Structure of a neutral glycan isolated from the lipopolysaccharide of the reference strain for Serratia marcescens serogroup O22

Both a neutral and an acidic polymer have been isolated from a lipopolysaccharide extract of the reference strain for Serratia marcescens serogroup O22. The neutral polymer has a linear structure with the repeating unit shown. The same tetrasaccharide unit also forms the backbone of the branched neutral polymer isolated from the reference strain for serogroup O10, which cross-reacts strongly with O22. ----2)-alpha-L-Rhap-(1----2)-alpha-L-Rhap-(1----3)-alpha-L-+ ++Rhap-(1----3)-alpha- D-GlcpNAc-(1----     

Structure of a neutral polymer isolated from the lipopolysaccharide of the reference strain for Serratia marcescens serogroup O18

A neutral polymer (the putative O antigen) has been isolated from the lipopolysaccharide of the reference strain for Serratia marcescens serogroup 018. From the results of spectroscopic and degradative studies, the repeating unit of the polymer was identified as a linear tetrasaccharide having the structure shown. ----2)-alpha-L-Rhap-(1----2)-alpha-L-Rhap-(1----6)-alpha-D- GlcpNAc-(1----     

Structure of the O-specific polysaccharide from the lipopolysaccharide of Serratia marcescens O8

Structural studies have been carried out on the O-specific polysaccharide from the lipopolysaccharide of the reference strain (CDC 1604-55) for serogroup O8 of Serratia marcescens. The polymer has a branched, tetrasaccharide repeating unit of D-galactose(Gal),D-glucose(Glc), and 2-acetamido-2-deoxy-D-glucose(GlcNAc) with the following structure: (Formula: see text). The anomeric configuration assigned to the glucose residue differs from that (beta) previously proposed [Tarcsay, L., Wang, C. S., Li, S.-C. and Alaupovic, P. (1973) Biochemistry 12, 1948-1955]. The structure of the O8 polymer is identical with that of one of two polymers present in the cell envelope of a strain (CDC 1783-57) of S. marcescens O14.     

Structure of an acidic glycan present in the lipopolysaccharide extract from the reference strain for Serratia marcescens serogroup O18.

The lipopolysaccharide extract from the cell wall of the reference strain for Serratia marcescens serogroup O18 contained, in addition to a neutral glycan characterised previously, an acidic glycan. Acidity was contributed both by D-glucuronic acid and by 4-O-[(R)-1-carboxyethyl]-D-glucose (4-O-Lac-D-Glc). By using n.m.r. spectroscopy, methylation analysis, and chemical degradations, the repeating unit of the acidic glycan was identified as a branched hexasaccharide having the structure shown; an O-acetyl group also present was not located. The glycan is believed to define the O18 serogroup, but is probably not an integral component of the lipopolysaccharide. [formula: see text].     

Structure of a neutral glycan from the lipopolysaccharides of reference strains for Serratia marcescens serogroups O2 and O3

Serogroups O2 and O3 of Serratia marcescens are differentiated by acidic glycans present in the aqueous phase when lipopolysaccharides are extracted from the reference strains by the aqueous-phenol method. The phenolic phases of these extracts from both strains also contain lipopolysaccharides, from which the same neutral glycan is released on milk acid hydrolysis. The neutral glycan has the disaccharide repeating-unit shown, and accounts for the cross-reactions between the two serogroups and also with serogroup O21: --> 4)-alpha-D-GlcpNAc-(1-->4)-beta-D-ManpNAc-(1--.     

Structure of the O-specific polysaccharide from the lipopolysaccharide of Citrobacter gillenii O11, strain PCM 1540

The O-specific polysaccharide of the lipopolysaccharide of Citrobacter gillenii PCM 1540 (serogroup O11) consists of D-Glc, D-Man, D-GalNAc, D-GlcNAc, 2-acetamido-2,6-dideoxy-D-galactose (D-FucNAc) and O-acetyl groups in the ratios 2:1:1:1:1:1. On the basis of sugar and methylation analyses and Smith-degradation along with 1D and 2D 1H and 13C NMR spectroscopy, the following structure of the branched hexasaccharide repeating unit was established: [structure: see text]. Citrobacter werkmanii PCM 1541 belonging to the same serogroup O11 was found to have an R-form lipopolysaccharide devoid of the O-specific polysaccharide.     

Structure of the O-specific polysaccharide for Acinetobacter baumannii serogroup O1.

A polymeric fraction containing D-galactose, N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine was isolated from the lipopolysaccharide produced by the reference strain for Acinetobacter baumannii serogroup O1. By means of NMR spectroscopy, methylation analysis, and chemical degradation, the repeating unit of the polymer was identified as a branched trisaccharide of the following structure. [formula: see text].     

Structural studies of glucorhamnans isolated from the lipopolysaccharides of reference strains for Serratia marcescens serogroups O4 and O7, and of an O14 strain

Partially acetylated glucorhamnans have been isolated from the lipopolysaccharides of three strains of Serratia marcescens. The polymer from the reference strain (C.D.C. 864-57) for serogroup O4 has the disaccharide repeating-unit shown below, in which acetylation at position 2 of the rhamnosyl residue is approximately 90% complete. Similar glucorhamnans from the reference strain (C.D.C. 843-57) for serogroup O7 and from a pigmented strain (NM) of serogroup O14 differ only in the configuration of the L-rhamnopyranosyl residue (beta) and the extent of O-acetylation (O7, almost stoichiometric; NM, 80-90%). Glucorhamnans of the second type have been isolated previously from the lipopolysaccharides of other strains of S. marcescens, including the reference strain for serogroup O6 and another pigmented O14 strain (N.C.T.C. 1377). In all cases, the lipopolysaccharide extracts also contained acidic glycans, but the glucorhamnans are believed to constitute the integral side-chains. (Formula: see text).     

Structure of the O-specific polysaccharide isolated from the lipopolysaccharide of Citrobacter gillenii serotype O12a, 12b strain PCM 1544

A neutral O-specific polysaccharide was isolated from the lipopolysaccharide of Citrobacter gillenii strain PCM 1544, representing serotype O12a,12b. The polysaccharide was studied by sugar and methylation analyses and Smith degradation along with 1H and 13C NMR spectroscopy, including a ROESY experiment. The following structure of the tetrasaccharide repeating unit was established, in which substitution with terminal GlcNAc is approximately 60%. [structure: see text]     

Structure of the O-specific polysaccharide chain of the lipopolysaccharide from Yersinia intermedia serotype O:4.33

O-specific polysaccharide has been isolated on autohydrolysis of lipopolysaccharide from Yersinia intermedia O: 4.33 (strain 1476) and shown to consist of the yersiniose B (3.6-dideoxy-4-C-(1-hydroxyethyl)-xylo-hexose) and 2-acetamido-2-deoxy-D-galactose residues in a molar ratio of 1 : 2. Acid hydrolysis, methylation. solvolysis with anhydrous hydrogen fluoride. and 13C-NMR studies indicate the polysaccharide to be composed of trisaccharide repeating units of the following structure: (Formula: see text).     

Structure of the O-specific polysaccharide from Enterobacter cloacae strain N.C.T.C. 11579 (serogroup O10)

The O-specific polysaccharide from the reference strain (N.C.T.C. 11579) for Enterobacter cloacae serogroup O10 has been isolated and characterised. By means of n.m.r. spectroscopy and methylation analysis, and by studies of the products obtained by Smith degradation or by N-deacetylation-deamination, the repeating unit of the polysaccharide could be allocated the structure shown. The polysaccharides from two cross-reacting serogroups (O9 and O11) have the same monosaccharide composition. (Formula: see text)     

Structure of the acidic microcapsular glycan from the reference strain (C.D.C. 6320-58) for Serratia marcescens serotype O14:K12

The acidic polysaccharide from Serratia marcescens serogroup O14:K12 was analyzed by means of chemical studies and NMR spectroscopy and its repeating unit structure found to be carbohydrate sequence [see text] O-Acetyl groups are proposed to be present in non-stoichiometric amounts on O-6 on one of the hexose residues in the main chain.     

Functional characteristics of the recA gene from Serratia marcescens strain Sb

The cloned recA gene from Serratia marcescens Sb was expressed and complemented defects in the UV repair, recombination, and SOS induction of an Escherichia coli host deleted for recA. Moreover, the Serratia gene, recA (Sm), supported the same frequency of recombination per unit length of DNA as did the homologous Escherichia coli gene, recA(Ec).     

Structure of the sialic acid-containing O-specific polysaccharide from Salmonella enterica serovar Toucra O48 lipopolysaccharide.

Lipopolysaccharide was extracted from cells of Salmonella enterica serovar Toucra O48 and, after mild acid hydrolysis (1% AcOH, 1 h, 100 degrees C or 0.1 M NaOH-AcOH, pH 4.5, 5 h, 100 degrees C), the O-specific polysaccharide was isolated and characterized. The core and an oligosaccharide containing a fragment of the repeating unit linked to the core region were also obtained, depending on hydrolysis conditions. On the basis of sugar and methylation analyses and NMR spectroscopy of the hydrolysis products, the biological repeating unit of the O-specific polysaccharide was shown to be the following trisaccharide: -->4)-alpha-Neup5Ac(2-->3)-L-alpha-FucpNAc(1-->3)-D-beta-Glc pNAc(1--> The polysaccharide O-chain was substituted with a single molar equivalent of O-acetyl group, distributed between the Neu5Ac O-9 and O-7 positions, in an approximate ratio of 7 : 3.     

Structure of the O-specific polysaccharide of Proteus mirabilis D52 and typing of this strain to Proteus serogroup O33.

The acidic O-specific polysaccharide chain (O-antigen) of the lipopolysaccharide (LPS) of Proteus mirabilis strain D52 was studied using chemical analyses along with 1H-NMR and 13C-NMR spectroscopy, including 2D COSY, TOCSY, ROESY, H-detected 1H,13C and 1H,31P HMQC experiments. The polysaccharide was found to contain D-ribitol 5-phosphate (D-Rib-ol-5-P) and ethanolamine phosphate (Etn-P) and has the following structure: D-Rib-ol-5-P (3) approximately 75% EtnP(6)-->2)-beta-D-Galp-(1-->3)-alpha-D-GlcpNAc-(1-->3)-beta-D-Glcp-(1-->3)-beta-D-GlcpNAc-(1-->). This structure is identical with that of the O-polysaccharide of P. mirabilis O33 strain 59/57, and, hence, P. mirabilis D52 belongs to the same Proteus serogroup O33. Serological studies with O-antiserum against P. mirabilis D52 confirmed this but showed that the LPS species of P. mirabilis 59/57 and D52 are not identical, having different epitopes in the core region. A serological cross-reactivity of P. mirabilis D52 O-antiserum was observed with LPS of two other Proteus strains, P. mirabilis O16 and P. penneri 103, which have structurally different O-polysaccharides. The role of charged groups, Rib-ol-5-P and Etn-P in the immunospecificity is discussed.     

Structure of the putative O antigen containing 2-amino-2-deoxy-L-glucose in the reference strain for Pseudomonas cepacia serogroup O1.

Polymeric material isolated from the lipopolysaccharide of the reference strain of Pseudomonas cepacia serogroup O1 consisted mainly of D-glucose and 2-amino-2-deoxy-L-glucose: rhamnose and O-acetyl groups were also present. As a result of spectroscopic and degradative studies, the disaccharide repeating-unit shown could be assigned to the major polymer present. A possible origin of the minor components is suggested. ----4)-alpha-D-Glcp-(1----3)-alpha-L-GlcpNAc-(1----.