Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid

Abstract The nonulosonic acid 8-epipseudaminic acid was discovered only recently in two Acinetobacter baumannii strains but the genes responsible for conversion of pseudaminic acid to its 8-epimer were not found at the K locus. Here, we use a pan-genome approach to identify a pair of carbohydrate bi...

Full description

Saved in:
Bibliographic Details
Main Authors: Nowshin S. Sharar, Andrea Iovine, Cristina De Castro, Ruth M. Hall, Johanna J. Kenyon
Format: Article
Language:English
Published: Nature Portfolio 2025-05-01
Series:Communications Biology
Online Access:https://doi.org/10.1038/s42003-025-08114-8
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850277633645871104
author Nowshin S. Sharar
Andrea Iovine
Cristina De Castro
Ruth M. Hall
Johanna J. Kenyon
author_facet Nowshin S. Sharar
Andrea Iovine
Cristina De Castro
Ruth M. Hall
Johanna J. Kenyon
author_sort Nowshin S. Sharar
collection DOAJ
description Abstract The nonulosonic acid 8-epipseudaminic acid was discovered only recently in two Acinetobacter baumannii strains but the genes responsible for conversion of pseudaminic acid to its 8-epimer were not found at the K locus. Here, we use a pan-genome approach to identify a pair of carbohydrate biosynthesis genes, epaA and epaB, and demonstrate using NMR analysis of the capsular polysaccharide that they encode enzymes able to convert pseudaminic acid to its 8-epimer. Via an extensive survey of available A. baumannii genomes, we show that the epaA and epaB genes are present in 17 different Caudoviricetes class prophages. The prophages are in genomes that carry different capsule biosynthesis loci from isolates recovered in several different countries. The presence of epaA and epaB genes in A. baumannii isolates that are able to produce pseudaminic acid leads to modification of capsular polysaccharides that decorate their cell surface with potential implications for capsule typing and capsule-targeting therapies.
format Article
id doaj-art-eb921fbe3eb94610b03cc9a86d6c8ba3
institution OA Journals
issn 2399-3642
language English
publishDate 2025-05-01
publisher Nature Portfolio
record_format Article
series Communications Biology
spelling doaj-art-eb921fbe3eb94610b03cc9a86d6c8ba32025-08-20T01:49:48ZengNature PortfolioCommunications Biology2399-36422025-05-018111010.1038/s42003-025-08114-8Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acidNowshin S. Sharar0Andrea Iovine1Cristina De Castro2Ruth M. Hall3Johanna J. Kenyon4Centre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of TechnologyDepartment of Chemical Sciences, University of Napoli Federico II Complesso Universitario Monte Santangelo, Via Cintia 4Department of Chemical Sciences, University of Napoli Federico II Complesso Universitario Monte Santangelo, Via Cintia 4School of Life and Environmental Science, The University of SydneyCentre for Immunology and Infection Control, School of Biomedical Sciences, Faculty of Health, Queensland University of TechnologyAbstract The nonulosonic acid 8-epipseudaminic acid was discovered only recently in two Acinetobacter baumannii strains but the genes responsible for conversion of pseudaminic acid to its 8-epimer were not found at the K locus. Here, we use a pan-genome approach to identify a pair of carbohydrate biosynthesis genes, epaA and epaB, and demonstrate using NMR analysis of the capsular polysaccharide that they encode enzymes able to convert pseudaminic acid to its 8-epimer. Via an extensive survey of available A. baumannii genomes, we show that the epaA and epaB genes are present in 17 different Caudoviricetes class prophages. The prophages are in genomes that carry different capsule biosynthesis loci from isolates recovered in several different countries. The presence of epaA and epaB genes in A. baumannii isolates that are able to produce pseudaminic acid leads to modification of capsular polysaccharides that decorate their cell surface with potential implications for capsule typing and capsule-targeting therapies.https://doi.org/10.1038/s42003-025-08114-8
spellingShingle Nowshin S. Sharar
Andrea Iovine
Cristina De Castro
Ruth M. Hall
Johanna J. Kenyon
Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid
Communications Biology
title Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid
title_full Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid
title_fullStr Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid
title_full_unstemmed Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid
title_short Phage-encoded enzymes found in Acinetobacter baumannii convert pseudaminic acid to 8-epipseudaminic acid
title_sort phage encoded enzymes found in acinetobacter baumannii convert pseudaminic acid to 8 epipseudaminic acid
url https://doi.org/10.1038/s42003-025-08114-8
work_keys_str_mv AT nowshinssharar phageencodedenzymesfoundinacinetobacterbaumanniiconvertpseudaminicacidto8epipseudaminicacid
AT andreaiovine phageencodedenzymesfoundinacinetobacterbaumanniiconvertpseudaminicacidto8epipseudaminicacid
AT cristinadecastro phageencodedenzymesfoundinacinetobacterbaumanniiconvertpseudaminicacidto8epipseudaminicacid
AT ruthmhall phageencodedenzymesfoundinacinetobacterbaumanniiconvertpseudaminicacidto8epipseudaminicacid
AT johannajkenyon phageencodedenzymesfoundinacinetobacterbaumanniiconvertpseudaminicacidto8epipseudaminicacid