Open AccessMolecular cloning, nucleotide sequence, and expression of shl, a new gene in the 2-minute region of the genetic map of Escherichia coli
Author(s) -
Gilles M. Leclerc,
G Noël,
Gabriel R. Drapeau
Publication year - 1990
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.172.8.4696-4700.1990
Subject(s) - biology , gene , open reading frame , nucleic acid sequence , structural gene , repressor , genetics , transcription (linguistics) , microbiology and biotechnology , plasmid , escherichia coli , peptide sequence , regulator gene , lac repressor , gene expression , linguistics , philosophy
Cells of Escherichia coli that harbor supH (an allele of the wild-type gene serU) are sensitive to UV irradiation and temperature and appear to have an impaired cell division control mechanism. We found that a gene located at the 2-min region, designated shl, inhibited the growth of supH-harboring cells when carried by a high-copy-number plasmid, whereas the same plasmid had no visible effect when present in parental cells. The amino acid sequence predicted from the nucleotide sequence of the shl gene indicated a similarity to the GalR and LacI repressor proteins, suggesting it is a transcription regulator. The sequence between the promoter and the structural genes revealed the presence of a short open reading frame of 28 amino acid residues followed by a segment of 81 base pairs. These structural features suggest that a transcription antitermination mechanism may be involved in the regulation of expression of the shl gene. The possibility that shl is a regulator of serU is discussed.