title: Horizontal transfer of nonconjugative plasmids in a colony biofilm of Escherichia coli.
abstract: We tested the possibility of nonconjugative lateral DNA transfer in a colony biofilm of mixed Escherichia coli strains. By simply coculturing a plasmid-free F(-) strain and another F(-) strain harboring a nonconjugative plasmid in a colony biofilm on antibiotic-free agar media, transformed cells were produced within 24-48 h at the frequency of 10(-10)-10(-9) per recipient cell. PCR analysis of the transformed cells demonstrated the occurrence of lateral plasmid transfer. These cells survived until at least day 7 under antibiotic-free conditions. Liquid cultures of the same strains in Luria-Bertani broth produced no or few transformants, suggesting the importance of colony-biofilm formation for plasmid transfer. This is a novel line of evidence indicating that nonconjugative, nonviral horizontal gene transfer can occur between E. coli cells.
authors.affiliation: Faculty of Human Life and Environment, Nara Women's University, Kitauoya-nishi-machi, Nara, Japan. smaeda@cc.nara-wu.ac.jp
authors.forename: Sumio
authors.initials: S
authors.lastname: Maeda
authors.forename: Miki
authors.initials: M
authors.lastname: Ito
authors.forename: Tsuyako
authors.initials: T
authors.lastname: Ando
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ishimoto
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Fujisawa
authors.forename: Hitomi
authors.initials: H
authors.lastname: Takahashi
authors.forename: Akiko
authors.initials: A
authors.lastname: Matsuda
authors.forename: Akiko
authors.initials: A
authors.lastname: Sawamura
authors.forename: Shiho
authors.initials: S
authors.lastname: Kato
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D003470:Culture Media; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development; D022761:Gene Transfer, Horizontal; D010957:Plasmids / Q000235:genetics*; D014169:Transformation, Bacterial / Q000235:genetics*
chemical_list: D003470:Culture Media