The Physics of Plasmid Transfer on Microbial Colonies
- Event time: 1:00pm
- Event date: 26th January 2015
- Speaker: Jakub Pastuszak (Formerly School of Physics & Astronomy, University of Edinburgh)
- Location: Room 2511, James Clerk Maxwell Building (JCMB) James Clerk Maxwell Building Peter Guthrie Tait Road Edinburgh EH9 3FD GB
In addition to chromosomal DNA, many bacteria contain small pieces of DNA called plasmids. Plasmids often carry genes that provide resistance to antimicrobial drugs. Consequently, plasmid transfer (conjugation) between unrelated bacteria is an important factor contributing to the spread of antibiotic resistance. Using a computer model and simple calculations I have studied how the physics of inter-bacteria interactions affects the rate of plasmid transfer between adjacent cells in expanding bacterial colonies. In my talk, I will show that, although neutral (no fitness cost) plasmids may eventually spread to the whole colony, this process is hindered by spatial expansion and is thus very slow. In addition, mechanical forces acting between the cells may further decrease the rate of plasmid transfer to negligible levels.
This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..