Sam Hobbs
Assistant Professor of Biochemistry
Host-virus interactions, Antiviral immunity, Protein structure and Function
Molecular Biology Program
Biological Chemistry Program
Education
B.S. University of Washington
Ph.D. Oregon Health & Science University
Research
The evolutionary arms race between cells and viruses has generated tremendous diversity
in host defense systems and viral immune evasion strategies. Until recently, prokaryotes
and eukaryotes were thought to encode unrelated antiviral immune pathways that arose
independently throughout evolution. However, recent studies have identified numerous
anti-phage defense systems in bacteria that are homologous to eukaryotic innate immune
pathways, revealing unexpected parallels in the fundamental mechanisms of antiviral
immunity in all kingdoms of life.
The overall goal of our research is to explain how conserved molecular rules govern host-virus interactions in all kingdoms of life, with a specific emphasis on the mechanisms host cells use to sense viral infection and the mechanisms viruses use to evade host immunity.
References (Selected Publications)
- Phage protease enzymes activate CBASS antiphage immunity.
Hobbs SJ, Kranzusch PJ. bioRxiv [Preprint]. 2026 Mar 5:2026.03.04.709575. doi: 10.64898/2026.03.04.709575. PMID: 41846949 - Chang RB, Toyoda HC, Hobbs SJ, Hadary R, Richmond-Buccola D, Wein T, Osterman I, Burger N, Chouchani ET, Sorek R, Kranzusch PJ. A widespread family of viral sponge proteins reveals specific inhibition of nucleotide signals in anti-phage defense. Mol Cell. 2025 Aug 21;85(16):3151-3165.e6. doi: 10.1016/j.molcel.2025.07.016. PubMed PMID: 40845805; PubMed Central PMCID: PMC12380128.
- Yirmiya E, Hobbs SJ, Leavitt A, Osterman I, Avraham C, Hochhauser D, Madhala B, Skovorodka M, Tan JMJ, Toyoda HC, Chebotar I, Itkin M, Malitsky S, Amitai G, Kranzusch PJ, Sorek R. Structure-guided discovery of viral proteins that inhibit host immunity. Cell. 2025 Mar 20;188(6):1681-1692.e17. doi: 10.1016/j.cell.2024.12.035. Epub 2025 Jan 23. PubMed PMID: 39855193.
- Hobbs SJ, Nomburg J, Doudna JA, Kranzusch PJ. Animal and bacterial viruses share conserved mechanisms of immune evasion. Cell. 2024 Oct 3;187(20):5530-5539.e8. doi: 10.1016/j.cell.2024.07.057. Epub 2024 Aug 27. PubMed PMID: 39197447; PubMed Central PMCID: PMC11455605.
- Yirmiya E, Leavitt A, Lu A, Ragucci AE, Avraham C, Osterman I, Garb J, Antine SP, Mooney SE, Hobbs SJ, Kranzusch PJ, Amitai G, Sorek R. Phages overcome bacterial immunity via diverse anti-defence proteins. Nature. 2024 Jan;625(7994):352-359. doi: 10.1038/s41586-023-06869-w. Epub 2023 Nov 22. PubMed PMID: 37992756.
- Leavitt A, Yirmiya E, Amitai G, Lu A, Garb J, Herbst E, Morehouse BR, Hobbs SJ, Antine SP, Sun ZJ, Kranzusch PJ, Sorek R. Viruses inhibit TIR gcADPR signalling to overcome bacterial defence. Nature. 2022 Nov;611(7935):326-331. doi: 10.1038/s41586-022-05375-9. Epub 2022 Sep 29. PubMed PMID: 36174646.
- Hobbs SJ, Wein T, Lu A, Morehouse BR, Schnabel J, Leavitt A, Yirmiya E, Sorek R, Kranzusch PJ. Phage anti-CBASS and anti-Pycsar nucleases subvert bacterial immunity. Nature. 2022 May;605(7910):522-526. doi: 10.1038/s41586-022-04716-y. Epub 2022 Apr 8. PubMed PMID: 35395152; PubMed Central PMCID: PMC9117128.