Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Biol Macromol ; 218: 447-455, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35872312

RESUMO

The K98 capsular polysaccharide (CPS) from the Acinetobacter baumannii clinical isolate, REV-1184, was studied by sugar analysis and Smith degradation along with one- and two-dimensional 1H and 13C NMR spectroscopy and high-resolution electrospray ionization mass spectrometry. The CPS was found to consist of linear tetrasaccharide repeats (K-units) that include one residue each of d-GlcpNAc, d-GalpNAc, 2-acetamido-2-deoxy-d-galacturonic acid (d-GalpNAcA), and 2-acetamido-2,6-dideoxy-d-glucose (N-acetylquinovosamine, d-QuipNAc), with the GalpNAc residue decorated with a (R)-configurated 4,6-pyruvic acid acetal group. The CPS has a similar composition to that of A. baumannii K4 but the topology of the tetrasaccharide K-unit is different (linear in K98 versus branched in K4). This was due to a difference in sequence for the Wzy polymerases encoded by the CPS biosynthesis gene clusters KL98 and KL4, with the WzyK98 polymerase forming a ß-d-QuipNAc-(1→3)-d-GalpNAc linkage between the K98 units.


Assuntos
Acinetobacter baumannii , Acinetobacter baumannii/química , Acinetobacter baumannii/genética , Família Multigênica , Polissacarídeos Bacterianos/química , Piruvatos
2.
Int J Mol Sci ; 22(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073255

RESUMO

Whole genome sequences of two Acinetobacter baumannii clinical isolates, 48-1789 and MAR24, revealed that they carry the KL106 and KL112 capsular polysaccharide (CPS) biosynthesis gene clusters, respectively, at the chromosomal K locus. The KL106 and KL112 gene clusters are related to the previously described KL11 and KL83 gene clusters, sharing genes for the synthesis of l-rhamnose (l-Rhap) and 6-deoxy-l-talose (l-6dTalp). CPS material isolated from 48-1789 and MAR24 was studied by sugar analysis and Smith degradation along with one- and two-dimensional 1H and 13C NMR spectroscopy. The structures of K106 and K112 oligosaccharide repeats (K units) l-6dTalp-(1→3)-D-GlcpNAc tetrasaccharide fragment share the responsible genes in the respective gene clusters. The K106 and K83 CPSs also have the same linkage between K units. The KL112 cluster includes an additional glycosyltransferase gene, Gtr183, and the K112 unit includes α l-Rhap side chain that is not found in the K106 structure. K112 further differs in the linkage between K units formed by the Wzy polymerase, and a different wzy gene is found in KL112. However, though both KL106 and KL112 share the atr8 acetyltransferase gene with KL83, only K83 is acetylated.


Assuntos
Acinetobacter baumannii , Desoxiaçúcares , Hexoses , Polissacarídeos Bacterianos , Acinetobacter baumannii/química , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Desoxiaçúcares/química , Desoxiaçúcares/genética , Desoxiaçúcares/metabolismo , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Hexoses/química , Hexoses/genética , Hexoses/metabolismo , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/genética , Polissacarídeos Bacterianos/metabolismo , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...