Molecular cloning of the EnvC gene of Escherichia coli.

DNA fragments complementing the envC mutation could be isolated by cloning chromosomal DNA in the vector pUH84. When the frequencies of transformation and the frequencies of restoring the envC phenotype were compared, the high copy number hybrid plasmids complemented with a frequency of 10. After subcloning the envC-complementing DNA fragment into the low copy number plasmid pLG339, efficient complementation was achieved by spontaneous integration of the IS2 element of Escherichia coli. By nucleotide sequence analysis, a potential promoter, a ribosome-binding site, and an unidentified reading frame were detected in the respective DNA fragment. [ABSTRACT FROM AUTHOR]