Structure of the O-polysaccharide of Proteus penneri 28 and Proteus vulgaris O31 and classification of P. penneri 26 and 28 in Proteus serogroup O31

The lipopolysaccharides (LPS) of Proteus penneri 28 and Proteus vulgaris O31 (PrK 55/57) were degraded with dilute acetic acid and structurally identical high-molecular-mass O-polysaccharides were isolated by gel-permeation chromatography. Sugar analysis and nuclear magnetic resonance (NMR) spectroscopic studies showed that both polysaccharides contain D-GlcNAc, 2-acetamido-2,6-dideoxy-L-glucose (L-2-acetamido-2,6-dideoxyglucose (N-acetylquinovosamine)) and 2-acetamido-3-O-[(S)-1-carboxyethyl]-2-deoxy-D-glucose (N-acetylisomuramic acid) and have the following structure: [carbohydrate structure: see text] where (S)-1-carboxyethyl [a residue of (S)-lactic acid] (S-Lac) is an ether-linked residue of (S)-lactic acid. The O-polysaccharide studied is structurally similar to that of P. penneri 26, which differs only in the absence of S-Lac from the GlcNAc residue. Based on the O-polysaccharide structures and serological data of the LPS, it was suggested classifying these strains in one Proteus serogroup, O31, as two subgroups: O(31a), 31b for P. penneri 28 and P. vulgaris PrK 55/57 and O31a for P. penneri 26. A serological relatedness of the LPS of Proteus O(31a), 31b and P. penneri 62 was revealed and substantiated by sharing epitope O31b, which is associated with N-acetylisomuramic acid. It was suggested that a cross-reactivity of P. penneri 28 O-antiserum with the LPS of several other P. penneri strains is due to a common epitope(s) on the LPS core.     

Characterization of epitope specificity of Proteus penneri 7 lipopolysaccharide core region

To extend the knowledge on the fragments of Proteus penneri lipopolysaccharide core regions, which determine the cross-reactions with specific antibodies, serological studies were performed by use of P. penneri 7 core-specific antiserum and Proteus sp. lipopolysaccharides. Different reactivity of the tested antiserum with three groups of antigens suggested differences in their core regions' epitope specificity. Comparing the results of the serological investigations with the previously determined structures of the core regions of the tested P. penneri lipopolysaccharides allowed distinguishing two potential tri- and tetrasaccharide epitopes and a third fragment which could not be determined precisely.     

Structure of the O-polysaccharide leads to classification of Proteus penneri 31 in Proteus serogroup O19

O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide (LPS) of Proteus penneri strain 31. Sugar and methylation analyses along with NMR spectroscopic studies, including 2D 1H,1H COSY, TOCSY, ROESY, 1H,13C and 1H,31P HMQC experiments, demonstrated the following structure of the polysaccharide: [carbohydrate structure: see text] where FucNAc is 2-acetamido-2,6-dideoxygalactose and EtnP is 2-aminoethyl phosphate. The polysaccharide studied has the same carbohydrate backbone as the O-polysaccharide of Proteus vulgaris O19. Based on this finding and close serological relatedness of the LPS of the two strains, it is proposed to classify P. penneri 31 in Proteus serogroup O19 as an additional subgroup. In contrast, D-GlcNAc6PEtn and alpha-L-FucNAc-(1-->3)-D-GlcNAc shared with a number of other Proteus O-polysaccharides could not provide any significant cross-reactivity of the corresponding LPS with rabbit polyclonal O-antiserum against P. penneri 31.     

Structure and serological studies of the O-polysaccharide of Proteus penneri 75 Epitopes and subgroups of Proteus serogroup O73

The O-specific polysaccharide of the lipopolysaccharide of Proteus penneri strain 75 consists of tetrasaccharide-ribitol phosphate repeating units and resembles ribitol teichoic acids of Gram-positive bacteria. The following structure of the polysaccharide was elucidated by chemical methods and 1H and 13C NMR spectroscopy: [structure in text] where Rib-ol is ribitol. Serological studies with polyclonal antisera showed that the same structure of the O-polysaccharide occurred in two strains: P. penneri 75 and 128. A similar structure has been established earlier for the O-polysaccharide of P. penneri 103 [Drzewiecka, D., et al., Carbohydr. Res. 337 (2002) 1535-1540]. On the basis of complex serological investigations with use of two polyclonal P. penneri 75 and 103 O-antisera, five strains could be classified into Proteus O73 serogroup: P. penneri 48, 75, 90, 103 and 128, two of which (P. penneri 75 and 128) should be subdivided into subgroup 73a, 73b and three others (P. penneri 48, 90 and 103) into subgroup 73a, 73c. Epitopes responsible for the cross-reactivity of P. penneri O73 strains and a related strain of P. mirabilis O20 were tentatively defined.     

The structure of the core part of Proteus penneri strain 16 lipopolysaccharide

The structure of the carbohydrate backbone of the lipid A-core region of the lipopolysaccharide (LPS) from Proteus penneri strain 16 was determined using NMR and chemical analysis of the core oligosaccharide, obtained by mild acid hydrolysis of the LPS, and of the products of alkaline deacylation of the LPS: formula [see text]. Incomplete substitution is indicated by bold italics. All sugars are in the pyranose form, alpha-Hep is the residue of L-glycero-alpha-D-manno-Hep, alpha-DD-Hep is the residue of D-glycero-alpha-D-manno-Hep, Bu is the (R)-3-hydroxybutyryl residue.     

暹罗鳄食道结节病病原彭氏变形杆菌的分离与鉴定

【背景】2016年5月,厦门南顺鳄鱼园中的养殖暹罗鳄(Crocodylussiamensis)幼鳄暴发了一种之前未见报道的食道结节病,表现为鳄鱼不进食并伴有部分死亡。【目的】对患食道结节病的鳄鱼病料进行病原学鉴定,旨在探明病因,为该病的防治提供理论参考依据。【方法】对鳄鱼病灶处分离菌进行生理生化特征鉴定、16S rRNA基因序列分析、回接感染试验以及药敏试验。【结果】从病鳄食道、肝脏和血液病灶处各分离到一株优势细菌,综合菌株形态、生理生化特征以及16S rRNA基因序列分析的结果,判定3株分离菌均为彭氏变形杆菌(Proteus penneri)。由食道结节处分离的菌株2202经人工回接感染,证实彭氏变形杆菌为引起此次暹罗鳄发病死亡的致病原。3株分离菌对12种药物的耐药率均为33%,对恩诺沙星、复方新诺明、头孢噻肟、卡那霉素、四环素、强力霉素与萘啶酸共7种实验药物敏感,对利福平、青霉素G、红霉素和氯霉素耐药,而对链霉素则表现中介。【结论】彭氏变形杆菌与患病暹罗鳄的死亡有直接关系,该菌多为侵袭人类的条件致病菌,作为养殖鳄鱼的病原菌尚属首例。     

Investigation of hydrophobicity of Proteus vulgaris strains and ability of Proteus vulgaris and Proteus penneri strains to penetrate bladder membrane HCV T-29 cells

Proteus bacilli play a particularly important role in urinary tract infections (UTI). Fimbriae and adherence ability and hemolysins production (HpmA, HlyA) are one of the factors of pathogenicity of these bacteria. In this paper we describe the invasion of HCV T-29 transitional bladder urothelial cells carcinoma strains of P. penneri, as well as P. vulgaris strains belonging to different serogroups. The cytotoxic effect was observed at 8 hour of incubation of the tested cells with P. vulgaris O21 and the same effect (complete lysis) at 6 hours by P. vulgaris O4 (this strain manifests maximal activity in the production of HlyA hemolysin). P. penneri strains, produce different types of fimbriae, expressed similar bacterial invasiveness. The hydrophobic properties of 25 P. vulgaris strains were also tested and only 3 strains occur to have hydrophobic cell surface.     

Structure of the O-specific polysaccharide of Proteus penneri 103 containing ribitol and 2-aminoethanol phosphates

The O-specific polysaccharide of the lipopolysaccharide of Proteus penneri strain 103 was studied using 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, NOESY, H-detected 1H,(13)C HMQC, 1H, 31P HMQC, and HMBC experiments. It was found that the polysaccharide is built up of oligosaccharide-ribitol phosphate repeating units and thus resembles ribitol teichoic acids of Gram-positive bacteria. The following structure of the polysaccharide was established:where Etn and Rib-ol are ethanolamine and ribitol, respectively. This structure is unique among the known structures of Proteus O-antigens and, therefore, we propose classification of the strain studied into a new Proteus serogroup, O73. The molecular basis for cross-reactivity between O-antiserum against P. penneri 103 and O-antigens of P. mirabilis O33 and D52 is discussed.     

Structure of the O-specific polysaccharide of Proteus penneri 71 and classification of cross-reactive P. penneri strains to a new proposed serogroup O64.

A neutral O-specific polysaccharide (O-antigen) was isolated from the lipopolysaccharide (LPS) of the bacterium Proteus penneri 71. On the basis of sugar analysis and 1H- and 13C-NMR spectroscopic studies, including two-dimensional COSY, 13C,1H heteronuclear COSY and ROESY, the following structure of the trisaccharide repeating unit of the polysaccharide was established: -->3)-beta-D-GlcpNAc-(1-->4)-beta-D-GlcpNAc-(1-->3)-alpha-D-Galp-(1-- > The polysaccharide has the same carbohydrate backbone as the O-specific polysaccharide of P. penneri 19 and both are similar to that of P. penneri 62 studied by us previously. A cross-reactivity of anti-P. penneri 71, 19 and 62 O-antisera with 11 P. penneri strains was revealed and substantiated at the level of the O-antigen structures. These strains could be divided into three subgroups within a new proposed Proteus O64 serogroup containing P. penneri strains only.     

Structural and serological relatedness of the O-antigens of Proteus penneri 1 and 4 from a novel Proteus serogroup O72.

O-specific polysaccharides (O-antigens) of the lipopolysaccharides (LPS) of Proteus penneri strains 1 and 4 were studied using sugar analysis, (1)H and (13)C NMR spectroscopy, including 2D COSY, H-detected (1)H,(13)C HMQC, and rotating-frame NOE spectroscopy (ROESY). The following structures of the tetrasaccharide (strain 1) and pentasaccharide (strain 4) repeating units of the polysaccharides were established: [reaction: see text]. In the polysaccharide of P. penneri strain 4, glycosylation with the lateral Glc residue (75%) and O-acetylation of the lateral GalNAc residue (55%) are nonstoichiometric. This polysaccharide contains also other, minor O-acetyl groups, whose positions were not determined. The structural similarity of the O-specific polysaccharides was consistent with the close serological relatedness of the LPS, which was demonstrated by immunochemical studies with O-antisera against P. penneri 1 and 4. Based on these data, it was proposed to classify P. penneri strains 1 and 4 into a new Proteus serogroup, O72, as two subgroups, O72a and O72a,b, respectively. Serological cross-reactivity of P. penneri 1 O-antiserum with the LPS of P. penneri 40 and 41 was substantiated by the presence of an epitope(s) on the LPS core region shared by all P. penneri strains studied.     

Identification and typing of Proteus penneri and Proteus vulgaris biogroups 2 and 3, from clinical sources, by computerized analysis of electrophoretic protein patterns

Seventy-six strains of the Proteus vulgaris complex ( Pr. penneri and Pr. vulgaris biogroups 2 and 3) were characterized by one-dimensional SDS-PAGE of cellular proteins. The protein patterns were highly reproducible. The strains came from various countries and were mainly of human origin: urine (28), respiratory tract (13), wounds (8), faeces (7), blood (3), miscellaneous sources (6) and unknown sources (11). The patterns of these strains, together with those of the type strains of seven Morganella, Proteus and Providencia species were subjected to two numerical analyses. In the first, in which the principal protein bands (in the 35.0–42.0 kDa range) were excluded, the strains of the Pr. vulgaris complex formed four clusters at the 83% similarity level. These corresponded to Pr. penneri, Pr. vulgaris biogroup 2, and two clusters (3a and 3b) represented biogroup 3. Each of these clusters was distinct from the Morganella, Proteus and Providencia reference strains. In the second analysis, which included all the protein bands, the 41 Pr. penneri strains showed little heterogeneity but 17 subphenons could be recognized among the 35 strains of Pr. vulgaris biogroups 2 and 3. These results support the division of biogroup 3 strains into at least two separate taxa. Other results indicate that biogroup 3 is heterogeneous and may contain further genomic groups. The method also provides a basis for typing clinical strains of Pr. vulgaris biogroups 2 and 3.     

The structure of the O-specific polysaccharide chain of Proteus penneri strain 16 lipopolysaccharide

O-Specific polysaccharide was obtained by mild acid degradation of Proteus penneri strain 16 lipopolysaccharide and found to contain D-glucose, D-glucuronic acid, 2-acetamido-2-deoxy-D-glucose, and 3,6-dideoxy-3-[(R)-3-hydroxybutyramido]- D-galactose in the ratio of 2:1:1:1 as well as a small proportion of O-acetyl groups. On the basis of one-dimensional 1H-NMR13C-NMR and NOE spectroscopy, two-dimensional homonuclear-shift-correlated spectroscopy with one-step and two-step relayed coherence transfer and heteronuclear 1H/13C NMR shift-correlated spectroscopy, it was concluded that the O-specific polysaccharide of P. penneri strain 16 has the following structure: (formula; see text) This structure was confirmed by methylation analysis and structural analysis of a linear tetrasaccharide fragment prepared by cleavage of the polysaccharide with anhydrous hydrogen fluoride followed by conversion of the alpha-tetrosyl fluoride obtained in to the corresponding free oligosaccharide and alditol. O-Acetyl groups were tentatively located at position 3 of the glucuronic acid residue and at position 4 of the 6-substituted glucose residue, the degree of acetylation being less than 20% of the total. Cross-reactions of P. penneri strain 16 anti-(O-specific polysaccharide) antiserum with lipopolysaccharides from several other Proteus strains and the role of 3,6-dideoxy-3-(R)-3-hydroxybutyramido-D-galactose in the serological specificity of P. penneri strain 16 are discussed.     

Structure of the O-polysaccharide and serological studies of the lipopolysaccharide of Proteus penneri 60 classified into a new Proteus serogroup O70

An alkali-treated lipopolysaccharide of Proteus penneri strain 60 was studied by chemical analyses and 1H, 13C and 31P NMR spectroscopy, and the following structure of the linear pentasaccharide-phosphate repeating unit of the O-polysaccharide was established: 6)-alpha-D-Galp-(1-->3)-alpha-L-FucpNAc-(1-->3)-alpha-D-GlcpNAc-(1-->3)-beta-D-Quip4NAc-(1-->6)-alpha-D-Glcp-1-P-(O--> Rabbit polyclonal O-antiserum against P. penneri 60 reacted with both core and O-polysaccharide moieties of the homologous LPS. Based on the unique O-polysaccharide structure and serological data, we propose to classify P. penneri 60 into a new, separate Proteus serogroup O70. A weak cross-reactivity of P. penneri 60 O-antiserum with the lipopolysaccharide of Proteus vulgaris O8, O15 and O19 was observed and discussed in view of the chemical structures of the O-polysaccharides.     

Mobilization for transfer of the nonconjugative plasmid pAP/57Hly by different conjugative plasmids

The ability for mobilization of E. coli pAP57Hly nonconjugative plasmid which codes for beta-hemolysis production was investigated. It was shown that mobilization of pAP57Hly nonconjugative plasmid does not depend on the incompatibility groups, pili nature, host range of transmissible activity of conjugative plasmids. The data obtained exclude the mechanism of mobilization in which the cointegrative structures are formed.     

营养胁迫下球形棕囊藻(Phaeocystis globosa Scherffel)的生长行为及溶血活性

近年来,我国广东沿海连续出现大面积球形棕囊藻(Phaeocystis globosaScherffel)赤潮,产生溶血毒素等有害物质,给当地的海洋养殖业造成重大的经济损失。研究不同的生长时期及半连续培养时不同营养盐胁迫下,球形棕囊藻溶血毒素的产生行为。结果显示,批量培养的球形棕囊藻处于生长平稳期末时,溶血活性最大((21±1)units/L);半连续培养时,营养盐限制对球形棕囊藻的生长有明显的抑制作用,其中Fe3 及N盐限制影响最为明显。同时,营养盐限制也可促进棕囊藻溶血毒素的合成,其中Fe3 和-Mn2 的限制性时球形棕囊藻溶血活性显著增强。这些结果表明,球形棕囊藻溶血毒素的产生与藻细胞的生长可能受不同机制的调节,溶血毒素的合成可能是环境胁迫下棕囊藻维持生存的一种策略。     

Some biological features of Proteus bacilli. 2. Haemolytic activities of Proteus mirabilis and Proteus vulgaris strains

The haemolytic activities of Proteus mirabilis and P. vulgaris strains were studied under different conditions. No filterable alpha haemolysin could be detected in P. mirabilis uropathogens provided from patients with urinary tract infections. Together with the results presented in the accompanying paper, in which three clinical isolates with temporary ability to produce a soluble haemolysin were described, the occurrence of alpha haemolytic P. mirabilis isolates did not exceed 3%. Cell bound beta haemolysin is present in nearly 35% of P. mirabilis urinary strains. Another kind of haemolytic activity was observed when P. mirabilis and P. vulgaris strains were grown in liquid media supplemented with erythrocytes. During the logarithmic growth phase nearly 100% of P. mirabilis and P. vulgaris strains of various origin haemolyzed 100-50% of erythrocytes. Except for Serratia, the other representatives of Enterobacteriaceae did not demonstrate such activity in the same conditions. The preliminary characteristics of this phenomenon is given.     

Antimicrobial and hemolytic activities of gradex]

Gradex is a polymer preparation resulting from formation of covalent bonds between the molecules of gramicidin S, a polypeptide antibiotic, and dextran, a polymeric carrier. Antimicrobial and hemolytic activities of gradex were studied. It was shown that the antimicrobial activity of gradex was due to the presence of gramicidin S in its composition. The activity level was lower than that of gramicidin S. It was also found that the gradex reduced form in concentrations up to 300 micrograms/ml had practically no hemolytic effect against human erythrocytes. The reduced form of gradex is promising for development of an artificial ++anti-brucellosis vaccine.