The physical map of the whole E. coli chromosome: Application of a new strategy for rapid analysis and sorting of a large genomic library

The narK gene product participates in nitrate transport induced in Escherichia coli nitrate‐respiring cells

“…The narK gene was subcloned from pNR26 [13] originating from Xl3H6, which is one of the clones in the E. co/i chromosome library of Kohara et al [23]. The plasmid pNR53 bearing the nurK+ gene was constructed by subcloning a 2.2 kb XhoI-NcoI fragment of pNR26 into the EcoRI-NcoI sites of pACYCl84DP (obtained by deleting from pACYCl84 a 0.41 kb PvuII fragment bearing the promoter and N-terminal coding region of the cut gene) after filling an end with Tq DNA polymerase.…”

Precise physical mapping of theEscherichia coli pheU transcription unit

“…Under our conditions, this fragment directs the synthesis of a l l0-nucleotide-long RNA which probably corresponds to a transcript starting at the putative promoter and terminating at the putative rho-independent terminator. The restriction map of the pEB I0 plasmid is homolo; gous to that one of pMU393 [6] and of the plD2 [7] except the inversion of a 3.6 kb Sall fragment to be in accordance with the Escherichia coli chromosomal map [8]. The nucleotide sequence is identical to that one described [6,9] for the tRNA ~' )' gone mapped to 94 min.…”

“…kb EcoRI-Sall restriction fragment of pCS8, cloned in M 13mp8, has been used for sequencing from the SalI site over 300 nucleotides as described in section 2. The tRNA ph~ structural sequence is preceded by a promoter and followed by a rho-independent termina- Restriction maps of recombinant plasmids described in the text rclativc to the whole E,~'cherichia co/i chromoson~al map as described [8,9].…”

ClpX and ClpP are essential for the efficient acquisition of genes specifying type IA and IB restriction systems

“…Other phages were the following clp derivatives of the vector NM1151 . The clpP þ X þ ( NM1357) includes a 6.2 kb BamHI fragment from the Kohara phage 148 (Kohara et al, 1987), a clpX ::kan derivative ( NM1361) has the homologous BamHI fragment from NM840clpX , and a clpP ::cat derivative ( NM1359) was made by inserting the HindIII-BamHI fragment from pWPC16 (Maurizi et al, 1990); this clpP ¹ X þ phage, like pWPC16, has a deletion that extends from within the tig gene, upstream of clpP into bolA, leaving clpX as the only functional gene within the cloned DNA fragment. clpP ::cat clpX ::kan ( NM1362) was made in vivo by excision of the prophage from the clpP ::cat clpX ::kan double mutant (SG22129) lysogenic for clpP ::cat ( NM1359).…”