title: Small-molecule inhibition of choline catabolism in Pseudomonas aeruginosa and other aerobic choline-catabolizing bacteria.
abstract: Choline is abundant in association with eukaryotes and plays roles in osmoprotection, thermoprotection, and membrane biosynthesis in many bacteria. Aerobic catabolism of choline is widespread among soil proteobacteria, particularly those associated with eukaryotes. Catabolism of choline as a carbon, nitrogen, and/or energy source may play important roles in association with eukaryotes, including pathogenesis, symbioses, and nutrient cycling. We sought to generate choline analogues to study bacterial choline catabolism in vitro and in situ. Here we report the characterization of a choline analogue, propargylcholine, which inhibits choline catabolism at the level of Dgc enzyme-catalyzed dimethylglycine demethylation in Pseudomonas aeruginosa. We used genetic analyses and 13C nuclear magnetic resonance to demonstrate that propargylcholine is catabolized to its inhibitory form, propargylmethylglycine. Chemically synthesized propargylmethylglycine was also an inhibitor of growth on choline. Bioinformatic analysis suggests that there are genes encoding DgcA homologues in a variety of proteobacteria. We examined the broader utility of propargylcholine and propargylmethylglycine by assessing growth of other members of the proteobacteria that are known to grow on choline and possess putative DgcA homologues. Propargylcholine showed utility as a growth inhibitor in P. aeruginosa but did not inhibit growth in other proteobacteria tested. In contrast, propargylmethylglycine was able to inhibit choline-dependent growth in all tested proteobacteria, including Pseudomonas mendocina, Pseudomonas fluorescens, Pseudomonas putida, Burkholderia cepacia, Burkholderia ambifaria, and Sinorhizobium meliloti. We predict that chemical inhibitors of choline catabolism will be useful for studying this pathway in clinical and environmental isolates and could be a useful tool to study proteobacterial choline catabolism in situ.
authors: Department of Microbiology and Molecular Genetics, University of Vermont College of Medicine, 95 Carrigan Drive, 322 Stafford Hall, Burlington, VT 05405, USA.
authors: Liam F
authors: LF
authors: Fitzsimmons
authors: Stevenson
authors: S
authors: Flemer
authors: A Sandy
authors: AS
authors: Wurthmann
authors: P Bruce
authors: PB
authors: Deker
authors: Indra Neil
authors: IN
authors: Sarkar
authors: Matthew J
authors: MJ
authors: Wargo
references: Biochemistry. 1996 Apr 23;35(16):5292-9
references: 8611516
references: Mol Microbiol. 2010 Oct;78(1):13-34
references: 20923416
references: Methods Enzymol. 2007;428:77-107
references: 17875413
references: Plant Physiol. 1994 Nov;106(3):1187-1193
references: 12232402
references: Pediatr Pulmonol. 2007 Jun;42(6):533-41
references: 17469154
references: Can J Microbiol. 1977 May;23(5):483-90
references: 871964
references: Nucleic Acids Res. 2004 Mar 19;32(5):1792-7
references: 15034147
references: J Biol Chem. 1995 Jul 14;270(28):16701-13
references: 7622480
references: Biotechniques. 1993 Nov;15(5):831-4
references: 8267974
references: J Appl Physiol (1985). 1993 Oct;75(4):1661-9
references: 8282618
references: J Bacteriol. 2000 Jul;182(13):3843-5
references: 10851003
references: Eur J Biochem. 2001 Jun;268(12):3390-8
references: 11422368
references: J Biochem. 1977 Dec;82(6):1741-9
references: 599154
references: Curr Microbiol. 2001 Aug;43(2):107-11
references: 11391473
references: J Bacteriol. 1986 Mar;165(3):849-55
references: 3512525
references: Biochim Biophys Acta. 1977 Jul 14;468(2):209-26
references: 406917
references: Proc Natl Acad Sci U S A. 2009 Sep 8;106(36):15332-7
references: 19706413
references: Annu Rev Microbiol. 1991;45:569-606
references: 1741624
references: Microbiology (Reading). 2009 Jul;155(Pt 7):2411-2419
references: 19406895
references: Science. 1995 Jun 30;268(5219):1899-902
references: 7604262
references: Science. 1984 Jun 8;224(4653):1064-8
references: 16827211
references: J Med Chem. 2004 Mar 25;47(7):1767-74
references: 15027868
references: Biochemistry. 1999 Apr 27;38(17):5588-95
references: 10220347
references: J Bacteriol. 2008 Apr;190(8):2690-9
references: 17951379
references: J Bacteriol. 2006 Oct;188(20):7195-204
references: 17015658
references: J Bacteriol. 2011 Jun;193(12):3033-41
references: 21478341
references: J Mol Biol. 2006 Mar 24;357(2):592-606
references: 16445940
references: Microbiology (Reading). 2006 May;152(Pt 5):1395-1406
references: 16622056
references: Mol Microbiol. 2010 Jan;75(1):29-45
references: 19919675
references: Arch Mikrobiol. 1970;71(3):235-44
references: 4918912
references: J Microbiol Methods. 2006 Mar;64(3):391-7
references: 15987659
references: J Bacteriol. 1987 Oct;169(10):4597-601
references: 2820937
references: Mol Microbiol. 1997 Jan;23(1):43-56
references: 9004219
references: Bioinformatics. 2003 Aug 12;19(12):1572-4
references: 12912839
references: J Bacteriol. 2008 Apr;190(8):2717-25
references: 18156257
references: J Bacteriol. 1994 Sep;176(17):5364-71
references: 8071213
references: Mol Microbiol. 1992 Apr;6(7):863-71
references: 1602966
references: Appl Environ Microbiol. 2006 Jul;72(7):5027-36
references: 16820502
references: J Nutr Biochem. 1990 Jul;1(7):332-49
references: 15539223
references: Infect Immun. 2009 Mar;77(3):1103-11
references: 19103776
references: J Biol Chem. 1995 Aug 4;270(31):18252-9
references: 7543100
references: J Biol Chem. 1972 Sep 25;247(18):6004-6
references: 5057095
references: J Bacteriol. 1974 Sep;119(3):736-47
references: 4604283
references: Appl Environ Microbiol. 1999 May;65(5):2072-7
references: 10224003