SSTDhunter: a curated gene database for investigating androgen producing potential in microbiota species.

Steroid-17,20-desmolase (SSTD) in microbes is responsible for 11-oxy-androgen production via biotransformation from cortisol and other endogenous steroids and pharmaceutical glucocorticoids.

• SSTD activity has been well-characterized in Clostridium scindens ATCC 35704.
• SSTD is a complex formed by N-terminal and C-terminal transketolases encoded by desA and desB genes.
• The side-chain cleavage product of prednisone could significantly promote the proliferation of prostate cancer cells.

A professional database called SSTDhunter was constructed for rapid investigation of SSTD-coding genes in massive metagenomic data.

• SSTDhunter was built using large-scale genomic analysis along with homologous genes as background.
• SSTD-coding genes were reconstructed through comprehensive characteristics including operon structures, sequence identities, phylogenetic topologies, and comparative analysis.
• Protein sequences of homologous genes tktA, which encode components of sugar transketolase, were included as background noise to reduce false positives.
• SSTDhunter is freely available at http://www.orgene.net/SSTDhunter/.

A void existed in evaluating androgen-producing potential by gut microbiota due to relatively low abundance of SSTD-carrying species and lack of a professional gene database.

• Mining SSTD encoding genes in large sequencing datasets had become computationally expensive and time-consuming using comprehensive databases.
• The relatively low abundance of SSTD-carrying species in gut microbiota contributed to the gap in evaluation tools.
• SSTDhunter was developed specifically to address this gap for prostate cancer patients under Androgen Deprivation Therapy (ADT) such as castration treatment.

Androgens produced by gut microbes are critical in the context of prostate cancer, particularly for patients undergoing Androgen Deprivation Therapy.

• Androgens are critical for the growth of prostate cells as well as prostate tumor cells.
• For prostate cancer patients under ADT including castration treatment, investigating the potential for androgen production by gut microbes is crucial.
• The side-chain cleavage product of prednisone could significantly promote the proliferation of prostate cancer cells.