TY - JOUR
T1 - C4-dicarboxylates and l-aspartate utilization by Escherichia coli K-12 in the mouse intestine
T2 - l-aspartate as a major substrate for fumarate respiration and as a nitrogen source
AU - Schubert, Christopher
AU - Winter, Maria
AU - Ebert-Jung, Andrea
AU - Kierszniowska, Sylwia
AU - Nagel-Wolfrum, Kerstin
AU - Schramm, Thorben
AU - Link, Hannes
AU - Winter, Sebastian
AU - Unden, Gottfried
N1 - Publisher Copyright:
© 2021 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.
PY - 2021/5
Y1 - 2021/5
N2 - 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.
AB - 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.
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U2 - 10.1111/1462-2920.15478
DO - 10.1111/1462-2920.15478
M3 - Article
C2 - 33754467
AN - SCOPUS:85104262197
SN - 1462-2912
VL - 23
SP - 2564
EP - 2577
JO - Environmental Microbiology
JF - Environmental Microbiology
IS - 5
ER -