Eggerthella lenta is a prevalent human gut Actinobacterium implicated in drug, dietary phytochemical, and bile acid metabolism and associated with multiple human diseases. No genetic tools are currently available for the direct manipulation of E. lenta. Here, we construct shuttle vectors and develop methods to transform E. lenta and other Coriobacteriia. With these tools, we characterize endogenous E. lenta constitutive and inducible promoters using a reporter system and construct inducible expression systems, enabling tunable gene regulation. We also achieve genome editing by harnessing an endogenous type I-C CRISPR-Cas system. Using these tools to perform genetic knockout and complementation, we dissect the functions of regulatory proteins and enzymes involved in catechol metabolism, revealing a previously unappreciated family of membrane-spanning LuxR-type transcriptional regulators. Finally, we employ our genetic toolbox to study the effects of E. lenta genes on mammalian host biology. By greatly expanding our ability to study and engineer gut Coriobacteriia, these tools will reveal mechanistic details of host-microbe interactions and provide a roadmap for genetic manipulation of other understudied human gut bacteria.

Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae). Although initially it was thought that testosterone inhibited the display of paternal behavior in males of rodents, it has been shown that in some species high testosterone levels are needed for exhibition of paternal care. In captivity, males of volcano Mouse (Neotomodon alstoni) provide pups the same care provided by the mother, with the exception of suckling. Here we measured plasmatic testosterone concentrations 10 days after mating, five and 20 days postpartum, and 10 days after males were isolated from their families in order to determine possible changes in this hormone, associated to the presence and age of pups. Males of volcano Mouse exhibited paternal behavior when their testosterone levels were relatively high. Although levels of this hormone did not change with the presence or pups age, males that invested more time in huddling showed higher testosterone levels. It is possible that in the volcano Mouse testosterone modulates paternal behavior indirectly, as in the California mouse.

The purpose of this study was to evaluate the effect of cyproterone acetate (CPA, A) compared with new synthetic steroids 3alpha-acetoxy-5,6-epoxy-16-pregnen-20-one (B) and 17alpha-hydroxy-16beta-methyl-1,4,6-pregnatriene-3,20-dione (C) in rat prostate and brain. Groups of animals were treated either with A, B or C (4 mg kg(-1) day(-1)) by the intraperitoneal route for 5 days. Levels of reduced glutathione (GSH), 5-hydroxy-indole acetic acid (5-HIAA), lipid peroxidation (as thiobarbituric acid reactive substances, TBARS) and the activities of Na(+), K(+)- and total ATPases were assayed in prostate and brain for each group of animals including a control group. No appreciable changes were shown in Na(+), K(+)-ATPase and total ATPases and TBARS on prostate and brain of rats that received A, B and C steroids. However, the levels of GSH and 5-HIAA decreased significantly (P < 0.05) in both tissues for the steroids assayed. It is concluded that CPA and the homologues B and C steroids induce changes in the levels of GSH and serotonin in rat prostate and brain.

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