Revisiting the Relationships Between Genomic G + C Content, RNA Secondary Structures, and Optimal Growth Temperature

Area of Science:

• Molecular Biology
• Genomics
• Bioinformatics

Background:

• The 20-year-old Galtier and Lobry study found no link between genomic GC content and prokaryotic optimal growth temperature (OGT).
• However, they observed a correlation between RNA secondary structures and OGT.

Purpose of the Study:

• To revisit the foundational work of Galtier and Lobry on genomic content, RNA structure, and OGT.
• To explore the evolution of these research questions over two decades.
• To highlight the broader impact of the original manuscript.

Main Methods:

• Analysis of genomic G+C content in prokaryotes.
• Assessment of RNA secondary structures (rRNA stems, tRNAs) and their relationship with OGT.
• Review of subsequent research and applications stemming from the original findings.

Main Results:

• Genomic G+C content does not correlate with OGT.
• Increased G+C content in structured RNA, especially double-stranded regions, correlates with higher OGT.
• These relationships have been validated and led to applications in OGT prediction and ncRNA identification.

Conclusions:

• The relationship between structured RNA G+C content and OGT is a robust finding in molecular evolution.
• The original Galtier and Lobry manuscript has had a lasting impact, influencing diverse research areas.
• This work underscores the importance of RNA structure in understanding microbial physiology and evolution.