The New Omics Measuring Molecular Interactions

Protein and metabolite interaction is the latest “omics.” Swiss biochemists “extracted cellular fluid, which contains proteins, from the bacterial cells. They then added a metabolite to each sample and allowed it to interact with the proteins. Finally, they cut the proteins into smaller pieces (peptides) using “molecular scissors”. In total, the researchers tested 20 different metabolites and their interactions with proteins in this way. When a protein interacts with a metabolite, whether it settles in the protein’s active site or attaches to another site, the protein structure is altered. The “molecular scissors” then cut it at different sites from the original structure, resulting in a different set of peptides. Using the mass spectrometer, the researchers measured all of the pieces present in the sample and fed the data obtained into a computer to reconstruct the structural differences and changes, and where in the protein these are localised.” In this way, the researchers identified 1,400 protein-metabolite interactions that had not been explained before, indicating ways that these interactions alter function. MORE

Image Credit: Ilaria Piazza / ETH Zurich / PDB database entry 4MQT