Affiliation:
1. Department of Materials Science & Engineering Cornell University Ithaca New York USA
2. Department of Pathology & Immunology Baylor College of Medicine Houston Texas USA
3. Department of Pathology Texas Children's Hospital Houston Texas USA
4. Department of Regenerative Medicine & Cell Biology Medical University of South Carolina Charleston South Carolina USA
5. Department of Biology & Biochemistry University of Houston Houston Texas USA
6. Department of Mathematics University of Houston Houston Texas USA
7. Department of Microbiology & Immunology Medical University of South Carolina Charleston South Carolina USA
Abstract
AbstractArginine‐ornithine metabolism plays a crucial role in bacterial homeostasis, as evidenced by numerous studies. However, the utilization of arginine and the downstream products of its metabolism remain undefined in various gut bacteria. To bridge this knowledge gap, we employed genomic screening to pinpoint relevant metabolic targets. We also devised a targeted liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) metabolomics method to measure the levels of arginine, its upstream precursors, and downstream products in cell‐free conditioned media from enteric pathobionts, including Escherichia coli, Klebsiella aerogenes, K. pneumoniae, Pseudomonas fluorescens, Acinetobacter baumannii, Streptococcus agalactiae, Staphylococcus epidermidis, S. aureus, and Enterococcus faecalis. Our findings revealed that all selected bacterial strains consumed glutamine, glutamate, and arginine, and produced citrulline, ornithine, and GABA in our chemically defined medium. Additionally, E. coli, K. pneumoniae, K. aerogenes, and P. fluorescens were found to convert arginine to agmatine and produce putrescine. Interestingly, arginine supplementation promoted biofilm formation in K. pneumoniae, while ornithine supplementation enhanced biofilm formation in S. epidermidis. These findings offer a comprehensive insight into arginine‐ornithine metabolism in enteric pathobionts.