FAQs
1. Can stress conditions increase the rate of horizontal gene transfer?
Yes, stress factors such as UV radiation, nutrient starvation, and exposure to certain antibiotics can trigger bacterial stress responses (like the SOS response), which significantly increase the rates of gene transfer by activating mobile genetic elements and bacteriophages6. This means that stressful environments can accelerate bacterial evolution via HGT.
2. What role do mobile genetic elements (MGEs) play in horizontal gene transfer?
MGEs such as plasmids, transposons, integrative conjugative elements, and gene transfer agents are the vehicles that facilitate HGT by moving genes between bacteria. They carry genes that can confer antibiotic resistance, virulence factors, or metabolic traits, and their activity can be regulated by environmental signals and stress
3. How does horizontal gene transfer affect bacterial diversity and coexistence?
Increasing the rate of HGT can promote species coexistence and enhance microbial diversity by enabling more bacteria to acquire resistance or adaptive traits, helping them survive antibiotic pressure and environmental challenges.
4. Are there natural “hotspots” where horizontal gene transfer is more frequent?
Yes, environments such as hot springs, marine sediments, oil wells, and biofilms are hotspots for HGT due to high microbial density and favorable conditions for gene exchange. Conversely, dilute, oxygen-rich environments like surface waters tend to have lower HGT rates.
Reference
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