A Split Methyl Halide Transferase AND Gate That Reports by Synthesizing an Indicator Gas

Area of Science:

• Biotechnology
• Microbiology
• Molecular Biology

Background:

• Monitoring microbial post-translational modifications in complex environments like soil and seawater is difficult.
• Existing methods struggle with opaque or autofluorescent sample matrices.

Purpose of the Study:

• To develop a simple, gas-reporting assay for observing microbial post-translational reactions in environmental samples.
• To create a novel genetic AND gate for detecting protein-protein interactions.

Main Methods:

• Designed a split methyl halide transferase (sMHT) fragment complementation assay.
• Engineered sMHT AND gates that synthesize the indicator gas methyl bromide (CH3Br) upon fragment association.
• Fused sMHT fragments to interacting proteins (FKBP12 and mTOR domains) to enhance gas production.

Main Results:

• Demonstrated that split MHT fragments can form functional AND gates producing CH3Br.
• Showed that sMHT activity is enhanced when fragments are fused to interacting partner proteins.
• Confirmed the reversibility of the assay using a competitive inhibitor, indicating dynamic monitoring capabilities.

Conclusions:

• The sMHT assay provides a novel method for detecting microbial post-translational reactions and protein-protein interactions via indicator gas production.
• This assay is suitable for hard-to-image environmental matrices, offering a new tool for microbial ecology and biotechnology.