Liman, Geraldy Lie Stefanus, authorSantangelo, Thomas J., advisorMarkus, Steven, committee memberSchauer, Grant, committee memberSloan, Daniel, committee member2024-09-092025-08-162024https://hdl.handle.net/10217/239230DNA replication is an essential biological process across all life on Earth. For the prokaryotic Archaea domain, which contains organisms that can thrive in inhospitable environments like hydrothermal vents or salt deposits in the Dead Sea, the cell machinery for these conserved processes have acclimated over the course of evolution to encourage survival. While the origin of replication (ori), a predetermined position within the genome where DNA replication starts, is conserved in all Domains, its significance is not equal between them. Surprisingly, the model hyperthermophilic archaeon, T. kodakarensis, replicates its genome without relying on origin-dependent replication (ODR), and instead, relies mostly on recombination-dependent replication (RDR). In fact, the ori in T. kodakarensis is dispensable from the organism without much phenotypic consequence. Although dispensable, ori persists after millions of years of evolution in this organism, suggesting some functional significance under certain conditions. Not to mention, archaeal replisomes are comprised of unique components that are distinct from the other two domains of life, though surprisingly more similar to those found in Eukarya. Central to all replisomes is the activity of the DNA polymerase (DNAP). Most archaeal organisms, except for the Creanarchaea, encode two main replicative DNAPs, the eukaryotic-like B-family DNAP (PolB) and the archaeal-specific D-family DNAP (PolD). In T. kodakarensis, PolD is the essential replicative DNAP while PolB is dispensable. This thesis aims to (1) characterize the activity and regulation of RadA, the main recombinase in Archaea, (2) characterize the exaptation of inteins to regulate DNA replication, (3) delineate the in vivo function(s) of PolB. Furthermore, I hope to further characterize DNA replication in the context of evolutionary biology and how it relates to the three Domains of life.born digitaldoctoral dissertationsengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.DNA replicationinteinhyperthermophileArchaeaTextEmbargo expires: 08/16/2025.