6U7I

Faecalibacterium prausnitzii Beta-glucuronidase

Summary for 6U7I

• Entry DOI: 10.2210/pdb6u7i/pdb
• Descriptor: Beta-glucuronidase (2 entities in total)
• Functional Keywords: microbiome, glycosyl hydrolase, hydrolase
• Biological source: Faecalibacterium prausnitzii
• Total number of polymer chains: 4
• Total formula weight: 268952.88

Authors

Ervin, S.M.,Redinbo, M.R. (deposition date: 2019-09-03, release date: 2019-10-30, Last modification date: 2023-10-11)

Primary citation

Ervin, S.M.,Li, H.,Lim, L.,Roberts, L.R.,Liang, X.,Mani, S.,Redinbo, M.R.
Gut microbial beta-glucuronidases reactivate estrogens as components of the estrobolome that reactivate estrogens.
J.Biol.Chem., 294:18586-18599, 2019

PubMed Abstract: Gut microbial β-glucuronidase (GUS) enzymes have been suggested to be involved in the estrobolome, the collection of microbial reactions involving estrogens. Furthermore, bacterial GUS enzymes within the gastrointestinal tract have been postulated to be a contributing factor in hormone-driven cancers. However, to date, there has been no experimental evidence to support these hypotheses. Here we provide the first analysis of the ability of 35 human gut microbial GUS enzymes to reactivate two distinct estrogen glucuronides, estrone-3-glucuronide and estradiol-17-glucuronide, to estrone and estradiol, respectively. We show that certain members within the Loop 1, mini-Loop 1, and FMN-binding classes of gut microbial GUS enzymes can reactivate estrogens from their inactive glucuronides. We provide molecular details of key interactions that facilitate these catalytic processes and present the structures of two novel human gut microbial GUS enzymes related to the estrobolome. Further, we demonstrate that estrogen reactivation by Loop 1 bacterial GUS enzymes can be inhibited both in purified enzymes and in fecal preparations of mixed murine fecal microbiota. Finally, however, despite these and data, we show that a Loop 1 GUS-specific inhibitor is not capable of reducing the development of tumors in the PyMT mouse model of breast cancer. These findings validate that gut microbial GUS enzymes participate in the estrobolome but also suggest that the estrobolome is a multidimensional set of processes on-going within the mammalian gastrointestinal tract that likely involves many enzymes, including several distinct types of GUS proteins.

PubMed: 31636122
DOI: 10.1074/jbc.RA119.010950

Experimental method

X-RAY DIFFRACTION (2.7 Å)