The DNA Transfer Region of Bacteroides Conjugative Transposons Tc(r)Em(r)DOT and Tc(r)ERL

157 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1999.This dissertation presents the first detailed study of the conjugal transfer genes found on a conjugative transposon. The complete sequence of a functional transfer region is presented and comparative analysis is made between the transfer gene sequences of several conjugative transposons. Two of the newly discovered transfer genes possess sequence homology with genes from other transfer systems and the significance of this relationship is discussed. Additionally, the first nucleotide and amino acid level homology between the Bacteroides conjugative transposons and the NBUs is revealed. Transfer of both NBUs and conjugative transposons depends on the regulatory protein RteB, but little is known about how RteB mediates its effect on both elements. This homology may provide a clue about this mechanism of regulation. Mutational analysis of the transfer region has so far revealed genes necessary for self-transfer of the conjugative transposon, but not plasmid mobilization. Antibodies for four of the transfer proteins have been used in protein localization studies to show that these gene products are localized to the cell membrane. The antibodies have also helped to demonstrate that a mutation in one of the transfer proteins results in increased production of the other transfer proteins. This mutation provides new insights into the complex regulatory system that controls transfer as mediated by the conjugative transposons. The combination of sequence data and a working transfer model will allow us to better compare and contrast the Bacteroides conjugative transposons with other systems for DNA transfer and protein export while also providing new insights into the process of DNA transfer in general.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD