Excessive Promoters as Silencers of Genes Horizontally Acquired by Escherichia coli.

ABSTRACT: Horizontally acquired genes are usually transcriptionally inactive, although most of them are associated with genomic loci enriched with promoter-like sequences forming "promoter islands." We hypothesized that lateral DNA transfer induces local mutagenesis, accumulating AT base pairs and creating promoter-like sequences, whose occupancy with RNA polymerase and a specific silencer H-NS suppresses the transcription of foreign genes. Error-prone mutagenesis was implemented for the "promoter island" of a foreign gene appY and the promoter region of an inherent gene dps. Derivatives with changed transcriptional activity were selected using a reporter plasmid pET28_eGFP. Only one cycle of mutagenesis with negative selection suppressed the activity of the main dps promoter to

SUBMITTER: Bykov A 

PROVIDER: S-EPMC7054387 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature