Structure and function of macromolecular machines involved in infection of prokaryotic and eukaryotic cells
Event details
| Date | 25.06.2009 |
| Hour | 12:15 |
| Speaker | Petr Leiman |
| Location |
SV 1717A
|
| Category | Conferences - Seminars |
A majority of bacterial viruses (bacteriophages) use a multicomponent macromolecular machine, called a tail, to infect their host cells. The tail and fibers, which emanate from the tail, coordinate the infection process and allow the phage to penetrate through the multilayered host cell envelope, which consists of the external polysaccharide, two lipid membranes and the intervening peptidoglycan layer. Currently, there are 3 types of tails known and they differ in their complexity and the mode of action. For example, at least 22 genes participate in the assembly of the bacteriophage T4 tail, and the combined size of these genes is greater than the entire genome of adenovirus, which is considered to be a complex eukaryotic virus. Notably, most probably due to the function of the tail, infectivity of phages is much greater than that of eukaryotic viruses and approaches 100% in laboratory conditions.
Evolutionary ancestry of tails represents an unsolved puzzle of microbiology. However, several recent findings suggest that a macromolecular complex resembling a tail is present in bacteria. This structure shows properties of a secretion system, which has been categorized at the Type VI Secretion System (T6SS). The T6SS gene cluster is present in many pathogenic bacteria and has been shown to be a virulence factor for several bacterial pathogens. Remarkably, using this tail-like structure, bacteria are able to translocate large proteins directly into the cytoplasm of eukaryotic cells.
The following topics will be discussed: 1) the structure and function of key proteins from phage tails; 2) the type VI secretion system; 3) possible application of phage tails as tunable antimicrobials.
Links
Practical information
- General public
- Free
Contact
- Prof. Gisou van der Goot - Global Health Institute