3
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      Replication origin of the Escherichia coli K-12 chromosome: the size and structure of the minimum DNA segment carrying the information for autonomous replication.

      , , ,
      Molecular & general genetics : MGG

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          A DNA fragment containing the replication origin of the Eschericia coli K-12 chromosome was inserted in two correlations at either the BamHI or SalI site of pBR322 DNA. All the resulting hybrid plasmids were found to replicate in both polA and polA+ cells, whereas pBR322 replicates only in polA+ cells. This characteristic provided a method for assaying the autonomously replicating ability (Ori function of the E. coli origin. In order to define the minimum DNA region (ori) that determines Ori function, deletions of various sizes were introduced from either side of the ori-containing segment in the hybrid plasmids by in vitro techniques, and the correlation between the Ori phenotype and nucleotide sequence of the deletion derivatives was analyzed. It was found that the left end of ori is between positions 23 and 35, and the right end is either position 266 or 267 in our nucleotide coordinate (Sugimoto et al., 1979). Therefore, ori is present within a region of minimum 232 base pairs and maximum 245 base pairs in length. The Ori+ and Ori- phenotypes were clearly resolved at both sides of these boundaries by the above assay procedure. To obtain information about the effect of mutations in the internal region of the defined ori stretch, short sequences were inserted or deleted in vitro in the vicinity of several restriction sites within ori on the hybrid plasmids. Most of these plasmids carrying modified sequences showed Ori- phenotype, suggesting that most parts of the ori stretch play important roles in Ori function.

          Related collections

          Author and article information

          Journal
          Mol. Gen. Genet.
          Molecular & general genetics : MGG
          0026-8925
          0026-8925
          Apr 1980
          : 178
          : 1
          Article
          10.1007/BF00267207
          6991883
          48faa4ef-5dda-4be4-81c3-65dab1ba2faf
          History

          Comments

          Comment on this article