Authors:	Schubert, Christopher Winter, Maria Ebert-Jung, Andrea Kierszniowska, Sylwia Nagel-Wolfrum, Kerstin Schramm, Thorben Link, Hannes Winter, Sebastian Unden, Gottfried
Title:	C4-dicarboxylates and L-aspartate utilization by Escherichia coli K-12 in the mouse intestine : L-aspartate as a major substrate for fumarate respiration and as a nitrogen source
Online publication date:	15-Nov-2022
Year of first publication:	2021
Language:	english
Abstract:	C4-dicarboxylates, such as fumarate, l-malate and l-aspartate represent substrates for anaerobic growth of Escherichia coli by fumarate respiration. Here, we determined whether C4-dicarboxylate metabolism, as well as fumarate respiration, contribute to colonization of the mammalian intestinal tract. Metabolite profiling revealed that the murine small intestine contained high and low levels of l-aspartate and l-malate respectively, whereas fumarate was nearly absent. Under laboratory conditions, addition of C4-dicarboxylate at concentrations corresponding to the levels of the C4-dicarboxylates in the small intestine (2.6 mmol kg−1 dry weight) induced the dcuBp-lacZ reporter gene (67% of maximal) in a DcuS-DcuR-dependent manner. In addition to its role as a precursor for fumarate respiration, l-aspartate was able to supply all the nitrogen required for anaerobically growing E. coli. DcuS-DcuR-dependent genes were transcribed in the murine intestine, and mutants with defective anaerobic C4-dicarboxylate metabolism (dcuSR, frdA, dcuB, dcuA and aspA genes) were impaired for colonizing the murine gut. We conclude that l-aspartate plays an important role in providing fumarate for fumarate respiration and supplying nitrogen for E. coli in the mouse intestine.
DDC:	570 Biowissenschaften 570 Life sciences
Institution:	Johannes Gutenberg-Universität Mainz
Department:	FB 10 Biologie
Place:	Mainz
ROR:	https://ror.org/023b0x485
DOI:	http://doi.org/10.25358/openscience-8147
Version:	Published version
Publication type:	Zeitschriftenaufsatz
License:	CC BY
Information on rights of use:	https://creativecommons.org/licenses/by/4.0/
Journal:	Environmental microbiology 23 5
Pages or article number:	2564 2577
Publisher:	Wiley-Blackwell
Publisher place:	Oxford u.a.
Issue date:	2021
ISSN:	1462-2920
Publisher DOI:	10.1111/1462-2920.15478
Appears in collections:	JGU-Publikationen