title: Characterization of the cea gene of the ColE7 plasmid.
abstract: The complete nucleotide sequence (1731 nucleotides) of the gene encoding colicin E7 (cea) of plasmid ColE7-K317 was determined. This sequence encoded a deduced polypeptide of 576 amino acids of molecular weight 61349 Da. Comparison of the nucleotide and amino acid sequences of cea E7 with those of other E-group colicins revealed that colicin E7 was closely related to colicin E2, both in gene sequence and in predicted secondary structure of the deduced protein. Judging from the results of cross-immunity tests, we postulated that ColE7 is probably a proximate ancestor of ColE2 and ColE8. Based on results from colicin production tests on cells harboring a 5' end deleted form of the cea E7 gene, we propose that a previously unknown, non-inducible promoter may be involved in regulation of the constitutive expression of the cea E7 gene.
authors.affiliation: Institute of Clinical Medicine, National Yang-Ming Medical College, Taipei, Taiwan, Republic of China.
authors.forename: B W
authors.initials: BW
authors.lastname: Soong
authors.forename: F M
authors.initials: FM
authors.lastname: Lu
authors.forename: K F
authors.initials: KF
authors.lastname: Chak
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D005075:Biological Evolution; D003087:Colicins / Q000302:isolation & purification*; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D010957:Plasmids; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D013014:SOS Response, Genetics; D016415:Sequence Alignment
chemical_list: D003087:Colicins