MHBMDAA: Membrane-based DNA array with high resolution and sensitivity for toxic microalgae monitoring

Area of Science:

• Marine Biology
• Environmental Science
• Molecular Diagnostics

Background:

• Harmful algal blooms (HABs) caused by toxic microalgae pose significant threats to marine ecosystems and industries.
• Effective monitoring techniques are crucial for early warning of HAB events.
• Existing methods may lack the sensitivity or efficiency required for timely detection.

Purpose of the Study:

• To develop a sensitive and reliable method for detecting toxic microalgae.
• To create a DNA array assay for early warning of harmful algal blooms.
• To improve upon existing detection techniques for marine toxins.

Main Methods:

• Sequencing of partial large subunit rDNA (D1-D2) from eight toxic microalgae species.
• Design of specific padlock probes (PLP) and taxonomic probes.
• Development of a multiplex hyperbranched rolling circle amplification (MHRCA) technique.
• Hybridization of amplified products to a membrane DNA array, creating the MHRCA-based membrane DNA array assay (MHBMDAA).

Main Results:

• The MHBMDAA demonstrated high specificity through cross-reactivity tests.
• The assay detected simulated samples at concentrations from 10^3 to 10^-1 cells mL^-1.
• MHBMDAA showed 10-fold greater sensitivity compared to multiplex PCR-based membrane DNA arrays.
• Validation with natural samples from the East China Sea confirmed assay effectiveness.

Conclusions:

• The developed MHBMDAA is a valuable tool for the sensitive and reliable detection of toxic microalgae.
• This assay provides an effective means for early warning of harmful algal blooms.
• The MHBMDAA supports ongoing research into marine toxins and harmful algal bloom dynamics.