ChipFilter: Microfluidic-Based Comprehensive Sample Preparation Methodology for Microbial Consortia

Area of Science:

• Microbiology
• Proteomics
• Analytical Chemistry

Background:

• Metaproteomics offers functional insights into microbiomes but faces challenges in protein extraction from complex samples.
• Current methods struggle with low cell densities and heterogeneous microbial communities.

Purpose of the Study:

• To evaluate a ChipFilter microfluidic device for direct microbial cell lysis and protein digestion in metaproteomic workflows.
• To assess the efficiency of the ChipFilter coupled with LC-MS/MS for identifying microbial proteins.

Main Methods:

• Utilized a ChipFilter microfluidic device for direct cell lysis and in-situ protein digestion.
• Employed liquid chromatography tandem mass spectrometry (LC-MS/MS) for peptide identification and quantification.
• Tested the system with pure cultures (E. coli, B. subtilis, S. cerevisiae) and a complex 17-species gut microbiome mixture.

Main Results:

• The ChipFilter system successfully identified microbial proteins directly from lysed cells.
• Higher numbers of proteins and peptides were identified compared to standard protocols, particularly at low cell densities.
• The ChipFilter preparation identified and quantified 16 out of 17 species in a complex gut microbiome sample.

Conclusions:

• The ChipFilter microfluidic device is an effective tool for metaproteomic analysis of microbiomes.
• This approach overcomes technical challenges in protein extraction, especially for low-volume or low-cell-density samples.
• The method facilitates improved functional characterization of microbial communities.