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1.
The presence and quantity of protein A in Staphylococcus hyicus subsp. hyicus isolates were examined by an enzyme-linked immunosorbent assay (ELISA) and immunoelectron microscopy. Cell-bound protein A was demonstrated in 45 (94%) of 48 isolates from diseased pigs and in 113 (86%) of 132 isolates from healthy pigs by ELISA using peroxidase-conjugated rabbit antibody, but was not found in isolates from chickens and cows. Most of these swine isolates contained about 100 to 300 ng of cell-bound protein A/ml. Extracellular protein A was not detected in any isolates from pigs, chickens or cows. In the immunoelectron microscopy assay, swine isolates were labeled with goat anti-mouse IgG conjugated to colloidal gold particles, but chicken and cow isolates were not labeled.  相似文献   

2.
Staphylococcus hyicus is considered to be an etiological agent of exudative epidermitis in young pigs, but is frequently isolated from chickens and cows. In the present study, the proteases of 58 S. hyicus isolates from pigs, chickens and cows were examined by skim milk agar plate culture, gelatinolytic zymogram and polymerase chain reaction (PCR). These isolates showed proteolytic activity on skim milk agar plate, but activity differed amongst the isolates. In the gelatinolytic zymogram, one main band was observed in all the porcine, avian and bovine isolates, while one to two other bands were recognized in some isolates. The formation of the main band was inhibited by EDTA, suggesting that this protease is a metalloprotease. When the Shp1 gene, which codes for one the metalloproteases of S. hyicus as reported previously, was examined by PCR, one band arising from an open reading frame (ORF) was detected in all of 58 isolates tested. In addition, upstream nucleotides containing the promoter region of Shp1 gene were amplified and sequenced. From these results, it seems likely that the metalloprotease is common to porcine, avian and bovine isolates of S. hyicus.  相似文献   

3.
Lysogeny was readily demonstrated among strains of Staphylococcus hyicus that were isolated from chickens. Susceptibility to phage lysis was affected by prophage immunity, but lipase activity and erythromycin resistance were not affected by the presence of temperate phage. In contrast to previously published results, lipase-negative strains of S. hyicus were relatively common and the use of selective media based on lipase activity would have been unsuitable for detection of the S. hyicus strains examined.  相似文献   

4.
In the present study, previously characterized Staphylococcus hyicus isolated in Russia (n=23) and Germany (n=17) were investigated for the prevalence of the exfoliative toxin encoding genes exhA, exhB, exhC and exhD by multiplex PCR resulting in the detection of exhD positive strains among the S. hyicus isolated from pigs with exudative epidermitis in Russia and the detection of exhC and exhD for one and two strains isolated from exudative epidermitis in Germany respectively. The toxin gene negative strains were generally isolated from apparently healthy pigs, from other animals and from specimens where the relation between the isolation of S. hyicus and the clinical symptoms remained unclear. Partial sequencing of the toxin genes of selected exhC and exhD positive strains and comparing the sequencing results with sequences of exhC and exhD reference strains revealed an almost complete identity. The results of the present study were in agreement with the findings of Andresen and Ahrens (J. Appl. Microbiol., 96, 2004, 1265) and Andresen (J. Vet. Rec., 157, 2005, 376) that the presented multiplex PCR could be used to investigate S. hyicus for toxinogenic potential and that there is an association between the presence of toxin genes in S. hyicus strains from exudative epidermitis. However, comparable with the S. hyicus strains isolated in Germany which were investigated previously by Andresen (J. Vet. Rec., 157, 2005, 376), exhD seems to predominate in S. hyicus strains from Russia.  相似文献   

5.
Four phages were isolated and used for typing Staphylococcus hyicus subsp hyicus isolated from pigs with or without exudative epidermatitis (EE) in Japan. Sixty-four (85.3%) of the 75 isolates examined were typeable at either routine test dilution (RTD) or 100 X RTD. Two or more kinds of phage patterns were present in the isolates from each pig with EE. All isolates from healthy pigs showed a single-phage pattern. Fourteen (32.6%) of 43 isolates and 7 (87.5%) of 8 isolates from pigs with EE in Belgium and Czechoslovakia, respectively, were typeable with the 4 phages. None of 180 isolates of S aureus, 7 (6.4%) of 110 isolates of S intermedius, and 2 (2.3%) of 86 isolates of S epidermidis were typeable.  相似文献   

6.
A total of 218 isolates of Staphylococcus hyicus from pigs in eight countries (Belgium, Croatia, Germany, Japan, Korea, Slovenia, the uk and the usa) and 44 isolates from other animals in Belgium, India, Japan and the usa were examined for the genes encoding the exfoliative toxins ExhA, ExhB, ExhC and ExhD by multiplex pcr. The expression of the toxins was confirmed by immunoblot analysis, using monoclonal or polyclonal antibodies specific for each of the toxins. The porcine isolates were from pigs with exudative epidermitis, pigs with other lesions and from healthy pigs, and one or more of the toxins could be found among the isolates from the pigs in all the countries. Toxigenic strains of S hyicus were isolated from both healthy and diseased pigs, but the chance of isolating toxigenic strains from pigs with exudative epidermitis was greater than from pigs with other lesions or healthy pigs. Of the 44 isolates from other animal species, only one isolate, from a hare from Belgium, produced ExhB, and one isolate, from a cow with mastitis from Japan, produced ExhA.  相似文献   

7.
125-I-IgG binding activities were observed with 15 (17%) of 90 S. intermedius isolates from dogs and 39 (95%) of 41 S. hyicus isolates from pigs. Binding activities were not detected with S. hyicus isolates from cows. The IgG binding proteins of 2 S. intermedius, 2 S. hyicus, and protein A from S. aureus Cowan I were isolated from their cell surfaces. The proteins precipitated with IgG preparations from human, rabbit, pig, dog and horse, but not with IgG from cow, mouse and chicken. This indicated that these IgG binding proteins could be classified as type I receptors. In addition, the isolated proteins from all 3 staphylococcal species precipitated with polyclonal chicken anti-protein A antiserum. SDS-PAGE, Western blotting and gel isoelectric focussing of the proteins revealed numerous bands in the 42,000 D range and acid isoelectric points. The isoelectric point of the isolated proteins from both S. intermedius cultures was slightly more acidic than those from S. hyicus and S. aureus. The present results indicate a close functional and antigenic similarity, if not identity, between IgG binding proteins of S. intermedius and S. hyicus, and protein A of S. aureus.  相似文献   

8.
Multiple outbreaks of acute severe fibrinopurulent lesions of the eyelids occurred in chickens and turkeys. Lesions began as tiny foci of epidermal necrosis and ulceration and spread to involve the entire eyelid. Scabs overlying the epidermis contained large gram-positive cocci; lesser numbers of small cocci and gram-negative bacilli were in more superficial areas. Staphylococcus hyicus was isolated from birds in all stages of the disease. Escherichia coli and Streptococcus sp. were isolated only during severe stages; no anaerobic bacterial pathogens were isolated. Vasculitis and perivascular lymphocytic infiltrates in deep layers of the dermis suggested that a staphylococcal toxin may have been involved. The disease was not reproduced by scarifying S. hyicus onto the eyelids or by intravenous inoculation of retrovirus-infected chickens.  相似文献   

9.
The Staph-Zym system was evaluated as a means for identifying cultures of Staphylococcus hyicus isolated from pigs and bovines and cultures of Staphylococcus intermedius isolated from canines. The selected cultures had been identified by conventional methods. The Staph-Zym system correctly identified all 52 S. hyicus and all 33 S. intermedius. It is concluded that the Staph-Zym system is a practical and reliable test for identifying mostly animal pathogenic S. hyicus and S. intermedius, and might possibly be useful for veterinary microbiologists.  相似文献   

10.
Immunoblot analysis and enzyme-linked immunosorbent assay (ELISA) confirmed previous reports that the Staphylococcus hyicus exfoliative toxins ExhA and ExhB are metalloproteins, and further indicated that ExhC is also a metalloprotein. An indirect ELISA was developed for the detection of toxigenic strains as an alternative method to the use of phage typing for selection of S. hyicus isolates to be used in autogenous vaccine against exudative epidermitis in pigs. The indirect ELISA was evaluated by investigating the presence of toxin among a total of 655 S. hyicus isolates from 69 pig skin samples, one from each of the 69 pig herds with outbreak of exudative epidermitis. Toxigenic S. hyicus were detected in 74% of the cases by ELISA. From each of the five cases, in which initially no toxigenic S. hyicus were found, a further 40 S. hyicus-like colonies were tested in ELISA. Testing of this number of colonies has a >99% probability of disclosing toxigenic S. hyicus. Toxin-producing isolates were found in only two of the five cases investigated. This may indicate the existence of one or more variants of the exfoliative toxin of S. hyicus that are not detected in the indirect ELISA or that S. hyicus may be displaced from lesions of exudative epidermitis.  相似文献   

11.
A species specific PCR test, based on manganese-dependent superoxide dismutase A encoding gene sodA, was developed for the identification of Staphylococcus hyicus, an important bacterial pathogen in pigs. The designed primers allowed a rapid and reliable identification of phenotypically characterized S. hyicus, isolated in Russia, Germany and Denmark. No cross reactivities could be observed investigating staphylococcal reference strains representing 18 different species and subspecies. The use of the described primers might improve a future diagnosis of this bacterial pathogen.  相似文献   

12.
Culture supernatants from a number of Staphylococcus hyicus strains caused toxic effects to both murine fibroblast and porcine keratinocyte cells in culture. The extent of cytotoxicity was shown to differ between strains and may provide an indication of strain virulence. Purification of cytotoxic activity produced by S. hyicus (strain P119) using preparative isoelectric-focussing demonstrated it to be cytolytic, haemolytic and non-proteolytic. The cytotoxin demonstrates certain properties in common with the delta haemolysin of Staphylococcus aureus.  相似文献   

13.
Staphylococcus hyicus strains with different phage types, plasmid profiles, and antibiotic resistance patterns were isolated from piglets with exudative epidermitis. The strains could be divided into virulent strains, producing exudative epidermitis, and avirulent strains, producing no dermal changes when injected in experimental piglets. The results showed that both virulent and avirulent strains were present simultaneously on diseased piglets. This constitutes a diagnostic problem. Concentrated culture supernatants from nine virulent strains injected in the skin of healthy piglets produced a crusting reaction in all piglets. Acanthosis was observed in the histopathological examination of the crustaceous skin. Concentrated culture supernatants from nine avirulent strains produced no macroscopic or microscopic skin changes. Protein profiles from all virulent strains and seven out of nine avirulent strains showed a high degree of protein band homology. An approximately 30 kDa protein present in all concentrated culture supernatants capable of producing skin changes, could not be detected in samples that did not produce skin changes. No other protein showed a similar association. It is concluded that crusting reaction of piglet skin is a suitable indicator of virulence in S. hyicus in relation to exudative epidermitis, and that virulent strains produce a 30 kDa protein, absent in concentrated culture supernatants from avirulent strains. This 30 kDa protein might be an exfoliative toxin.  相似文献   

14.
The species composition was determined in the set of 52 randomly selected strains of coagulase-negative staphylococci, which were isolated from the milk of dairy cows in 1989. Of this set of strains, the following species were identified: Staphylococcus hyicus subsp. chromogenes (26.9% strains of the set), S. hyicus subsp. hyicus (10.3%), S. xylosus (19.3%), S. saprophyticus (11.5%), S. warneri (9.6%), S. haemolyticus (9.6%), S. hominis (3.8%). Attention is drawn to the increasing occurrence and significance of coagulase-negative staphylococci from the point of view of mastitis in dairy cows.  相似文献   

15.
Exfoliative toxin was isolated from the sterile cell-free filtrate of 24 h culture of Staphylococcus hyicus subsp. hyicus strain P-1. The partial purification of exfoliative toxin produced by S. hyicus (shET) was performed by precipitation with 50-80% saturated ammonium sulfate, gel filtration on a Sephadex G-75 column and column chromatography on DEAE-cellulose. Partially purified shET (pp-shET) caused exfoliation in piglets at 8 to 12 h after intradermal or subcutaneous injection. However, heat-treated pp-shET did not cause exfoliation in piglets for up to 24 h after injection. On histopathological examination of the skin at 12 h after injection of pp-shET, an intraepidermal cleavage plane was shown between the stratum corneum and stratum granulosum and at the stratum granulosum.  相似文献   

16.
根据GenBank已发表的猪葡萄球菌的6种脱落毒素基因序列,设计合成了6对相应的特异性引物,通过特异性、敏感性和重复性试验建立了可行的多重PCR检测方法。用该方法对临床分离到的9株猪葡萄球菌进行检测,均扩增出了与预期大小相符的23SrDNA（662bp）条带;同时,其中6株分别扩增出了EXHA（316bp,2株）、EXHC（525bp,2株）和Shet-A（814bp,2株）基因特异性条带;另外3株均未扩增出任何毒素基因特异性条带,鉴定为无毒力菌株,以上结果与生化鉴定及单一PCR检测测序结果一致。结果表明,本试验所建立的多重PCR方法不仅操作快速方便、节约试验成本,而且具有高度特异性、敏感性和良好的重复性,可用于仔猪渗出性皮炎的诊断和猪葡萄球菌的快速鉴定。  相似文献   

17.
Identification to species level was attempted on a collection of 954 cultures of catalase-positive, clumping-factor- and beta-haemolysin-negative Gram-positive cocci isolated from teats and milk of cows. Eighty-seven per cent of the strains were identified as Staphylococcus xylosus, S epidermidis, S sciuri, S haemolyticus, S hyicus subsp hyicus and chromogenes, S simulans and S cohnii. Nine per cent of the collection belonged to another group which could not be identified with any of the known Staphylococcus species. Many of the strains of this group and also part of the S epidermidis and S hyicus subsp chromogenes strains examined showed various degrees of growth enhancement on certain media when fatty substances were added. Only nine strains were classified as Micrococcus. A scheme for the identification of coagulase-negative staphylococci from cows' milk is proposed.  相似文献   

18.
An IgG-binding protein A homolog in Staphylococcus hyicus   总被引：1，自引：0，他引：1  
Shotgun phage display was used to identify a homolog of the IgG-binding protein staphylococcal protein A in Staphylococcus hyicus type strain CCUG 15602/ATCC 11249. This bacterium is the causative agent of exudative epidermitis in pigs and can also cause mastitis in cattle. A protein with similar features as the originally identified protein A in Staphylococcus aureus was described; an YSIRK-type signal peptide, four IgG-binding domains, a putative peptidoglycan-binding domain, and a cell wall anchoring motif (LPXTG) was present. The highest degree of similarity was to a protein A homolog in Staphylococcus pseudintermedius. However, typical Xr polypeptide repeats present in the protein A of S. aureus and S. pseudintermedius could not be identified in the protein A of S. hyicus. The presence of the spa gene in ten porcine and eight bovine clinical isolates of S. hyicus was investigated by PCR. In all isolates, the spa gene could be detected but the amplicons were of two sizes. Sequence analysis of four selected PCR amplicons showed that only three IgG-binding domains were present in the protein A of clinical isolates generating a smaller spa fragment. The finding of spa in S. hyicus contributes to an increased understanding of potential virulence factors in this species.  相似文献   

19.
为分析猪葡萄球菌脱落毒素EXHC和SHETA基因结构并预测其所编码蛋白的结构和功能,本试验根据GenBank已报道的猪葡萄球菌脱落毒素EXHC和SHETA基因序列分别设计了1对特异性引物,从猪葡萄球菌GDZC株中扩增获得EXHC和SHETA基因片段,大小分别为1007和971 bp。序列分析结果表明,EXHC基因与猪葡萄球菌丹麦分离株(GenBank登录号:AF515455)及猪源松鼠葡萄球菌河北分离株(GenBank登录号:JF755400)的核苷酸序列、氨基酸序列同源性均为100.0%,而与其他葡萄球菌脱落毒素基因的核苷酸、氨基酸序列同源性分别为3.3%~53.9%和7.9%~44.2%。SHETA基因与日本分离株(GenBank登录号:AB036768)的核苷酸序列同源性为96.2%,氨基酸序列同源性为98.4%,在保守区共有31个碱基发生突变。利用DNAStar软件对EXHC和SHETA蛋白结构进行分析,结果显示EXHC基因编码的蛋白为亲水性蛋白,SHETA基因编码蛋白为疏水性蛋白,抗原性较差。本研究从猪葡萄球菌GDZC株中成功扩增获得EXHC和SHETA基因片段并对其编码的蛋白结构进行了预测,证实了中国分离的猪葡萄球菌同时携带有EXHC和SHETA 2种毒素基因,为进一步研究猪葡萄球菌的致病机理及毒素之间的相互作用提供了理论依据。  相似文献   

20.
OBJECTIVE: To serotype an enterotoxin gene from Escherichia coli isolated from cows, pigs, and chickens in Korea. SAMPLE POPULATION: Isolates from 37 cows with mastitis, 51 diarrheic pigs, and 5 diarrheic chickens. PROCEDURE: Serogroups and serotypes were identified by slide agglutination testing, using pathogenic E coli sera. Detection of E coli enterotoxins by use of reversed passive latex agglutination and ELISA was compared by proving existence of the gene by polymerase chain reaction (PCR) analysis. RESULTS AND CONCLUSIONS: Detection of E. coli enterotoxin by either method was positive for 1 strain (O20:H10; heat-labile enterotoxin [LT+], heat-stable enterotoxin [STa+]; isolation rate, 2%) and 3 other strains (O111:H10, O119:H9, and O125:H6, STa+; isolation rate, 5.9%) isolated from fecal specimens obtained from diarrheic pigs. The E coli enterotoxin genes were identified by use of PCR analysis in 1 strain containing the 417- and 163-base pair (bp) genes (LT+, Sta+; O20:H10) and in 3 strains containing only the 163-bp gene (STa+; O111:H10, O119:H9, and O125:H6). CLINICAL RELEVANCE: Serotyping of E coli enterotoxin may be used to analyze patterns of transmission among species of domestic animals.  相似文献   

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