Roles of non-Cas nucleases in Type III-A CRISPR-Cas immunity

The overuse of antibiotics has led to a new wave of resistant bacterial pathogens insensitive to current antibiotics. Staphylococcus species are ubiquitous residents of human skin that can acquire and disseminate antibiotic resistance genes (ARGs) through horizontal gene transfer (HGT). Therefore, it is essential to understand cellular processes that naturally block HGT and prevent the transfer of ARGs. One such process is mediated by Clustered Regulatory Interspaced Short Palindromic Repeats (CRISPRs) and their CRISPR-associated (Cas) proteins. CRISPR-Cas systems are a class of prokaryotic immune systems that use small CRISPR RNAs (crRNAs) as guides and Cas nucleases as weapons to detect and destroy mobile genetic elements, including plasmids and bacteriophages. The work in this thesis investigates the mechanism of CRISPR-Cas immunity using S. epidermidis RP62a, a commensal opportunistic pathogen, as the model organism. This research investigates and proves the central hypothesis that the Type III-A CRISPR-Cas system collaborates with housekeeping nucleases to mount a successful defense against genetic invaders.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Microbiology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2023

Author dc:creator

• Chou Zheng, Lucy

Contributors dc:contributor

• Hatoum-Aslan, Asma
• Kuzminov, Andrei
• Mera, Paola E.
• Nair, Satish K.

• Crispr-cas10
• Type Iii-a Crispr-cas
• Cas10-csm
• Crispr-cas
• Degradosome, Staphylococci
• Staphylococcus Epidermidis
• Pnpase
• Rnase R
• Rnase J2
• Nhi
• Anti-phage Defense.

Statement dc:rights

• Copyright 2023 Lucy Chou Zheng

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/121357

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F121357