The acceleration of the process of understanding the pharmacological application of new marine bioactive compounds requires identifying the compound
protein targets leading the molecular mechanisms in a living cell. The thermal
proteome profiling (TPP) methodology does not fulfill the requirements for its application to any bioactive compound lacking chemical and functional characterization. Here, we present a modified method that we called
bTPP for bioactive thermal
proteome profiling that guarantees target specificity from a soluble subproteome. We showed that the precipitation of the microsomal fraction before the thermal shift assay is crucial to accurately calculate the melting points of the
protein targets. As a probe of concept, the
protein targets of 132-hydroxy-pheophytin, a compound previously isolated from a marine cyanobacteria for its
lipid reducing activity, were analyzed on the hepatic cell line HepG2. Our improved method identified 9
protein targets out of 2500
proteins, including 3 targets (
isocitrate dehydrogenase,
aldehyde dehydrogenase,
phosphoserine aminotransferase) that could be related to
obesity and diabetes, as they are involved in the regulation of
insulin sensitivity and energy metabolism. This study demonstrated that the
bTPP method can accelerate the field of biodiscovery, revealing
protein targets involved in mechanisms of action (MOA) connected with future applications of bioactive compounds.