Table 3 Microbial enzymes contributing to the testobolome and their functional roles in androgen metabolism

3α-HSD

Lachnolostridium scindens¹⁴⁸,

Eggerthella lenta^149,150,151,

Arthrobacter koreensis¹⁰⁷,

Parabacteroides distasonis¹⁵¹,

Raoultibacter timonensis¹⁵¹,

Gordonibacter pamelaeae¹⁵¹,

Clostridium perfringens¹⁵³,

Comamonas testosteroni¹⁴⁸,

Streptomyces hydrogenans¹⁵²

↓ androgen potency;

weak ERβ activation (via androstanediol)

3β-HSD

Pseudomonas nitroreducens⁸⁵,

Eggerthella lenta^149,151,

Gordonibacter pamelaeae¹⁵¹,

Ruminococcus gnavus¹⁵⁰,

Clostridium innocuum⁷⁵,

Clostridium perfringens¹⁵³,

Klebsiella aerogenes¹⁵⁴,

Parabacteroides merdae¹⁵¹,

Odoribacter laneus¹⁵¹,

Odoribacteraceae spp¹⁵¹,

Mycobacterium leprae¹⁵⁵,

Comamonas testosteroni^71,156

↓ androgen potency;

potential ERβ activation (via androstanediol)

17β-HSD

Pseudomonas nitroreducens⁸⁵,

Comamonas testosteroni^71,156,

Rhodococcus sp P14¹⁵⁷,

Lysinibacillus sphaericus DH-B01¹⁵⁸,

Pseudomonas putida SJTE-1¹⁵⁹

Interconversion between active (17β-hydroxy) and inactive (17-keto) androgens/estrogens; can either increase or decrease potency depending on direction

5β-reductase

Lachnolostridium scindens¹⁶¹,

Clostridium innocuum⁷⁵,

Clostridium hylemonae¹⁵¹, Bacteroides and Parabacteroides strains ¹⁵¹,

Androgen inactivation;

enhanced clearance (via 5β-androstanes)

5α-reductase

Parabacteroides merdae¹⁵¹,

Odoribacter laneus¹⁵¹,

Odoribacteraceae spp¹⁵¹,

Bacteroides dorei¹⁵¹,

Alistipes sp¹⁵¹,

Bacteroides and Parabacteroides strains¹⁵¹

Bacteroidetes bacteria¹⁶⁰,

Proteobacteria bacteria¹⁶⁰,

Deltaproteobacteria bacterium¹⁶⁰,

Spirochaetae bacterium HGW-Spirochaetae-1¹⁶⁰,

Saprospirales bacterium¹⁶⁰,

Chitinophaga niastensis¹⁶⁰,

Chitinophaga ginsengisegetis¹⁶⁰,

Chitinophaga arvensicola¹⁶⁰,

Chitinophaga sp GDMCC 1.1325¹⁶⁰,

Sandaracinus sp¹⁶⁰

↑ androgen potency (if DHT is produced)