neutron diffraction studies. Until this structure is fully delineated, cell division in E. coli will not be understood. (ERA citation 14:006446)