High-Throughput Identification of Crystalline Natural Products from Crude Extracts Enabled by Microarray Technology...

Area of Science:

• Natural Product Discovery
• Structural Biology
• Analytical Chemistry

Background:

• Structural determination of natural products (NPs) is challenging due to sample heterogeneity and limited quantities.
• Microcrystal electron diffraction (microED) shows potential but faces limitations in throughput and purity requirements.
• Existing methods like mass spectrometry (MS) and UV/vis spectroscopy may miss certain chemical species or crystal forms.

Purpose of the Study:

• To develop a high-throughput screening platform for natural product structural determination.
• To overcome limitations of traditional NP discovery workflows and microED implementation.
• To enable rapid identification and structural characterization of crystalline metabolites from crude extracts.

Main Methods:

• Leveraged transmission electron microscopy (TEM) and DNA microarray technology to create an NP screening platform: array electron diffraction (ArrayED).
• Deposited high-performance liquid chromatography (HPLC) fractions from crude extracts onto TEM grids in picoliter droplets for multiplexed analysis.
• Utilized selected area electron diffraction analysis on microarrayed grids for rapid identification of crystalline metabolites.

Main Results:

• ArrayED enabled structural characterization of 14 natural products from 20 crude extracts.
• Identified four novel crystal structures and two novel polymorphs.
• Detected chemical species and crystal forms undetectable by standard MS, UV/vis, or traditional methods.

Conclusions:

• ArrayED is an effective platform for accelerating natural product discovery and structural elucidation.
• The method significantly enhances throughput and sample utilization in electron diffraction studies.
• ArrayED expands the scope of detectable compounds and crystal forms in natural product research.