Proteotyping as alternate typing method to differentiate Campylobacter coli clades

Area of Science:

• Microbiology
• Bacteriology
• Proteomics

Background:

• Campylobacter coli is a leading bacterial cause of gastroenteritis globally.
• C. coli isolates are classified into three clades based on sample source, with Clade 1 linked to human infections and Clades 2/3 to environmental sources.
• Phylogenetic classification typically relies on laborious multilocus sequence typing (MLST).

Purpose of the Study:

• To develop a proteotyping scheme utilizing MALDI-TOF MS as a rapid alternative to sequence-based methods for C. coli classification.
• To establish a reliable method for differentiating C. coli clades and sub-clades.

Main Methods:

• Analysis of 97 clade-representative C. coli isolates using MALDI-TOF-based intact cell mass spectrometry (ICMS).
• Utilized MLST as the reference method for phylogenetic classification.
• Identified and incorporated proteomic biomarkers, including isoforms with mass shifts, into the proteotyping scheme.

Main Results:

• Successfully established a C. coli proteotyping scheme based on MALDI-TOF MS.
• Identified 16 biomarkers capable of differentiating C. coli into its three main clades.
• Further resolved three additional sub-clades within the clinically significant Clade 1.

Conclusions:

• Proteotyping is a viable and effective method for classifying C. coli isolates.
• The developed MALDI-TOF MS proteotyping scheme accurately discriminates between C. coli clades and sub-clades.
• This approach offers a significant improvement in speed and efficiency for the classification of clinically relevant C. coli.