Please use this identifier to cite or link to this item: doi:10.22028/D291-39223
Volltext verfügbar? / Dokumentlieferung
Title: NamZ1 and NamZ2 from the Oral Pathogen Tannerella forsythia Are Peptidoglycan Processing Exo-β-N-Acetylmuramidases with Distinct Substrate Specificities
Author(s): Borisova, Marina
Balbuchta, Katja
Lovering, Andrew
Titz, Alexander
Mayer, Christoph
Language: English
Title: Journal of Bacteriology
Volume: 204
Issue: 3
Publisher/Platform: American Society for Microbiology
Year of Publication: 2022
Free key words: N-acetylmuramic acid (MurNAc)
MurNAc auxotrophy
peptidoglycan salvage
cell wall recycling
exo-lytic muramidase
CAZy glycosidase
family GH171
glycoside hydrolase
carbohydrate metabolism
DDC notations: 500 Science
Publikation type: Journal Article
Abstract: The Gram-negative periodontal pathogen Tannerella forsythia is inherently auxotrophic for N-acetylmuramic acid (MurNAc), which is an essential carbohydrate constituent of the peptidoglycan (PGN) of the bacterial cell wall. Thus, to build up its cell wall, T. forsythia strictly depends on the salvage of exogenous MurNAc or sources of MurNAc, such as polymeric or fragmentary PGN, derived from cohabiting bacteria within the oral microbiome. In our effort to elucidate how T. forsythia satisfies its demand for MurNAc, we recognized that the organism possesses three putative orthologs of the exo-b-N-acetylmuramidase BsNamZ from Bacillus subtilis, which cleaves nonreducing end, terminal MurNAc entities from the artificial substrate pNP-MurNAc and the naturally-occurring disaccharide substrate MurNAc-N-acetylglucosamine (MurNAc-GlcNAc). TfNamZ1 and TfNamZ2 were successfully purified as soluble, pure recombinant His6-fusions and characterized as exo-lytic b-N-acetylmuramidases with distinct substrate specificities. The activity of TfNamZ1 was considerably lower compared to TfNamZ2 and BsNamZ, in the cleavage of MurNAc-GlcNAc. When peptide-free PGN glycans were used as substrates, we revealed striking differences in the specificity and mode of action of these enzymes, as analyzed by mass spectrometry. TfNamZ1, but not TfNamZ2 or BsNamZ, released GlcNAc-MurNAc disaccharides from these glycans. In addition, glucosamine (GlcN)-MurNAc disaccharides were generated when partially N-deacetylated PGN glycans from B. subtilis 168 were applied. This characterizes TfNamZ1 as a unique disaccharide-forming exo-lytic b-N-acetylmuramidase (exo-disaccharidase), and, TfNamZ2 and BsNamZ as sole MurNAc monosaccharide-lytic exo-b-N-acetylmuramidases.
DOI of the first publication: 10.1128/jb.00597-21
URL of the first publication:
Link to this record: urn:nbn:de:bsz:291--ds-392237
ISSN: 1098-5530
Date of registration: 6-Mar-2023
Description of the related object: Supplemental Material
Related object:
Faculty: NT - Naturwissenschaftlich- Technische Fakultät
Department: NT - Chemie
Professorship: NT - Univ.-Prof. Dr. phil. Alexander Titz
Collections:SciDok - Der Wissenschaftsserver der Universität des Saarlandes

Files for this record:
There are no files associated with this item.

Items in SciDok are protected by copyright, with all rights reserved, unless otherwise indicated.