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1.
It was shown by immunodiffusion methods that nontypespecific antigens revealed in the HCl extracts of streptococcus, group A, were localized in the cell wall. In B, E, H, K, L, M, P, S, T streptococci groups there was revealed only one, and in C and G streptococci groups--two antigens identical to the HTC antigens of streptococci, group A. Besides, an antigen, which was apparently specific specific for group A streptococcus only, was detected. The data obtained should be taken into consideration in the elaboration of improved method of grouping and typing group A streptococcus.  相似文献   

2.
F fractions, obtained by the extraction of cultures of group A streptococci with distilled water at different pH, were studied by immunodifusion methods and subjected to chemical analysis. F fractions were shown to contain polyglcerophosphate, antigen E4 and in some cases group polysaccharide. Besides, F fractions were found to contain an antigen insensitive to trypsin and identical to one of the antigens of the thermostable fraction, as well as an antigen sensitive to the action of proteolytic enzymes and common to various types of group A streptococci. The antigen sensitive to the action of proteolytic enzymes were identical to one of the antigens showing no type specificity and contained in HC1 extracts prepared from group A streptococci. In grouping and typing group A streptococci the present of some F fraction antigens unrelated either to polysaccharide or to M substance should be taken into consideration. The antigens of F fraction have no protective properties.  相似文献   

3.
Composition and properties of a group A streptococcal teichoic acid   总被引:14,自引:0,他引:14       下载免费PDF全文
Teichoic acid-like material extracted by cold trichloroacetic acid from lyophilized whole cells of streptococci from groups A,D,E,O, and T was shown to give a positive precipitin reaction with group antisera. Similar material from cells of groups B,C,F,G,H,K,L,M,N,P,Q,R, and S did not give a positive reaction with group antisera. The group A material also reacted with anti-E serum; however, the opposite did not occur. A similar result was also obtained on the group T material and anti-O serum. The group A teichoic acid was purified by Sephadex column chromatography, and was shown to be free of cell wall peptidoglycan and polysaccharide, and ribitol teichoic acid. It was composed of glycerol, phosphate, alanine, and glucosamine. Alkaline hydrolysis showed the presence of ester-linked alanine and glucosaminylglycerol. Phosphorus was released from ester linkage by alkaline phosphatase. N-acetylglucosamine produced a 72% inhibition of the precipitin test at a level of 10 mumoles, and d-alanine methyl ester was significantly stronger than the l-alanine ester. A single precipitin band was seen with group A serum. The data indicate that teichoic acid of group A streptococci is a polymer composed of glycerol phosphate and containing N-acetylglucosamine and alanine. Antisera to these streptococci contain antibodies specific for the alanine and the glucosamine linkages. The use of serum containing antibodies to alanine-polyglycerophosphate shows that the occurrence of this type of teichoic acid is widespread among the streptococci.  相似文献   

4.
Pyogenic streptococci isolated from outbreaks and from sporadic infections in pigs and piglets were characterized by the almost unique combination of the properties of -haemolysis on horse blood agar and acid production from inulin. Three new serological groups were recognized, each with a single antigen different from those of any of the Lancefield groups. These antigens are polysaccharides located in the cell wall. About half the number of haemolytic streptococcal strains isolated from pigs were group R or group S streptococci, a few strains were group T streptococci, and the remaining strains were group L streptococci,S. equisimilis, group E streptococci, or group P streptococci, in this order of frequency. Only one out of about 150 haemolytic strains could not be identified serologically. Group R and group T streptococci differ from group S streptococci by acid production from raffinose. Infections with group R streptococci appeared to occur independently of age, whereas infections with group S streptococci were almost entirely confined to piglets.  相似文献   

5.
An improved method of using fluorescein-labeled antibody for the detection of polysaccharide, protein, and teichoic acid antigens synthesized by streptococcal colonies on an agar surface is described. The bacteria were grown on the surface of an agar medium contained in the shallow well of an immunodiffusion slide. An agar overlay containing the fluorescein antiserum was dispensed over the colonies, excess antiserum was washed out of the overlay agar, and the fluorescent colonies were observed under an ultraviolet microscope. The shallow well in the immunodiffusion slide prevented the agar from floating loose during washing, and the agar overlay prevented the fragmentation and loss of colonies. The thin layer of agar facilitated microscopic examination and the counting of fluorescent and nonfluorescent colonies. Colonies producing an antigen against which the antiserum was directed could readily be distinguished from colonies not producing the antigen. The specificity of the method was shown by using mixtures of streptococci representing six serological groups and five types. Those not known to possess cross-reacting antigens were specific in their reaction to the fluorescein antibody. Cross-reactions between the group antigens of A, C, and G, as reported previously by fluorescent staining of streptococcal suspensions, were also seen. Group A colonies reacted weakly with fluorescent E antibody and vice versa. The extraction of this antigen with cold trichloroacetic acid indicates it was related to the teichoic acids. Colonies possessing polysaccharide, protein, and teichoic acid antigens gave equally strong fluorescent reactions. This procedure permits detection of the synthesis of antigen which could not be observed by the use of a selective medium; it also eliminates the necessity for subculture of each colony and testing by appropriate serological means. Such a technique has value for studies in classification and biochemical genetics, and should be applicable to other genera of bacteria.  相似文献   

6.
The streptococcal group A and group E cell wall polysaccharide antigens were extracted with trichloroacetic acid from the cell or cell wall and esterified with stearic acid. The stearoyl derivatives contained 5 to 8% (by weight) of the ester. Sheep or human red blood cells were sensitized with the esterified antigens and were shown to agglutinate in the presence of specific rabbit antisera. Sera from (i) children hospitalized with group A streptococcal respiratory disease and (ii) swine possessing group E streptococcal lymphadenitis were shown to possess antibody titers significantly higher than the controls. The use of the two esterified antigens as controls for each other established the specificity of the reaction in each case. The general shape of the antigen-antibody precipitin curves was not changed when the stearoyl antigens were used; however, the quantitative aspects differed markedly. Oligosaccharides which inhibit the normal antigen-antibody precipitin reaction did not inhibit the hemagglutination reaction. The adsorption of antisera with whole streptococcal cells reduced the hemagglutination titer in relation to the quantity of cells employed. Data are given on the (i) optimal concentration of stearoyl antigen for sensitization, (ii) time of adsorption of antigen to red cells, (iii) use of albumin as diluting fluid, and (iv) condition of red cells. Properties of the esterified antigens and the mechanism of the agglutination reaction are discussed. The results indicate that polysaccharide antigens of other bacteria may be esterified and employed in a similar manner.  相似文献   

7.
Eleven Streptococcus group E strains, representing serotypes I, II, III, IV, V, and "untypable" isolates, were extracted by formamide, trichloroacetic acid, and hydrochloric acid under various conditions in an effort to determine the best method for recovering maximum amounts of group and type antigens. The group antigen was found to be relatively stable, and adequate amounts for identification purposes were recovered by a wide spectrum of conditions. Type-specific antigens were relatively labile, and were destroyed at low pH in acid hydrolysis or by prolonged heating in formamide hydrolysis. The best single procedure for recovering both type and group antigens from Streptococcus group E was formamide hydrolysis for 30 min at 180 C.  相似文献   

8.
To determine the cellular distribution of Toxoplasma antigens, RH strain tachyzoites were incubated with either one of three monoclonal antibodies (FMC 19, FMC 20, FMC 22) to T. gondii, or one of two controls (the murine myeloma protein MOPC 21, or phosphate buffered saline), and then incubated with peroxidase-labelled goat-antimouse IgG. Diaminobenzidine was added as substrate and electron microscopy was used to localize the reaction. All three antibodies bound to the entire periphery of the tachyzoite surface membrane. To ascertain the chemical composition of the antigens against which seven monoclonal antibodies (FMC 18, FMC 19, FMC 20, FMC 22, FMC 23, 2G11, 3E6) to T. gondii reacted, untreated, pronase-treated, or periodate-treated tachyzoites were incubated with the antibodies or MOPC 21, and then with [125I]-Protein A. The pronase-treated tachyzoites showed reduced binding for six of the antibodies, compared with the reduction in binding of MOPC 21 with the pronase-treated parasites. The periodate-treated tachyzoites had reduced binding for FMC 18 only. The results of these experiments confirm that most Toxoplasma surface antigens are protein in nature, and are consistent with the hypothesis that at least one cytoplasmic antigen is secreted onto the parasite cell surface.  相似文献   

9.
The role of the type-nonspecific (TNS) cell-wall antigens of group A streptococci has been determined. The study has been made on guinea pigs sensitized with whole microbial cells or HCl extracts containing TNS antigens. To determine delayed hypersensitivity, the in vitro cytotoxic test on adhering lymph-node cells in the autologous system has been used. The study has shown that sensitization with group A streptococci of different types or with TNS antigens induces the development of delayed hypersensitivity to TNS antigens (or antigen), common for different types of group A streptococci, but specific for this group. HCl extracts containing TNS antigens can be recommended as the preparation for testing delayed hypersensitivity to antigens, specific for group A streptococci.  相似文献   

10.
Summary Detailed information concerning the performing and the reading of theCamp reaction is given in this study. ComparableCamp reactions were carried out on 1223 human streptococcals strains. Group B strains reacted positive in 99.5%++94%,+in 5% and ±in 0.5%. Group A strains were positive in about 80%; ++ in 30%, +in 28% and ±in 22%. The reactions in the A group were often incomplete. There are reasons to suppose that the responsible agents in the two groups of streptococci are not quite identical. C and G group streptococci both reacted positive in only 0.5%; all tested F and ungrouped strains were negative. By adding theCamp reaction to simple bacteriological methods it is possible to recognize with certainty human group B streptococci. Some observations were made over the interaction of both components of the reaction, the β toxin and the lytic agent produced by B group streptococci (Camp factor). Preliminary chemical studies make it likely that the Camp factor has a polypeptidic structure. Aided by a grant from the National Health Research Councils T.N.O.  相似文献   

11.
Abstract The ability of haemolytic streptococci to produce NAD+-glycohydrolase was investigated by a fluorescent assay. Enzyme production was found in 31 (91%) of 34 group A, 17 (61%) of 28 group C and eight (27%) of 30 group G isolates. The high producers were found in 22 (65%) of group A, one (4%) of group C and none of group G isolates. The high producers of the group A isolates belonged to T-1, T-3, T-4 or T-12 serotype. These results suggest that NAD+-glycohydrolase productivity of streptococci is closely related to specific Lancefield's groups or T serotypes.  相似文献   

12.
The adenovirus E1A transforming region, which encodes immortalization, partial cell transformation, and gene activation functions, expresses two early mRNAs, 13S and 12S. Multiple-T antigen species with different electrophoretic mobilities are formed from each mRNA, presumably by unknown posttranslational modifications. The adenovirus type 12 (Ad12) 13S and 12S mRNAs encode E1A T antigens of 266 and 235 amino acid residues (266R and 235R), respectively. To study possible posttranslational processing at the N and C termini and to distinguish between the Ad12 266R and 235R T antigens, we prepared antibodies targeted to synthetic peptides encoded at the common C (peptide 204) and N (peptide 202) termini of the 266R and 235R T antigens and at the unique internal domain of the 266R T antigen (peptide 206). The specificity of each anti-peptide antibody was confirmed by immunoprecipitation of the 266R and 235R T antigens produced in Escherichia coli. Immunoprecipitation analysis of the E1A T antigens synthesized in Ad12-infected KB cells revealed the following. Antibody to the common C terminus recognized three T antigens with apparent Mrs of 43,000, 42,000, and 39,000 (43K, 42K, and 39K). All three forms were phosphorylated and were present in both the nucleus and the cytoplasm. The 43K and 42K T antigens were rapidly synthesized during a 10-min pulse with [35S]methionine in Ad12-infected cells. The 43K T antigen had a half-life of 20 min, the 42K T antigen had a longer half-life of about 40 min, and the 39K T antigen became the predominant E1A T antigen. Antibodies to the unique region immunoprecipitated the 43K T antigen but not the 42K and 39K T antigens. Antibody to the N terminus immunoprecipitated the 43K and 42K T antigens but not the 39K T antigen, suggesting that the 39K T antigen possessed a modified N terminus. Partial N-terminal amino acid sequence analysis showed that the 43K and 42K T antigens contain methionine at residues 1 and 5, as predicted from the DNA sequence, whereas no methionine was released from the 39K T antigen during the first six cycles of Edman degradation. We propose that the short-lived 43K T antigen is the primary product of the 13S mRNA, the 266R T antigen; the somewhat more stable 42K T antigen is the primary product of the 12S mRNA, the 235R T antigen.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

13.
The tumor (T) antigens encoded by the human adenovirus early transforming region 1A (E1A) are gene regulatory proteins whose functions can immortalize cells. We have recently described the synthesis in Escherichia coli and the purification of the complete T antigens encoded by the adenovirus type 12 (Ad12) E1A 12S mRNA (235-residue [235R] T antigen) and 13S mRNA (266R T antigen). In this study, we show that the Ad12 E1A T antigens are extensively phosphorylated in Ad12-infected mammalian cells but are not phosphorylated in E. coli. Inasmuch as posttranslational phosphorylation at specific amino acid sites may be important for biological activity, we have studied the phosphorylation of the E. coli-produced T antigens in vitro by using a kinase activity isolated from cultured human KB cells. The kinase was purified about 300-fold and appears to be a cyclic AMP-independent, Ca2+-independent protein kinase requiring only ATP and Mg2+ for activity. To determine which amino acids are phosphorylated and whether phosphorylation in vitro occurs at the same amino acid sites that are phosphorylated in vivo, the Ad12 E1A T-antigen species synthesized by infected cells were metabolically labeled with 32Pi and compared with the E. coli-produced E1A T antigens labeled in vitro with [gamma-32P]ATP by using the partially purified kinase. Partial V8 proteolysis analysis gave similar patterns for in vivo- and in vitro-phosphorylated T antigen. Two-dimensional maps of tryptic phosphopeptides and of chymotryptic phosphopeptides suggested that mainly the same amino acid sites are phosphorylated in vitro and in vivo and that phosphorylation occurred at multiple sites distributed throughout the T-antigen molecule. Serine was the only amino acid that was phosphorylated both in vivo and in vitro, and, surprisingly, most serines appeared to be phosphorylated. The feasibility of faithfully phosphorylating T antigens in vitro suggests that the E. coli-produced Ad12 E1A 235R and 266R T antigens may prove useful for molecular studies on T-antigen function.  相似文献   

14.
Polysaccharides extracted from Z3III streptococci either with formamide or with dilute hydrochloric acid or isolated from the growth medium could be fractionated in type III- and group Z3 antigens by alcohol precipitation. No good separation could be obtained from TCA extracts. When the same extractions and fractionations were applied to streptococci carrying type III antigen, but different group antigens, good separations were again obtained of all formamide extracts, but not of all hydrochloric acid extracts. The group antigens showed a rhamnose content of at least 50% and contained hexosamines. Type III antigens contained mainly rhamnose, glucose and galactose in relative amounts of approximately 1:2:3. Analysis of the methylated type III antigen suggests it to be a polysaccharide with a linear structure. Type III antigen isolated from the medium was characterized not only by a different sugar ratio, but also by its fucose content of 20%. In some cases the purified polysaccharides contained considerable amounts of glycogen-like material. Partial acid hydrolysis of the type III antigen extracted with formamide yielded a great number of oligosaccharides. Analyses, inhibition reactions and methylation studies gave indications that the most probable structure of a determinant group of type III antigen is β-glucosyl-(1-6)-galactosyl-(1-6)-galactosyl-(1-3)-rhamnose. The possibility of the existence of a second determinant group is discussed.  相似文献   

15.
Extemporaneous coagglutination procedure for the serological grouping of beta-hemolytic streptococci is reported. Streptococcal group antigens were extracted with nitrous acid. 250 strains of groups A, B, C, F and G streptococci were tested with this method. An agreement of 100% was found between this method and the Lancefield capillary precipitation procedure. Extemporaneous coagglutination method was found to be rapid, reliable, easy and economical and could be adopted in any routine diagnostic laboratory.  相似文献   

16.
Abstract Genetic diversity of the streptokinase gene ( sk ) from 36 strains of S. equisimilis and 54 strains of group G streptococci was examined. The strains were isolated from patients with various streptococcal disease manifestations and healthy carriers. The region of the gene that corresponds to amino acid residues 174–244, was PCR amplified. The amplified product was subjected to Mlu I, Pvu II, Dra I and Dde I digestion. Based on the restriction enzyme digestion patterns nine sk alleles were recognized. There was no correlation between the various sk gene alleles and streptococcal disease manifestations. Three of the nine sk gene alleles, sk 4, sk 7, and sk 8, were detected earlier among group A streptococci. The other six alleles were unique to S. equisimilis and group G streptococci. The most common alleles were sk 5, found in 21/90 (23%) and sk 10 detected in 43/90 (47%) of the strains. Alleles sk 1 and sk 2, the most frequent among group A streptococci, were not found among the strains in the present investigation. Thus, it appears that the sk gene has been evolving in line with other species distinguishing features of the streptococci.  相似文献   

17.
The lymphoblasts from 100 patients with acute lymphocytic leukaemia were investigated for the expression of receptors for sheep erythrocytes (E) and of a specific heterologous T cell antigen (T). In 17 cases, both T cell markers were expressed simultaneously on the leukaemic cells. In 13 cases only T antigens could be demonstrated on the lymphoblasts. A quantitative analysis of T antigens by immunoautoradiography revealed that the T expression of E-T+ -lymphoblasts was in general like that of E+T+-lymphocytes in the blood of normal persons, in several cases even higher. Therefore, the failure of E-rosette formation cannot be correlated to a decrease of the other T cell differentiation marker. In 7 out of 9 tested cases, a strong acid phosphatase reaction product located paranuclearly could be demonstrated. Complement-receptors were expressed in 3 of 5 cases which were also demonstrated in some cases of the E+T+-ALL group. The latter group was characterized by a T antigen expression like that of thymocytes. 4 cases of the E-T+ALL group were adults. Since the leukaemia cells of 2 cases were negative for acid phosphatase, PAS and all surface markers including cALL antigen, the T antigen can classify undifferentiated and otherwise unclassificable leukaemias. The clinical signigicance of the E-T+-ALL seems to be important since 5 out of 9 children with this type of ALL died soon after diagnosis.  相似文献   

18.
On typing of 90 strains of bovine Group-B streptococci (B-str.) from 21 herds, NT1, NT2 and NT3 antigens were found in 30 %, viz., NT1 in 14.4 %, NT2 in 3.3 %, and NT3 in 12.2 %. In 9 of the 21 herds examined (43 %) one or other of these antigens was found. Among 8 strains from 4 herds of Herd type NT the NT1 antigen was demonstrated once. In 5 herds of Herd type X, 20 strains were typed, and 9 isolates (45 %) from 3 herds (60 %) carried one or other of the three antigens. Among herds in which the herd type was referable to polysaccharide antigens of the accepted set, NT3 antigen was present in 1 herd of Herd type Ia, namely along with IaX antigens in two strains, and with Ia antigen in one. In 3 herds of Herd type Ibc and in 2 herds of Herd type Ib no NT1, NT2, or NT3 antigen was demonstrated. On the other hand, such antigens were found in all of 4 herds of Herd type III, being present in 50 % of the strains (14/28) examined, and the frequency of NT1, NT2, and NT3 antigens was only slightly higher among NT and X strains (10/19 or 53 %) than among III and IIIX strains (4/9 or 44 %). The NT2 reference strain carried the Ibc protein antigen. In addition to strong homologous reactions, NT1 antiserum reacted with B-str. group antigen, NT2 antiserum with Ibc antigen, and NT3 antiserum with the NT1 reference strain. It is concluded that the NT1, NT2, and NT3 antigens are of doubtful value in epidemiological studies on bovine infections with group-B streptococci.  相似文献   

19.
A simple and rapid procedure for the isolation in high yield (about a 30% recovery based on the total 30 to 60% ammonium sulfate recovery) of homogeneous purified group A streptococcal M-protein is described. M-proteins extracted from whole cells of group A streptococci by treatment with hot HCl were neutralized, fractionated with ammonium sulfate, dialyzed, lyophilized, and then subjected to treatment with hot 60% trichloroacetic acid. This was shown to produce an M-protein preparation, free of group A carbohydrate activity and extraneous antigens, in yields up to 10-fold higher than previous methods in about one-fifth the time. These M-protein preparations were shown to: (i) have similar amino acid compositions to their respective type-specific proteins purified by diethylaminoethyl and O-(carboxymethyl) cellulose chromatography, (ii) react with their respective type-specific antisera in Ouchterlony diffusion, (iii) produce antisera in rabbits capable of promoting streptococcal long-chain formation in vitro, and (iv) give only one major band on polyacrylamide gel disk electrophoresis. The data allow for an explanation of the hitherto described multiple banding M-proteins seen on acrylamide electrophoresis.  相似文献   

20.
Hydrochloride extracts obtained from group B streptococcal strains of different serotypes have proved to be the source of type-nonspecific protein antigens, precipitated with ethanol and studied by gel chromatography and spectrophotometric scanning in ultraviolet rays. Thus, 2 or 3 antigens, one of them found to be common for streptococci of groups A, B and G, as well as the admixture of group-specific polysaccharide, have been detected. In extracts obtained from group B streptococcal strains of different serotypes a common protein antigen, specific only for group B, has been detected. The suitability of gel chromatography with the use Toyopearl gel HW-55F for the preparative isolation of the specific fraction of protein type-nonspecific antigen with a view to the subsequent study of immune response to group B streptococci has been shown.  相似文献   

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