Open AccessStructure and serological properties of the O‐antigen of two clinical Proteus mirabilis strains classified into a new Proteus O77 serogroup
Author(s) -
Drzewiecka Dominika,
Arbatsky Nikolay P.,
Shashkov Alexander S.,
Stączek Paweł,
Knirel Yuriy A.,
Sidorczyk Zygmunt
Publication year - 2008
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.2008.00462.x
Subject(s) - proteus mirabilis , proteus , microbiology and biotechnology , antigen , biology , antiserum , epitope , serology , proteus vulgaris , antibody , escherichia coli , biochemistry , immunology , gene
Two Proteus mirabilis strains, 3 B‐m and 3 B‐k, were isolated from urine and faeces of a hospitalized patient from Lodz, Poland. It was suggested that one strain originated from the other, and the presence of the bacilli in the patient's urinary tract was most probably a consequence of autoinfection. The O‐polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of P. mirabilis 3 B‐m and studied by sugar analysis and nuclear magnetic resonance spectroscopy, including two‐dimensional rotating frame Overhause effect spectroscopy (ROESY) and 1 H, 13 C heteronuclear single quantum coherence (HSQC) experiments. The following structure of the linear trisaccharide‐repeating unit of the O‐polysaccharide was established:→2)‐β‐D‐Glc p ‐(1→3)‐α‐L‐6dTal p 2Ac‐(1→3)‐β‐D‐Glc p NAc‐(1→where 6dTal2Ac stands for 2‐ O ‐acetyl‐6‐deoxy‐L‐talose. It resembles the structure of the O‐polysaccharide of Proteus penneri O66, which includes additional lateral residues of 2,3‐diacetamido‐2,3,6‐trideoxy‐L‐mannose. The lipopolysaccharides from two P. mirabilis strains studied were serologically identical to each other but not to that from any of the existing 76 Proteus O‐serogroups. Therefore, the strains were classified into a new O77 serogroup specially created in the genus Proteus . Serological studies using Western blot and enzyme‐linked immunosorbent assay with intact and adsorbed O‐antisera showed that the P. mirabilis O77 antigen is related to Proteus vulgaris O2 and P. penneri O68 antigens, and a putative disaccharide epitope responsible for the cross‐reactivity was revealed.