Excavation of Biomarker Candidates for the Diagnosis of Talaromyces marneffei Infection via Genome-Wide Prediction and Functional Annotation of Secreted Proteins.

Abstract

Talaromyces marneffei is the third most common infectious pathogen in AIDS patients and leads to the highest death rate in Guangxi, China. The lack of reliable biomarkers is one of the major obstacles in current clinical diagnosis, which largely contributes to this high mortality. Here, we present a study that aimed at identifying diagnostic biomarker candidates through genome-wide prediction and functional annotation of Talaromyces marneffei secreted proteins. A total of 584 secreted proteins then emerged, including 382 classical and 202 nonclassical ones. Among them, there were 87 newly obtained functional annotations in this study. The annotated proteins were further evaluated by combining RNA profiling and a homology comparison. Three proteins were ultimately highlighted as biomarker candidates with robust expression and remarkable specificity. The predicted phosphoinositide phospholipase C and the galactomannoprotein were suggested to play an interactive immune game through metabolism of arachidonic acid. Therefore, they hold promise in developing new tools for clinical diagnosis of Talaromyces marneffei and also possibly serve as molecular targets for future therapy.