Question

Sequence comparison of which of the following genes is used as a measure of evolutionary divergence across bacterial species?

• A. pbpG
• B. slyD
• C. 16S rRNA
• D. 18S rRNA

Hint:

16S rRNA → Prokaryotic phylogeny; 18S rRNA → Eukaryotic phylogeny.

Answer 1

The Correct Option is C

Step 1: Importance of gene markers.
For bacterial phylogenetic studies, highly conserved genes are required to trace evolutionary relationships across species.
Step 2: Role of 16S rRNA.
The 16S ribosomal RNA (rRNA) gene is universally present in bacteria, highly conserved, and contains both conserved and variable regions.
- Conserved regions help in universal primer design.
- Variable regions allow differentiation among bacterial species.
Step 3: Exclude other options.
- pbpG and slyD are not standard markers for evolutionary divergence.
- 18S rRNA is used in eukaryotes (not bacteria).
Step 4: Conclusion.
Hence, the 16S rRNA gene is the gold standard for measuring bacterial evolutionary divergence.
Final Answer: \[ \boxed{\text{16S rRNA is used for bacterial evolutionary divergence studies.}} \]