Charlie Mo

• Systematic, high-throughput characterization of bacteriophage gene essentiality on diverse hosts
  July 23, 2025
  Jackie Chen, Erick D Nilsen, Chutikarn Chitboonthavisuk, James E Corban, Matthew Yang, Charlie Y Mo, Srivatsan Raman Cell host & microbe
• Bacteriophage infection drives loss of β-lactam resistance in methicillin-resistant Staphylococcus aureus
  July 10, 2025
  My Tran, Angel J Hernandez Viera, Patricia Q Tran, Erick D Nilsen, Lily Tran, Charlie Y Mo eLife
• Deep mutational scanning identifies Cas1 and Cas2 variants that enhance type II-A CRISPR-Cas spacer acquisition
  July 2, 2025
  Raphael Hofmann, Calvin Herman, Charlie Y Mo, Jacob Mathai, Luciano A Marraffini Nature communications
• If you can't beat them, join them: Anti-CRISPR proteins derived from CRISPR-associated genes
  November 14, 2024
  Charlie Y Mo Cell host & microbe
• Systematic, high-throughput characterization of bacteriophage gene essentiality on diverse hosts
  October 17, 2024
  Jackie Chen, Erick D Nilsen, Chutikarn Chitboonthavisuk, Charlie Y Mo, Srivatsan Raman bioRxiv : the preprint server for biology
• Type III-A CRISPR immunity promotes mutagenesis of staphylococci
  April 8, 2021
  Charlie Y Mo, Jacob Mathai, Jakob T Rostøl, Andrew Varble, Dalton V Banh, Luciano A Marraffini Nature
• Advancement of the 5-Amino-1-(Carbamoylmethyl)-1H-1,2,3-Triazole-4-Carboxamide Scaffold to Disarm the Bacterial SOS Response
  January 9, 2019
  Trevor Selwood, Brian J Larsen, Charlie Y Mo, Matthew J Culyba, Zachary M Hostetler, Rahul M Kohli, Allen B Reitz, Simon D P Baugh Frontiers in microbiology
• Type III-A CRISPR-Cas Csm Complexes: Assembly, Periodic RNA Cleavage, DNase Activity Regulation, and Autoimmunity
  December 4, 2018
  Ning Jia, Charlie Y Mo, Chongyuan Wang, Edward T Eng, Luciano A Marraffini, Dinshaw J Patel Molecular cell
• Dynamics of Cas10 Govern Discrimination between Self and Non-self in Type III CRISPR-Cas Immunity
  December 4, 2018
  Ling Wang, Charlie Y Mo, Michael R Wasserman, Jakob T Rostøl, Luciano A Marraffini, Shixin Liu Molecular cell
• If You'd Like to Stop a Type III CRISPR Ribonuclease, Then You Should Put a Ring (Nuclease) on It
  November 17, 2018
  Charlie Y Mo, Luciano A Marraffini Molecular cell
• Non-equilibrium repressor binding kinetics link DNA damage dose to transcriptional timing within the SOS gene network
  June 2, 2018
  Matthew J Culyba, Jeffrey M Kubiak, Charlie Y Mo, Mark Goulian, Rahul M Kohli PLoS genetics
• Inhibitors of LexA Autoproteolysis and the Bacterial SOS Response Discovered by an Academic-Industry Partnership
  December 26, 2017
  Charlie Y Mo, Matthew J Culyba, Trevor Selwood, Jeffrey M Kubiak, Zachary M Hostetler, Anthony J Jurewicz, Paul M Keller, Andrew J Pope, Amy Quinn, Jessica Schneck, Katherine L Widdowson, Rahul M Kohli ACS infectious diseases
• A Small-Molecule Inducible Synthetic Circuit for Control of the SOS Gene Network without DNA Damage
  August 23, 2017
  Jeffrey M Kubiak, Matthew J Culyba, Monica Yun Liu, Charlie Y Mo, Mark Goulian, Rahul M Kohli ACS synthetic biology
• Systematically Altering Bacterial SOS Activity under Stress Reveals Therapeutic Strategies for Potentiating Antibiotics
  August 19, 2016
  Charlie Y Mo, Sara A Manning, Manuela Roggiani, Matthew J Culyba, Amanda N Samuels, Paul D Sniegowski, Mark Goulian, Rahul M Kohli mSphere
• Targets for Combating the Evolution of Acquired Antibiotic Resistance
  May 29, 2015
  Matthew J Culyba, Charlie Y Mo, Rahul M Kohli Biochemistry
• High-throughput mutagenesis reveals functional determinants for DNA targeting by activation-induced deaminase
  July 28, 2014
  Kiran S Gajula, Peter J Huwe, Charlie Y Mo, Daniel J Crawford, James T Stivers, Ravi Radhakrishnan, Rahul M Kohli Nucleic acids research
• Specificity determinants for autoproteolysis of LexA, a key regulator of bacterial SOS mutagenesis
  May 1, 2014
  Charlie Y Mo, L Dillon Birdwell, Rahul M Kohli Biochemistry

Prokaryotic evolution is driven by two fundamental molecular mechanisms: horizontal gene transfer and mutagenesis. Horizontal gene transfer (HGT) involves the movement of large pieces of genetic material between cells and is mediated by mobile genetic elements (MGEs). Mutagenesis, by contrast, is the process during which small changes, such as insertions, deletions, or single base changes, are introduced into a cell’s genetic material. Most mutations are triggered by a variety of sources, including environmental stressors and so-called “pro-mutagenic” cellular processes. Both HGT and mutagenesis are major drivers of bacterial evolution and antimicrobial resistance.

In the recent years, the bacterial adaptive immune system, CRISPR-Cas, was shown to selectively target and eliminate MGEs, thus limiting the movement of genetic material between cells. We have demonstrated that CRISPR-Cas immunity against MGEs can also promote increased mutation rates inside bacteria, enabling them to adapt to stressors that they had not yet been exposed to. These findings raise the fundamental question of how bacteria evolve in the presence of immunity against MGEs. How does the activity of CRISPR-Cas and other defense systems shape genetic variation and bacterial adaptability over time? And conversely, how do variation and selective forces shape the activity of bacterial defense systems?

We focus our efforts on the following broad areas:

1. Examine how anti-phage defense systems, such as CRISPR-Cas, impact bacterial variation and evolution during active immunity

2. Investigate the mechanisms by which key cellular processes, such as transcription, modulate bacterial immunity

3. Study how variation and different selective pressures mold the activity of bacterial defense systems

Start and Promotion Dates

• Assistant Professor: 2023

Education

B.A., Biochemistry, Swarthmore College
Ph.D., Biochemistry & Molecular Biophysics, University of Pennsylvania
Postdoctoral Research, Laboratory of Bacteriology, Rockefeller University

• Doran Goldman – Grad Student
• Angel Hernandez Viera – Grad Student
• Christian Lapitan – Grad Student
• Anna Moyer – Grad Student
• My Tran – Grad Student