Sialic Acid ( N -Acetyl Neuraminic Acid) Utilization by Bacteroides fragilis Requires a Novel N -Acetyl Mannosamine Epimerase
- 1 June 2009
- journal article
- Published by American Society for Microbiology in Journal of Bacteriology
- Vol. 191 (11), 3629-3638
- https://doi.org/10.1128/jb.00811-08
Abstract
We characterized the nanLET operon in Bacteroides fragilis , whose products are required for the utilization of the sialic acid N- acetyl neuraminic acid (NANA) as a carbon and energy source. The first gene of the operon is nanL , which codes for an aldolase that cleaves NANA into N -acetyl mannosamine (manNAc) and pyruvate. The next gene, nanE , codes for a manNAc/ N -acetylglucosamine (NAG) epimerase, which, intriguingly, possesses more similarity to eukaryotic renin binding proteins than to other bacterial NanE epimerase proteins. Unphosphorylated manNAc is the substrate of NanE, while ATP is a cofactor in the epimerase reaction. The third gene of the operon is nanT , which shows similarity to the major transporter facilitator superfamily and is most likely to be a NANA transporter. Deletion of any of these genes eliminates the ability of B. fragilis to grow on NANA. Although B. fragilis does not normally grow with manNAc as the sole carbon source, we isolated a B. fragilis mutant strain that can grow on this substrate, likely due to a mutation in a NAG transporter; both manNAc transport and NAG transport are affected in this strain. Deletion of the nanE epimerase gene or the rokA hexokinase gene, whose product phosphorylates NAG, in the manNAc-enabled strain abolishes growth on manNAc. Thus, B. fragilis possesses a new pathway of NANA utilization, which we show is also found in other Bacteroides species.Keywords
This publication has 32 references indexed in Scilit:
- Evolution of Symbiotic Bacteria in the Distal Human IntestinePLoS Biology, 2007
- Novel Sialic Acid Transporter of Haemophilus influenzaeInfection and Immunity, 2005
- Prokaryotic origin of cytidylyltransferases and α-ketoacid synthasesTrends in Microbiology, 2004
- Cloning of the Tannerella forsythensis (Bacteroides forsythus) siaHI gene and purification of the sialidase enzymeJournal of Medical Microbiology, 2003
- Evidence of Regio-specific Glycosylation in Human Intestinal MucinsPublished by Elsevier BV ,2003
- Chemical Diversity in the Sialic Acids and Related α-Keto Acids: An Evolutionary PerspectiveChemical Reviews, 2002
- Crystal structure of N-acyl-d-glucosamine 2-epimerase from porcine kidney at 2.0 Å resolutionJournal of Molecular Biology, 2000
- Isolation of Bacteroides fragilis Mutants with In Vivo Growth Defects by Using Tn 4400 ′, a Modified Tn 4400 Transposition System, and a New Screening MethodInfection and Immunity, 2000
- Properties of Renin-Binding ProteinClinical and Experimental Hypertension. Part A: Theory and Practice, 1982
- Preparation of N-Acetyl-D-mannosamine (2-Acetamido-2-deoxy-D-mannose) and D-Mannosamine Hydrochloride (2-Amino-2-deoxy-D-mannose)1Journal of the American Chemical Society, 1959