Australian Structural Biology Computing community meeting
Purpose of meeting:
- Community meeting / invited speaker series (5 x a year, every 2 months)
- Hear from other researchers about how they approach and leverage computational structural biology
- Learn more about recent developments in bioinformatics that impact structural biology
BioCommons are thrilled to welcome Dr Biswa Prasanna Mishra, Research Fellow at the Griffith University Institute for Biomedicine and Glycomics as the guest speaker for our next Australian Structural Biology Computing community meeting.
Dr Mishra will be presenting ‘Molecular characterisation of the Bacillus subtilis SpbK antiphage defence system’.
All are welcome to join the discussion today (Wednesday 11 March) at 1pm AEDT.
View the agenda and find out how to join here: https://lnkd.in/gwQsjgsV
Presentation
“Molecular characterisation of the Bacillus subtilis SpbK antiphage defence system”
Dr Biswa Prasanna Mishra, Research Fellow at the Griffith University Institute for Biomedicine and Glycomics
Bacteria have a variety of mechanisms for limiting predation by phages. SpbK is a Toll/interleukin-1receptor (TIR) domain-containing antiphage defence protein from Bacillus subtilis that provides protection against the temperate phage SPB via abortive infection. Here we structurally characterise SpbK and its interaction with SPB protein YonE. We demonstrate that SpbK is an NADase that produces both ADP-ribose (ADPR) and canonical cycil ADPR with a N1-glycosidic bond (cADPR, also referred to as N1-cADPR). Combining cryoEM, in silico predictions, site-directed mutagenesis, and phage infection assays, we show that formation of two-stranded head-to-tail assemblies of SpbK TIR domains is required for both NADase activity and antiphage defence. We also demonstrate that YonE is a dodecameric portal protein that activates the NADase function of SpbK by facilitating TIR domain clustering. Collectively, our results provide insight into how bacterial TIR NADase recognise phage infection.
