The poultry red mite,Dermanyssus gallinae,a potential vector of Erysipelothrix rhusiopathiae causing erysipelas in hens

Erysipelas is a bacterial disease caused by Erysipelothrix rhusiopathiae, which may infect swine as well as several other species of mammals and birds, including domestic fowl. In poultry, erysipelas may cause sudden high mortality due to septicemia. This communication describes the first isolation of E. rhusiopathiae from the haematophagous poultry red mite, Dermanyssus gallinae DeGeer (Acari: Dermanyssidae), that was collected on three farms where hen erysipelas was diagnosed. The bacteria were isolated from the integument as well as from the interior of the mites. Serotypes 1a and 1b of E. rhusiopathiae found in the mites corresponded with those isolated from the diseased birds. These findings imply that D. gallinae is a potential vector of E. rhusiopathiae. The current lack of effective measures to control D. gallinae causes recurring mite problems in poultry facilities once afflicted by this parasite. Consequently, mites containing E. rhusiopathiae may act as reservoir hosts of this bacterium, allowing it to persist in the poultry house between flock cycles as a source of infection for the replacement pullets. The zoonotic potentials of both E. rhusiopathiae and D. gallinae should also be considered.     

Occurrence of Erysipelothrix rhusiopathiae on pork and in pig slurry, and the distribution of specific antibodies in abattoir workers

Strains of Erysipelothrix rhusiopathiae isolated at 19 pig farms serving a certain abattoir, and on pork and in workers of this abattoir were studied. Mouse-pathogenic E. rhusiopathiae was found in pig slurry from two farms (11%). The strains belonged to serotypes 7 and 16 (both from the same farm) or were untypable. In pig slurry from the abattoir lairage only serotype 2 strains were found and all were pathogenic to mice. Mouse-pathogenic E. rhusiopathiae strains of serotype 2 were also recovered from 25 pork loins (25%). A mouse-pathogenic E. rhusiopathiae (serotype 2) strain was isolated from one of the 16 hand infections of slaughterhouse workers. The E. rhusiopathiae strains were phenotypically grouped by the API 50 CH system. Variations were demonstrated for the different serotypes. In 20 of 138 workers antibodies against E. rhusiopathiae were found; 14 had increased levels of IgG antibodies, seven had increased levels of IgM antibodies and one had an increased level of both.     

Adhesive surface proteins of Erysipelothrix rhusiopathiae bind to polystyrene,fibronectin, and type I and IV collagens

Erysipelothrix rhusiopathiae is a gram-positive bacterium that causes erysipelas in animals and erysipeloid in humans. We found two adhesive surface proteins of E. rhusiopathiae and determined the nucleotide sequences of the genes, which were colocalized and designated rspA and rspB. The two genes were present in all of the serovars of E. rhusiopathiae strains examined. The deduced RspA and RspB proteins contain the C-terminal anchoring motif, LPXTG, which is preceded by repeats of consensus amino acid sequences. The consensus sequences are composed of 78 to 92 amino acids and repeat 16 and 3 times in RspA and RspB, respectively. Adhesive surface proteins of other gram-positive bacteria, including Listeria monocytogenes adhesin-like protein, Streptococcus pyogenes protein F2 and F2-like protein, Streptococcus dysgalactiae FnBB, and Staphylococcus aureus Cna, share the same consensus repeats. Furthermore, the N-terminal regions of RspA and RspB showed characteristics of the collagen-binding domain that was described for Cna. RspA and RspB were expressed in Escherichia coli as histidine-tagged fusion proteins and purified. The recombinant proteins showed a high degree of capacity to bind to polystyrene and inhibited the binding of E. rhusiopathiae onto the abiotic surface in a dose dependent manner. In a solid-phase binding assay, both of the recombinant proteins bound to fibronectin, type I and IV collagens, indicating broad spectrum of their binding ability. It was suggested that both RspA and RspB were exposed on the cell surface of E. rhusiopathiae, as were the bacterial cells agglutinated by the anti-RspA immunoglobulin G (IgG) and anti-RspB IgG. RspA and RspB were present both in surface-antigen extracts and the culture supernatants of E. rhusiopathiae Fujisawa-SmR (serovar 1a) and SE-9 (serovar 2). The recombinant RspA, but not RspB, elicited protection in mice against experimental challenge. These results suggest that RspA and RspB participate in initiation of biofilm formation through their binding abilities to abiotic and biotic surfaces.     

Occurrence of Erysipelothrix rhusiopathiae on pork and in pig slurry, and the distribution of specific antibodies in abattoir workers

Strains of Erysipelothrix rhusiopathiae isolated at 19 pig farms serving a certain abattoir, and on pork and in workers of this abattoir were studied. Mouse-pathogenic E. rhusiopathiae was found in pig slurry from two farms (11%). The strains belonged to serotypes 7 and 16 (both from the same farm) or were untypable. In pig slurry from the abattoir lairage only serotype 2 strains were found and all were pathogenic to mice. Mouse-pathogenic E. rhusiopathiae strains of serotype 2 were also recovered from 25 pork lions (25%). A mouse-pathogenic E. rhusiopathiae (serotype 2) strain was isolated from one of the 16 hand infections of slaughterhouse workers. The E. rhusiopathiae strains were phenotypically grouped by the API 50 CH system. Variations were demonstrated for the different serotypes. In 20 of 138 workers antibodies against E. rhusiopathiae were found; 14 had increased levels of IgG antibodies, seven had increased levels of IgM antibodies and one had an increased level of both.     

Isolation of Erysipelothrix rhusiopathiae from apparently healthy pigs reared under intensive and free range systems of management

The carriage of Erysipelothrix rhusiopathiae by pigs reared under free range and intensive systems of management was compared. Large white (exotic) breeds kept under an intensive system and local (native) breeds kept under a free range system were studied. Of the 29 pigs kept under the intensive system, 44.8% carried E. rhusiopathiae in their tonsils while 51.7% of pigs kept under free range system also carried the organism in their tonsils. In each of the systems 6.9% of the pigs carried E. rhusiopathiae in their bile and muscles. Blood samples from all the animals surveyed were negative for the organism. There was no significant difference in the carriage of E. rhusiopathiae in pigs reared under the two systems of management. The ubiquity of E. rhusiopathiae in the environment, its resistance to environmental influences, poor standards of hygiene and the problem of detecting apparently healthy animals, are possible epidemiological factors which may have increased the carrier rate in the intensive system where E. rhusiopathiae was supposed to be less. The total number of carrier-pigs in the intensive system was 44.8% while in the free range system it was 51.7%.     

Persistence and Distribution of Erysipelothrix rhusiopathiae and Bacterial Indicator Organisms on Land Used for Disposal of Piggery Effluent

Erysipelothrix rhusiopathiae was isolated from 15 of 40 effluents collected from commercial piggeries. The organism was isolated from soil and pasture of experimental disposal sites for up to two weeks after application of effluent naturally infected with Ery. rhusiopathiae. The organism was more commonly isolated from soil than pasture. Times for 90% reduction (T₉₀ values) of indicator organisms over a six week period following the effluent applications where Ery. rhusiopathiae was detected for 7 d or more, were 8–19 d for faecal coliforms in top soil and 5–12 d on pasture. T₉₀ for faecal streptococci was 10–14 d in soil and 8–11 d on pasture. Laboratory investigations indicated that the death rate of Ery. rhusiopathiae was up to six times greater than Escherichia coli in soil at field capacity. In dry soil the differences in die-out rate of the two organisms was less marked.     

Erysipelothrix rhusiopathiae neuraminidase and its role in pathogenicity

The role of the enzyme neuraminidase in pathogenicity of the bacillus Erysipelothrix rhusiopathiae was studied. Different substances with low and high molecular weight were tested as inducers of E. rhusiopathiae neuraminidase biosynthesis. It was found that macromolecular complexes induce the secretion of the enzyme. K(M) values for different substrates showed that the affinity of the E. rhusiopathiae neuraminidase increases in parallel with the enlargement of the molecular weight of glycoproteins. Results from the rabbits skin test confirmed the role of E. rhusiopathiae neuraminidase as a factor of pathogenicity with spreading functions.     

The genome of Erysipelothrix rhusiopathiae, the causative agent of swine erysipelas, reveals new insights into the evolution of firmicutes and the organism's intracellular adaptations

Erysipelothrix rhusiopathiae is a Gram-positive bacterium that represents a new class, Erysipelotrichia, in the phylum Firmicutes. The organism is a facultative intracellular pathogen that causes swine erysipelas, as well as a variety of diseases in many animals. Here, we report the first complete genome sequence analysis of a member of the class Erysipelotrichia. The E. rhusiopathiae genome (1,787,941 bp) is one of the smallest genomes in the phylum Firmicutes. Phylogenetic analyses based on the 16S rRNA gene and 31 universal protein families suggest that E. rhusiopathiae is phylogenetically close to Mollicutes, which comprises Mycoplasma species. Genome analyses show that the overall features of the E. rhusiopathiae genome are similar to those of other Gram-positive bacteria; it possesses a complete set of peptidoglycan biosynthesis genes, two-component regulatory systems, and various cell wall-associated virulence factors, including a capsule and adhesins. However, it lacks many orthologous genes for the biosynthesis of wall teichoic acids (WTA) and lipoteichoic acids (LTA) and the dltABCD operon, which is responsible for d-alanine incorporation into WTA and LTA, suggesting that the organism has an atypical cell wall. In addition, like Mollicutes, its genome shows a complete loss of fatty acid biosynthesis pathways and lacks the genes for the biosynthesis of many amino acids, cofactors, and vitamins, indicating reductive genome evolution. The genome encodes nine antioxidant factors and nine phospholipases, which facilitate intracellular survival in phagocytes. Thus, the E. rhusiopathiae genome represents evolutionary traits of both Firmicutes and Mollicutes and provides new insights into its evolutionary adaptations for intracellular survival.     

Serological and pathogenic characterization of Erysipelothrix rhusiopathiae isolates from two human cases of endocarditis in Japan

We characterized the serological and pathogenic properties of two Erysipelothrix rhusiopathiae isolates from human cases of infective endocarditis in Japan. One isolate was recovered from a fisherman, and was identified as serovar 3, which is known to be prevalent among fish isolates. This strain exhibited high virulence in mice but was avirulent in swine. Another was untypable, and avirulent in both mice and swine. Our results suggest that various serological and athogenical types of E. rhusiopathiae can induce human endocarditis. This is the first report to characterize the pathogenicity of E. rhusiopathiae isolates from human endocarditis.     

Erysipelas Serum Titration with Sheep Red Blood Cells Passively Sensitized with a Cellular Extract

We have demonstrated that sheep red blood cells can be passively sensitized with an extract from Erysipelothrix rhusiopathiae. Diagnostic differential hemagglutination titrations may then be made with porcine serum for Erysipelas antibody.     

Characterization of Erysipelothrix rhusiopathiae isolated from an opossum (Didelphis virginiana) with septicemia

Erysipelothrix rhusiopathiae was isolated from a wild-caught opossum (Didelphis virginiana). The opossum was quarantined in isolation and removed from contact with other animals. After a 2-mo period it was found dead in its cage, and presented for postmortem examination. Pure cultures of Erysipelothrix rhusiopathiae (SLU isolate) were recovered from heart blood, liver, spleen and lungs. To compare pathogenicity, an experimental infection was attempted in CF1 mice with a single dose of 1.5 x 10(7) organisms of both an ATCC standard strain and SLU isolate of E. rhusiopathiae. Similar signs, lesions and results of culture were found for both strains. The findings suggest that opossums can be infected with E. rhusiopathiae.     

DNA relatedness among Erysipelothrix rhusiopathiae strains representing all twenty-three serovars and Erysipelothrix tonsillarum.

The levels of relatedness among strains of Erysipelothrix rhusiopathiae (serovars 1 through 23 and type N) were estimated by performing DNA-DNA hybridization experiments with the type strains of E. rhusiopathiae and Erysipelothrix tonsillarum, which are the two Erysipelothrix species that have been described. Two distinct DNA relatedness groups were identified. The group 1 strains, representing serovars 1, 2, 4 through 6, 8, 9, 11, 12, 15 through 17, 19, and 21 and type N, exhibited more than 73% hybridization with the type strain of E. rhusiopathiae but less than 24% hybridization with the type strain of E. tonsillarum. Group 2 included serovar 3, 7, 10, 14, 20, 22, and 23 strains, and these strains exhibited more than 66% hybridization with the type strain of E. tonsillarum but less than 27% hybridization with the type strain of E. rhusiopathiae. Strains representing serovars 13 and 18 exhibited low levels of hybridization (16 to 47%) with both of the type strains, indicating that these serovars may be members of a new genomic species. The members of the E. rhusiopathiae and E. tonsillarum groups resembled each other in many phenotypic characteristics, but differed in their ability to produce acid from saccharose and in their pathogenicity for swine. Our results confirm that the genus Erysipelothrix contains two main genomic species, E. rhusiopathiae and E. tonsillarum, which can be differentiated into serovars.     

Protective immunity of SpaA-antigen producing Lactococcus lactis against Erysipelothrix rhusiopathiae infection

AIMS: To develop an economical, safe and simple vaccination system against swine erysipelas using SpaA-antigen producing Lactococcus lactis. METHODS AND RESULTS: The spaA gene of Erysipelothrix rhusiopathiae was inserted into a shuttle plasmid pSECE1 to construct pSECE1.3. The SpaA produced in L. lactis maintained a stable antigenicity without degrading in growth. After mice were inoculated intranasally and orally with pSECE1.3-carrying L. lactis cells, IgG and IgA specific to SpaA were detected, and all the mice survived a challenge with 100 LD(50) of E. rhusiopathiae Tama-96 in the inner thigh. CONCLUSIONS: SpaA-producing L. lactis appears useful as an effective subunit vaccine against swine erysipelas. SIGNIFICANCE AND IMPACT OF THE STUDY: In this vaccination system, purification of the antigen and injection are unnecessary, leading to a reduced production cost, reduced labour and less stress to the animals. This vaccination system of the lactic acid bacteria should be a safe and suitable vehicle for a polyvalent vaccine.     

Isolation of Erysipelothrix rhusiopathiae from a red-tailed hawk (Buteo jamaicensis) with a concurrent pox virus infection

Erysipelothrix rhusiopathiae was isolated from the spleen, liver, lung, heart, kidney, and skin of a red-tailed hawk (Buteo jamaicensis) which had a concurrent avian pox virus infection. The hawk had been housed on a farm with domestic turkeys, providing a possible source of the E. rhusiopathiae.     

安徽部分地区猪丹毒杆菌的分离鉴定及生物学特性研究

【目的】对安徽省8个不同地区猪场临床疑似猪丹毒病/死猪进行细菌分离鉴定,并研究其生物学特性。【方法】通过形态学及培养特性观察、生化试验、PCR方法对菌株进行鉴定,并进行药物感受性实验及免疫保护实验。【结果】共分离到29株猪丹毒杆菌,源自8个地区的猪丹毒杆菌分离菌具有较一致的形态特征和相似的生化特性。对29株猪丹毒杆菌进行18种常用抗菌药物的药敏试验,结果显示分离菌对氨苄西林、头孢曲松敏感率均达100%,其次是青霉素93%、红霉素89.7%和头孢噻肟75.9%,对其他13种药物则表现不同程度的耐药性。8株不同地区猪丹毒杆菌分离菌的LD50在(14.30?2.36)×102 CFU/mL之间,显示分离菌对小鼠均具有较强的致病力。商品化猪丹毒G4T10株弱毒疫苗2次颈部皮下免疫小鼠后,分别用剂量为100 LD50的8株猪丹毒杆菌分离菌腹腔攻毒小鼠,免疫保护率为100%。【结论】安徽地区猪丹毒发生有上升趋势,不同地区的猪丹毒杆菌分离菌具有较为一致的生物学特性,青霉素类和头孢类抗菌药物有显著疗效,使用猪丹毒G4T10株弱毒疫苗可产生有效的免疫保护力。     

猪丹毒丝菌天然SpaA和重组SpaA-N免疫保护效果的评价

【目的】本试验以小鼠为动物模型,评估了猪丹毒丝菌重组表面保护性抗原A的N端保护区域(rSpaA-N)和天然SpaA的免疫保护效果。【方法】将猪丹毒丝菌C43311株SpaA-N以可溶形式表达在大肠杆菌BL21中,用GST Bind Resin纯化试剂盒纯化rSpaA-N,采用电洗脱法从猪丹毒丝菌C43311株NaOH提取抗原中纯化天然SpaA,将rSpaA-N、天然SpaA和NaOH提取抗原制成亚单位疫苗,同时设GST及生理盐水对照组,间隔2周分3次皮下免疫小鼠,第3次免疫后2周用100LD50猪丹毒丝菌C43065株进行腹腔攻毒,采用间接ELISA方法检测免疫组小鼠血清的抗体动态变化。【结果】SDS-PAGE结果显示,采用GST Bind Resin纯化试剂盒和电洗脱法纯化得到了66kDa的rSpaA-N和64kDa的天然SpaA,蛋白含量分别为1.34mg/mL和1.26mg/mL,而Western印迹结果表明rSpaA-N和纯化前后的SpaA具有良好的免疫反应性。保护试验结果表明,不同免疫剂量的rSpaA-N组、天然SpaA组和NaOH提取抗原组均能完全保护小鼠受强毒株C43065的致死性攻击,而GST组和生理盐水组小鼠攻毒后全部死亡。ELISA检测结果表明,在不同免疫剂量的rSpaA-N组、天然SpaA组和NaOH提取抗原组小鼠血清中的抗体效价之间无显著差异(P0.05)。【结论】本研究结果表明rSpaA-N具有良好的免疫保护作用,可以作为猪丹毒亚单位疫苗。     

Nucleotide sequence analysis and heterologous expression of the Erysipelothrix rhusiopathiae dnaJ gene

Abstract DNA sequence analysis of chromosomal DNA from the Gram-positive facultative intracellular pathogen, Erysipelothrix rhusiopathiae has identified a dnaJ heat shock gene homolog. A 1109-bp open reading frame encoding dnaJ is located immediately 3' to the E. rhusiopathiae dnaK gene. The deduced DnaJ amino acid sequence exhibits the modular structure of other members of the DnaJ protein class including a glycine-rich region and the repeating consensus sequence CXXCXGXGX. Heterologous expression of the dnaJ sequence in Escherichia coli resulted in accumulation of a unique 38.9-kDa protein with an isoelectric point of 8.0. Deletion analysis of the dnaJ gene was used to confirm that the overproduced protein was encoded by the dnaJ sequence.     

A taxonomic study on erysipelothrix by DNA-DNA hybridization experiments with numerous strains isolated from extensive origins

The purpose of this study was to clarify the taxonomic relationship between all the serovars and species of the genus Erysipelothrix by performing DNA-DNA hybridization experiments, the customary criterion for separation of bacterial genospecies. A total of 93 strains were isolated from a wide variety of sources, including pigs affected with acute or chronic erysipelas, other diseased animals, healthy animals, fish, retail meats, and environmental materials from throughout the world during the period 1958 to 1996. The present data on phenotypic characterization and DNA relatedness values demonstrate that 24 strains (96%) of E. tonsillarum are avirulent for swine, whereas 39 strains (66%) of genomic E. rhusiopathiae induced generalized or local urticarial lesion in swine after intradermal inoculation. This observation suggests that genomic E. tonsillarum has little etiological significance. Three minor groups contained several strains which exhibited minimal association with each type strain of E. rhusiopathiae and E. tonsillarum. In conclusion, it was confirmed that members of the E. rhusiopathiae and E. tonsillarum groups resemble each other in regard to many phenotypic characteristics, but differ in their ability to produce acid from saccharose and in their pathogenicity for swine. The genus Erysipelothrix certainly contains two main species: E. rhusiopathiae and E. tonsillarum.     

Phylogenic and phenotypic characterization of some Eubacterium-like isolates from human feces: description of Solobacterium moorei Gen. Nov., Sp. Nov

Three isolated strains from human feces were characterized by biochemical tests and 16S rDNA analysis. Phylogenetic analysis revealed that these isolated strains were members of the Clostridium subphylum of gram-positive bacteria. The phenotypic characters resembled those of the genus Eubacterium, but these strains were shown to be phylogenetically distant from the type species of the genus, Eubacterium limosum. The strains showed a specific phylogenetic association with Holdemania filiformis and Erysipelothrix rhusiopathiae. Based on a 16S rDNA sequence divergence of greater than 12% with H. filiformis and E. rhusiopathiae, a new genus, Solobacterium, is proposed for three strains, with one species, Solobacterium moorei. The type strain of Solobacterium moorei is JCM 10645T.     

Induction of Experimental Chronic Arthritis in Rabbits by Cell-free Fragments of Erysipelothrix

A cell-free crude extract of Erysipelothrix rhusiopathiae injected by high pressure jet into the knee-joint of rabbits stimulated an acute, mild inflammatory reaction. Additional injections at 3-day intervals induced a chronic condition characterized by hyperplasia of the synovial cells and hypertrophy of the villi, due to infiltration by lymphocytes and plasma cells which formed aggregates resembling Allison-Ghormley bodies. There was also extensive proliferation of stroma vasculature and fibrous tissue. A similar jet injection of the diluent produced an early, transient, acute, and mild inflammation. A mechanism is postulated for fixation of one or more of the chemically characterized antigens in or near the synovium as a means of inducing the localized inflammatory response that predisposes the joint to infection.