Clostridioides difficile para-Cresol Production Is Induced by the Precursor para-Hydroxyphenylacetate

Autor: Lisa F. Dawson, Mark Harrison, Harparkash Kaur, Isabelle Martin-Verstraete, Alexandra Faulds-Pain, Bruno Dupuy, Adriano O. Henriques, Brendan W. Wren
Přispěvatelé: London School of Hygiene and Tropical Medicine (LSHTM), Pathogénèse des Bactéries Anaérobies / Pathogenesis of Bacterial Anaerobes (PBA (U-Pasteur_6)), Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Instituto de Tecnologia Química e Biológica António Xavier (ITQB), Universidade Nova de Lisboa = NOVA University Lisbon (NOVA), Université Paris Diderot, Sorbonne Paris Cité, Paris, France, Université Paris Diderot - Paris 7 (UPD7), This study was supported by the Medical Research Council (LSHTM studentship MR/N013638/1). Funding for B.W.W. and A.F.-P. was provided Medical Research Council grant MR/K000551/1. Funding for L.F.D. was provided by an ISSF Fellowship from the Wellcome Trust (105609/Z/14/Z) and an Athena Swan Career Restart Fellowship (from London School of Hygiene and Tropical Medicine)., We thank Shonna McBride for providing pMC358 for use in the study., Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Journal of Bacteriology
Journal of Bacteriology, American Society for Microbiology, 2020, 202 (18), pp.e00282-20. ⟨10.1128/JB.00282-20⟩
Journal of Bacteriology, 2020, 202 (18), pp.e00282-20. ⟨10.1128/JB.00282-20⟩
ISSN: 0021-9193
1098-5530
DOI: 10.1128/JB.00282-20⟩
Popis: Clostridioides difficile infection results from antibiotic-associated dysbiosis. para-Cresol, a phenolic compound produced by C. difficile, selectively targets gammaproteobacteria in the gut, facilitating dysbiosis. Here, we demonstrate that expression of the hpdBCA operon, encoding the HpdBCA decarboxylase which converts p-HPA to p-cresol, is upregulated in response to elevated exogenous p-HPA, with induction occurring between >0.1 and ≤0.25 mg/ml. We determined a single promoter and an inverted palindromic repeat responsible for basal and p-HPA-inducible hpdBCA expression. We identified turnover of tyrosine, a p-HPA precursor, does not induce hpdBCA expression above basal level, indicating that exogenous p-HPA was required for p-cresol production. Identifying regulatory controls of p-cresol production will provide novel therapeutic targets to prevent p-cresol production, reducing C. difficile’s competitive advantage.
Clostridioides difficile is an etiological agent for antibiotic-associated diarrheal disease. C. difficile produces a phenolic compound, para-cresol, which selectively targets gammaproteobacteria in the gut, facilitating dysbiosis. C. difficile decarboxylates para-hydroxyphenylacetate (p-HPA) to produce p-cresol by the action of the HpdBCA decarboxylase encoded by the hpdBCA operon. Here, we investigate regulation of the hpdBCA operon and directly compare three independent reporter systems; SNAP-tag, glucuronidase gusA, and alkaline phosphatase phoZ reporters to detect basal and inducible expression. We show that expression of hpdBCA is upregulated in response to elevated p-HPA. In silico analysis identified three putative promoters upstream of hpdBCA operon—P1, P2, and Pσ54; only the P1 promoter was responsible for both basal and p-HPA-inducible expression of hpdBCA. We demonstrated that turnover of tyrosine, a precursor for p-HPA, is insufficient to induce expression of the hpdBCA operon above basal levels because it is inefficiently converted to p-HPA in minimal media. We show that induction of the hpdBCA operon in response to p-HPA occurs in a dose-dependent manner. We also identified an inverted palindromic repeat (AAAAAG-N13-CTTTTT) upstream of the hpdBCA start codon (ATG) that is essential for inducing transcription of the hpdBCA operon in response to p-HPA, which drives the production of p-cresol. This provides insights into the regulatory control of p-cresol production, which affords a competitive advantage for C. difficile over other intestinal bacteria, promoting dysbiosis. IMPORTANCE Clostridioides difficile infection results from antibiotic-associated dysbiosis. para-Cresol, a phenolic compound produced by C. difficile, selectively targets gammaproteobacteria in the gut, facilitating dysbiosis. Here, we demonstrate that expression of the hpdBCA operon, encoding the HpdBCA decarboxylase which converts p-HPA to p-cresol, is upregulated in response to elevated exogenous p-HPA, with induction occurring between >0.1 and ≤0.25 mg/ml. We determined a single promoter and an inverted palindromic repeat responsible for basal and p-HPA-inducible hpdBCA expression. We identified turnover of tyrosine, a p-HPA precursor, does not induce hpdBCA expression above basal level, indicating that exogenous p-HPA was required for p-cresol production. Identifying regulatory controls of p-cresol production will provide novel therapeutic targets to prevent p-cresol production, reducing C. difficile’s competitive advantage.
Databáze: OpenAIRE
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