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1.
Outbreaks of Shigella sonnei associated with contaminated water have been reported and methods for the simultaneous detection of Shigellae and enteroinvasive Escherichia coli in water samples have been developed with detection limits of 10(1)-10(2) CFU mL(-1) of water. Because 10(1)-10(2)Shigellae can cause disease, a more sensitive detection method as an addition to the existing methods for detection of Shigella sonnei in water samples is reported here. Initially, 33 Shigella sonnei and 72 non-Shigella sonnei isolates were tested and one primer pair was found capable of specifically amplifying a 369-bp insertion sequence 1 (IS1) fragment from all 33 Shigella sonnei isolates and one Shigella dysenteriae ATCC isolate by PCR. The detection method was developed, which included filtration of 50 mL of water through a membrane and application of PCR to the membrane using this primer pair. Environmental water samples with total bacterial numbers of 384-2.84 x 10(7) CFU L(-1) were collected and seeded with 13 Shigella sonnei and the Shigella dysenteriae ATCC isolates. Detection limits were determined as 1.7-24.7 and 270-8000 CFU per 50 mL of water, respectively, using this detection method. 相似文献
2.
K V Bunin G A Iusova E G Kravtsov O F Belaia N G Va?sbord 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(8):78-80
The level of circulating immune complexes has been determined in 53 patients in the dynamics of the disease. For the first time circulating immune complexes have been found to contain Shigella sonnei K-antigen and Shigella flexneri O-antigen, as well as IgA, IgG and IgM to Shigella. Shigella antigens can be detected from the first week of the disease, and their occurrence does not depend on the level of circulating complexes in patients blood serum. 相似文献
3.
Iu M Romanova I A Nastichkin A I Martsinkovskaia I A Rudnev V G Petrovskaia 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1987,(9):19-24
The plasmid pSS120, determining the synthesis of species specific I phase antigen of Shigella sonnei is mobilized for genetic transfer into E. coli K12 recipient cells with the frequency 12-41%. The frequency depends on the type of mobilized plasmid and recipient strain. The I phase antigen is normally expressed in II phase recipient cells and in E. coli cells. During mobilization pSS120 forms cointegrates representing a recombinant of mobilizing and mobilized plasmids DNA. The study of pSS120 inheritance stability has shown the plasmid to be unstable during culturing of bacteria and to be partially lost from the parent Shigella sonnei strains as well as from the "hybrid" transconjugants obtained. The 60 Md plasmid present in the donor strains of Shigella sonnei is prone to structural fragmentation particularly expressed in Shigella sonnei/E. coli hybrids. 相似文献
4.
Two cytolethal distending toxin (Cdt) type V-encoding bacteriophages (Φ62 and Φ125) were induced spontaneously from their wild-type Escherichia coli strains and from the lysogens generated in Shigella sonnei. The stability of Cdt phages was determined at various temperatures and pH values after 1 month of storage by means of infectivity tests using a plaque blot assay and analysis of phage genomes using real-time quantitative PCR (qPCR): both were highly stable. We assessed the inactivation of Cdt phages by thermal treatment, chlorination, UV radiation, and in a mesocosm in both summer and winter. The results for the two Cdt phages showed similar trends and were also similar to the phage SOM23 used for reference, but they showed a much higher persistence than Cdt-producing E. coli. Cdt phages showed maximal inactivation after 1 h at 70°C, 30 min of UV radiation, and 30 min of contact with a 10-ppm chlorine treatment. Inactivation in a mesocosm was higher in summer than in winter, probably because of solar radiation. The treatments reduced the number of infectious phages but did not have a significant effect on the Cdt phage particles detected by qPCR. Cdt phages were quantified by qPCR in 73% of river samples, and these results suggest that Cdt phages are a genetic vehicle and the natural reservoir for cdt in the environment. 相似文献
5.
The interaction of the whole blood from patients with dysentery and gastrointestinal diseases of non-dysenteric etiology, with the causative agents of dysentery, Sh. sonnei and Sh. flexneri, and saprophytic, staphylococci labeled with radioactive isotopes was studied in vitro. In dysentery an increase in the capacity of the blood for Shigella fixation was observed from the beginning of the disease. During the 1st week of the disease this reaction was strictly specific and accompanied by a decrease in the fixation of staphylococci, but later the reaction became relatively specific. An increase in Shigella fixation occurred considerably earlier than immune antibody formation, as revealed by the indirect hemagglutination test. This research substantiates the possibility of an earlier immunological diagnosis of dysentery as compared with the serological methods. 相似文献
6.
In 2,436 fecal samples and 1,272 urinary samples taken from 633 patients with dysentery caused by S. flexneri, S. newcastle and S. sonnei, Shigella antigens were detected by means of the passive hemagglutination test with antibody diagnostic agents and the antibody neutralization test. The antigen-binding activity of shigellae in urine dynamically increased in the course of dysentery. The comparison of the parallel results of both serological tests made it possible to evaluate the dispersion of the released antigen: it dynamically increased in the course of the disease, this increase being particularly high in feces. The dispersion of Shigella antigens in urine was greater than in feces over the entire course of the disease. These regularities in the release of the antigens and especially the specific features of the serological tests determined the scheme of the serological diagnosis of dysentery by the indication of Shigella antigens. 相似文献
7.
Possible mechanisms underlying the slow lactose fermentation phenotype in Shigella spp. 总被引:2,自引:0,他引:2 下载免费PDF全文
A Southern hybridization analysis revealed that the region homologous to Escherichia coli lacZ was present on the chromosomal DNAs of beta-galactosidase-positive Shigella strains, such as Shigella dysenteriae serovar 1 and Shigella sonnei strains, whereas this region was absent from chromosomal DNAs of beta-galactosidase-negative strains of Shigella flexneri and Shigella boydii. We found that the lacY-A region was deficient in S. dysenteriae serovar 1 and believe that this is the reason for the slow fermentation of lactose by this strain. S. sonnei strains possessed the region which hybridized with E. coli lacY-A despite their slow hydrolysis of lactose. The whole lactose-fermenting region was cloned from S. sonnei and compared with the cloned lac operon of E. coli K-12. Both clones directed the synthesis of beta-galactosidase in an E. coli K-12 strain lacking indigenous beta-galactosidase activity (strain JM109-1), and we observed no difference in the expression of beta-galactosidase activity in S. sonnei and E. coli. However, E. coli JM109-1 harboring the lactose-fermenting genes of S. sonnei exhibited the slow lactose fermentation phenotype like the parental strain. S. sonnei strains had no detectable lactose permease activities. E. coli JM109-1 harboring the lactose-fermenting genes of S. sonnei had a detectable permease activity, possibly because of the multicopy nature of the cloned genes, but this permease activity was much lower than that of strain JM109-1 harboring the lac operon of E. coli K-12. From these results we concluded that slow lactose fermentation by S. sonnei is due to weak lactose permease activity. 相似文献
8.
R S Shershevskaia 《Antibiotiki》1979,24(6):458-460
The dynamics of the changes in the Shigella sensitivity to gentamicin and cephaloridin was studied in vitro using liquid nutrient media with gradually increasing concentrations of the drugs. 50 passages were performed. It was found that Shigella flexner and sonnei decreased their sensitivity to gentamicin to a little extent and remained middle sensitive. Sensitivity of Shigella flexner to cephaloridin also changed to a little extent, while Shigella sonnei became moderately resistant. 相似文献
9.
H Ito N Kido Y Arakawa M Ohta T Sugiyama N Kato 《Applied and environmental microbiology》1991,57(10):2912-2917
A Southern hybridization analysis revealed that the region homologous to Escherichia coli lacZ was present on the chromosomal DNAs of beta-galactosidase-positive Shigella strains, such as Shigella dysenteriae serovar 1 and Shigella sonnei strains, whereas this region was absent from chromosomal DNAs of beta-galactosidase-negative strains of Shigella flexneri and Shigella boydii. We found that the lacY-A region was deficient in S. dysenteriae serovar 1 and believe that this is the reason for the slow fermentation of lactose by this strain. S. sonnei strains possessed the region which hybridized with E. coli lacY-A despite their slow hydrolysis of lactose. The whole lactose-fermenting region was cloned from S. sonnei and compared with the cloned lac operon of E. coli K-12. Both clones directed the synthesis of beta-galactosidase in an E. coli K-12 strain lacking indigenous beta-galactosidase activity (strain JM109-1), and we observed no difference in the expression of beta-galactosidase activity in S. sonnei and E. coli. However, E. coli JM109-1 harboring the lactose-fermenting genes of S. sonnei exhibited the slow lactose fermentation phenotype like the parental strain. S. sonnei strains had no detectable lactose permease activities. E. coli JM109-1 harboring the lactose-fermenting genes of S. sonnei had a detectable permease activity, possibly because of the multicopy nature of the cloned genes, but this permease activity was much lower than that of strain JM109-1 harboring the lac operon of E. coli K-12. From these results we concluded that slow lactose fermentation by S. sonnei is due to weak lactose permease activity. 相似文献
10.
A V Tregub I V Rubtsov A F Etkin 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1983,(9):110-113
The parameters of the assay based on the quantitative evaluation of the neutralization of specific antibodies by the antigen under study and the subsequent detection of free antibodies on the fixed reference antigen with the aim of the quantitative determination of the specific O-antigens of Salmonella, groups D, B, C1, as well as those of Shigella sonnei and Shigella flexneri, have been developed. The proposed method makes it possible to detect the O-antigen of the causative agent at concentrations of 0.001 micrograms/ml to 100 micrograms/ml. 相似文献
11.
目的:对目前最常用的检测微小RNA(miRNA)的茎环实时定量PCR法和PAP实时定量PCR法进行比较。方法:分别用茎环实时定量PCR法和PAP实时定量PCR法检测人乳腺癌细胞MCF-7中U6和23种miRNA的表达,利用定量PCR分析软件和琼脂糖凝胶电泳方法,将2种方法在引物设计难度、特异性与灵敏度,以及检测通量方面进行比较。结果:茎环法的特异性和灵敏度比PAP法高,但引物设计难度大,检测通量低;PAP法引物设计难度较低,检测通量较高,但特异性和灵敏度较差。结论:茎环法实时定量PCR适于有针对性地检测小规模miRNA,而PAP法则适于大规模miRNA筛选实验。 相似文献
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13.
A S Kariagina V G Lunin I M Gruber V M Poliachenko I I Nikol'skaia 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1987,(12):26-29
The inverse dependence of activity of restriction endonuclease SsoII preparations on the number of low molecular mass plasmids of Shigella sonnei transforming Escherichia coli recipient cells producing the enzyme has been shown. Escherichia coli strain producing efficiently one of two Shigella sonnei 47 restriction endonucleases SsoII has been isolated. The producer strain harbours two of the nine Shigella sonnei 47 plasmids. One of them P4 codes for SsoII+ phenotype while the other P9 determines the plasmids conjugation transfer. Biochemical and physiological characteristics of the producer strain XS13 are identical to the ones of the recipient Escherichia coli strain PS200. XS13 is unable to induce keratoconjunctivitis in guinea pigs in pathogenicity test. 相似文献
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15.
Arylamine N-acetyltransferase (NAT) activities with 2-aminofluorene (2-AF) as substrates were determined in Shigella sonnei (group D) collected from patients with diarrhoeal disease. The NAT activity was determined using an acetyl CoA recycling assay and high pressure liquid chromatography. Inhibition of growth studies from S. sonnei (group D) demonstrated that caffeic acid (CA), chlorogenic acid (CGA) and ferulic acid (FA) elicited a dose-dependent bactericidal effect in S. sonnei (group D) cultures, i.e. the greater the concentration of CA, CGA and FA, the greater the inhibition of growth of S. sonnei (group D). Cytosols or suspensions of S. sonnei (group D) with and without selected concentrations of CA, CGA and FA co-treatment showed different percentages of 2-AF acetylation. The data indicated that there was reduced NAT activity associated with increased CA, CGA and FA in Shigella dysenteriae (group D) cytosols and intact cells. For the cytosol and intact bacteria examinations, the apparent values of K(m) and Vmax decreased after being co-treated with 400 microM CA, CGA and FA. This report is the first demonstration of plant phenolic inhibition (CA, CGA and FA) of arylamine NAT activity and growth in the bacterium S. sonnei (group D). 相似文献
16.
I I Nikol'skaia M I Tediashvili T G Chanishvili S S Debov 《Biokhimii?a (Moscow, Russia)》1978,43(7):1228-1232
The nature and content of minor bases in DNA of 3 Shigella strains are investigated. DNAs from Shigella stutzeri 2, Sh. sonnei 1188 and Sh. sonnei 311 are found to contain 0.43, 0.56 and 0.45 mol.% of N6-methyladenine respectively. 5-methylcytosine (0.16 mol.%) is discovered in Sh. sonnei 311. Substrate specificity of adenine methylase from Sh. sonnei 1188 with respect to phage DNAs of different host modification is investigated. Recognition sites for guanine methylase of DDVI phage and for adenine methylase of Sh. sonnei 1188 turned to be different. DNA of DDII phage grown in Sh. stutzeri 2 cells does not accept methyl groups under the treatment with Sh. sonnei 1188 extracts, but it is methylated by Escherichia coli extract. Adenine methylases of Sh. sonnei 1188 and Sh. stutzeri 2 are suggested to be either the same enzyme, or enzymes, which recognition sites are partially overlapped. 相似文献
17.
Possible applications of various column chromatography techniques and isoelectrofocusing for the study of DNA-methylases of Shigella sonnei 47 cells were analyzed. A simple, rapid and convenient procedure based on the use of cation-exchange chromatography was developed for obtaining a highly active total preparation of methylases. Affinity chromatography on heparin-Sepharose was shown to be a promising approach for separating methylases according to their specificity towards nitrous bases. Isoelectrofocusing was used to identify in Shigella sonnei 47 cells six individual methylating enzymes differing in their pI values. Under the stipulation that Shigella sonnei 47 DNA-methylases show a tendency to aggregate in the course of fractionation, column chromatography is of little or no use in isolating and purifying individual methylating enzymes of the given strain. The advantages of the isoelectrofocusing technique and its utility in the study of different molecular forms of site-specific enzymes are discussed. 相似文献
18.
19.
B K Erkinbekova B V Karal'nik A I Aleshin N M Nurkina 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1992,(5-6):21-24
Shigella antigens can be detected in the excreta of convalescents after dysentery for a long time. Most frequently these antigens occur in feces, less frequently in urine and rarely in saliva. According to indirect data, S. flexneri 1-6 antigens can be detected in excreta for a longer period after convalescence than S. sonnei antigens. When antigen indication is used for the diagnosis of dysentery and epidemiological analysis is carried out, one should bear in mind the length of the agent persistence in the body, related to Shigella type. 相似文献
20.
Significance of determination of Shigella antibiotic resistance in bacteriological diagnosis of dysentery] 总被引:1,自引:0,他引:1
I V Novokshonova O I Zelenskaia I E Gol'dberg B A Kozlikhin L V Shne?derman 《Antibiotiki i khimioterapii͡a》2005,50(2-3):30-32
The results of the Shigella antibiotic susceptibility assay within 1995-2002 are presented. 1472 cultures from 1158 patients with intestinal infections and bacteria carriers were isolated. The isolates were tested for their susceptibility to tetracycline, chloramphenicol, gentamicin, kanamycin, ampicillin and ofloxacin. It was shown that S. flexneri and S. sonnei were resistant to tetracycline. The S. flexneri isolates were highly resistant to chloramphenicol (73.3 to 96.0%) while resistance to it in the isolates of S. sonnei varied from 7.7 to 88.5%. In this connection the Levin medium with tetracycline was used to increase the Shigella isolation. In the study of the culture media efficiency with respect to isolation of Shigella it was observed that the Levin medium with tetracycline provided higher rates of S. flexneri and S. sonnei isolation (2.3- and 1.7-fold increase respectively) vs. the Shigella isolation on the Ploskirev medium without the antibiotic. 相似文献