Deconstruction of archaeal genome depict strategic consensus in core pathways coding sequence assembly

Area of Science:

• Genomics and Bioinformatics
• Microbial Physiology
• Molecular Evolution

Background:

• Archaea, a domain of single-celled organisms, display diverse physiological characteristics, including variations in oxygen tolerance and energy metabolism.
• Understanding codon usage patterns is crucial for deciphering gene expression regulation and evolutionary adaptations in microbial genomes.

Purpose of the Study:

• To investigate the diversity and similarity in codon usage patterns across 71 archaeal species representing various taxonomic classes and physiological types.
• To explore the relationship between codon usage, gene expression, and physiological attributes, particularly oxygen tolerance and metabolic strategies.
• To identify similarities in the design of core cellular pathways within the domain Archaea.

Main Methods:

• Performed comprehensive in silico analysis of 71 archaeal species.
• Analyzed codon utilization patterns, constructed hierarchical linear models of codon usage, and examined codon pair preferences.
• Utilized Nc-plots to visualize physiological variations and compared codon usage between whole genomes and core cellular pathways.

Main Results:

• Identified a trend towards biased synonymous codon usage in core cellular pathways across archaea.
• Observed that aerobic archaeal species have greater freedom in regulating expression levels beyond codon bias, potentially due to enhanced metabolic activity in oxygen-rich environments.
• Found striking similarities in Open Reading Frame (ORF) structuring among taxonomically related archaeal species, with codon bias being a major determinant of gene expression in anaerobic species.
• Detected significant species-specific and pathway-specific differences in codon pair usage between whole genomes and vital cellular pathways, suggesting optimization for translation accuracy.
• Revealed a codon-pathway interaction influencing codon design, with the transcription pathway showing a distinct coding frequency signature.

Conclusions:

• Codon usage bias plays a significant role in gene expression regulation across the domain Archaea, with variations observed between aerobic and anaerobic species.
• Physiological adaptations, such as oxygen tolerance, correlate with differences in expression regulation strategies.
• The observed codon-pathway interactions and ORF structuring suggest evolutionary optimization for efficient and accurate protein synthesis in archaea.