Similar mutation rates but different mutation spectra in moderate and extremely halophilic archaea
Abstract
Archaea are a major part of Earth’s microbiota and extremely diverse. Yet, we know very little about the process of mutation that drives such diversification. To expand beyond previous work with the moderate halophilic archaeal species Haloferax volcanii, we performed a mutation-accumulation experiment followed by whole-genome sequencing in the extremely halophilic archaeon Halobacterium salinarum. Although Hfx. volcanii and Hbt. salinarum have different salt requirements, both species have highly polyploid genomes and similar GC content. We accumulated mutations for an average of 1250 generations in 67 mutation accumulation lines of Hbt. salinarum, and revealed 84 single-base substitutions and 10 insertion-deletion mutations. The estimated base-substitution mutation rate of 3.99 × 10−10 per site per generation or 1.0 × 10−3 per genome per generation in Hbt. salinarum is similar to that reported for Hfx. volcanii (1.2 × 10−3 per genome per generation), but the genome-wide insertion-deletion rate and spectrum of mutations are somewhat dissimilar in these archaeal species. The spectra of spontaneous mutations were AT biased in both archaea, but they differed in significant ways that may be related to differences in the fidelity of DNA replication/repair mechanisms or a simple result of the different salt concentrations.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 15, 2022
- Source ID
- 10.1093/g3journal/jkac303
Entities
People
- Huseyin Ozgur Ozdemirel
- Michael Lynch
- Sibel Küçükyıldırım
Organizations
- Arizona State University
- Army Research Office
- Hacettepe University
- National Institutes of Health
- TÜBİTAK