An efficient and cost-effective method for DNA extraction from athalassohaline soil using a newly formulated cell...

Area of Science:

• Environmental microbiology
• Molecular biology
• Soil science

Background:

• Existing direct lysis methods for environmental DNA (eDNA) extraction from athalassohaline soils cause DNA shearing and co-extraction of extracellular DNA.
• Direct lysis is further complicated by salt precipitation during DNA purification, reducing yield.
• High-salt soils often have low microbial biomass, making efficient DNA extraction challenging.

Purpose of the Study:

• To develop a rapid and efficient indirect lysis method for eDNA extraction from athalassohaline soils.
• To optimize a novel cell extraction buffer for improved DNA yield and purity.
• To validate the new method against existing protocols for soil eDNA extraction.

Main Methods:

• An indirect lysis approach using a newly formulated cell extraction buffer was developed.
• Buffer composition and concentration, including polyethylene glycol (PEG) 8000 and NaCl, were optimized.
• Low and high-speed centrifugation steps were incorporated, and cell extraction efficiency was assessed using acridine orange staining.

Main Results:

• The optimized method achieved a high DNA yield (5.6 ± 0.7 μg g⁻¹) with superior purity.
• The new procedure demonstrated better efficiency and reproducibility compared to existing methods and commercial kits.
• Extracted DNA was suitable for downstream molecular applications, including PCR amplification of the 16S rRNA gene.

Conclusions:

• The developed indirect lysis method provides a robust and efficient means for extracting high-quality environmental DNA from challenging high-salt soil environments.
• This method overcomes limitations of direct lysis, improving the reliability of microbial community and functional analyses.
• The optimized cell extraction buffer and protocol are valuable for soil microbial ecology studies.