Pasteurella multocida contains multiple immunogenic haemin- and haemoglobin-binding proteins   总被引：1，自引：0，他引：1  

Bosch M  Garrido ME  Pérez de Rozas AM  Badiola I  Barbé J  Llagostera M 《Veterinary microbiology》2004,99(2):103-112

Iron-dependent outer membrane proteins (IROMPs) play an important role in bacterial pathogenesis and present several attributes of potential vaccine candidates. TBLASTN analysis of the Pasteurella multocida Pm70 genome using the same molecules of other bacterial pathogens as a query identified eight putative haemin and haemoglobin receptors for this organism. Quantitative binding assays have demonstrated that the proteins PM0040, PM0236, PM0741, PM1081, PM1428, PM0592 and HgbA bind both haemin and haemoglobin, whereas PM0576 and PM1282 ORFs only bind either haemoglobin or haemin, respectively. Furthermore, Western blot analysis showed that P. multocida-infected mice generate specific antibodies against PM0040, PM0236, PM0741, PM1081, PM1428, PM0592 and HgbA proteins. Nevertheless, inoculation of mice with any single one of these receptors alone did not protect against P. multocida infection.  相似文献   

Biological characteristics and pathogenicity of avian Escherichia coli strains.     

Wanderley Dias da Silveira  Alessandra Ferreira  Marcelo Brocchi  Luciana Maria de Hollanda  Antonio Fernando Pestana de Castro  Aureo Tatsumi Yamada  Marcelo Lancellotti 《Veterinary microbiology》2002,85(1):47-53

Fifty avian (chicken) pathogenic Escherichia coli strains (APEC) isolated from individuals suffering from omphalitis, septicaemia and swollen head syndrome, and 30 strains isolated from healthy chickens were studied regarding their biological characteristics such as serogroups, haemolysin, colicin, cytotoxin, toxin and siderophore production, adhesion capacity to in vitro cultivated cells, and absorption of Congo red dye. Serotyping demonstrated that most of the omphalitis and normal strains were untypable, whereas most of the septicaemic strains were either untypable or rough. There was no prevalent serogroup among the pathogenic strains studied. The capacity for adhesion and invasion of in vitro cultured cells (HeLa, HEp-2, KPCC), as well as the agglutination of different types of red blood cells and the LD50 of each strain were also evaluated. No correlation was observed between the biological characteristics and pathogenicity, except that colicin was characteristically produced by swollen head syndrome E. coli strains. No correlation was found between adhesion or haemagglutination patterns and pathogenicity. Only six of the 50 strains revealed invasive capacity and the strain that best invaded the cell lines was the one with the lowest LD50.  相似文献   

Serobiotypes and virulence genes of Escherichia coli strains isolated from diarrheic and healthy rabbits in Brazil   总被引：5，自引：0，他引：5  

Penteado AS  Ugrinovich LA  Blanco J  Blanco M  Blanco JE  Mora A  Andrade JR  Corrêa SS  Pestana de Castro AF 《Veterinary microbiology》2002,89(1):41-51

A total of 178 Escherichia coli isolates from diarrheic and healthy rabbits in the S?o Paulo State (Brazil) were serobiotyped and investigated by PCR for the presence of virulence genes. Among the 90 (50.6%) isolates which possessed the eae gene, 74 were from diarrheic animals and all but one encoded intimin beta. Sixty five (72.2%) of the eae+ isolates had insertion of the locus of enterocyte effacement locus in the pheU locus, 11 (12.2%) in the selC and 14 (15.6%) did not insert in either of these loci. All isolates were negative for genes of the E. coli enterotoxins, Stx1, Stx2, CNF1, CNF2 and EHEC hemolysin. The O132:H2 serotype was dominant, being present in 63 isolates (70%) of the 90 eae+ isolates, and 57 of the 63 isolates of this serotype belonged to biotype 30. PCR detected the gene for AF/R2 fimbriae in 75 (83.3%) of the 90 eae+ isolates. Adherence to HeLa cells was best detected following 6h incubation and a positive fluorescence actin staining (FAS) test was given by 52 isolates. These data show that isolates of E. coli associated with diarrhea in rabbits in Brazil possess the genotype and phenotype typically associated with rabbit enteropathogenic E. coli (EPEC). We conclude that EPEC that possess the eae gene are a common cause of diarrhea in Brazilian rabbit farms and that the pathogenic eae+ AF/R2+ isolates of O132:H2:B30 serobiotype are especially predominant.  相似文献   

Characterization of the functional domain of major surface protein 1a involved in adhesion of the rickettsia Anaplasma marginale to host cells     

de la Fuente J  Garcia-Garcia JC  Blouin EF  Kocan KM 《Veterinary microbiology》2003,91(2-3):265-283

The major surface protein (MSP) 1a of the genus type species Anaplasma marginale (Rickettsiales: Anaplasmataceae) has been shown to mediate adhesion, infection and transmission of the organism, as well as to contribute to protective immunity in cattle. MSP1a contains a variable number of tandemly repeated peptides in the amino-terminal region, while the remainder of the protein is highly conserved among isolates. The number of repeats varies among geographic isolates of A. marginale but is constant within an isolate and has been used as a stable genetic marker of isolate identity. Because the sequence of the tandem repeats is the most variable part of the protein among isolates, this region of the protein is most likely to be involved in adhesion to host cells, a prerequisite to infection. The purpose of this study was to characterize the organization and function of the MSP1a tandem repeats of A. marginale in adhesion to host cells. We demonstrated by use of recombinant mutant proteins that the tandemly repeated region of MSP1a was necessary and sufficient to mediate adhesion of MSP1a to tick cells and bovine erythrocytes. Synthetic peptides representing the predominant sequences of individual repeats were tested for their adhesive capacity for tick cell extract (TCE). Peptides containing acidic amino acids D or E at position 20 bound to TCE, while peptides with a G as the 20th amino acid were not adhesive to TCE. Antibodies produced in rabbits against a synthetic repeat peptide neutralized A. marginale infection of cultured tick cells, and the neutralization observed was similar to that effected by antibodies produced against the whole MSP1a recombinant protein. Analysis of tandemly repeated MSP1a peptides of several geographic isolates of A. marginale revealed a complex relationship between the msp1alpha genotype and the tick-transmissible phenotype of the isolate and suggested that both the sequence and conformation of the repeated peptides influenced the adhesive properties of MSP1a. These studies demonstrated that the tandemly repeated region of the protein mediates the adhesive function of MSP1a.  相似文献   

Mapping of QTLs in tomato line FLA456 associated with resistance to a virus causing tomato yellow leaf curl disease     

P. Kadirvel  R. de la Peña  R. Schafleitner  S. Huang  S. Geethanjali  L. Kenyon  W. Tsai  P. Hanson 《Euphytica》2013,190(2):297-308

Tomato (yellow) leaf curl disease (TYLCD) is a serious threat to tomato production in the tropics and subtropics. The genetics of resistance to Tomato yellow leaf curl Thailand virus Taiwan strain (TYLCTHV-[TW]) in a highly resistant tomato line FLA456 was studied through quantitative trait loci (QTL) analysis. Four QTLs named qTy4.1, qTy6.1, qTy10.1 and qTy11.1 were detected on chromosomes 4, 6, 10, and 11, respectively, through evaluation of an F₆ recombinant inbred line (RIL) population derived from a cross between FLA456 (resistant) and CLN1621L (susceptible). Gene action of all QTLs was recessive based on disease reaction of the F₁. The markers SINAC1 and SLM4-34 flanked qTy4.1 on chromosome 4, and SLM11-12 and SLM11-17 defined qTy11.1, which co-located with the previously identified Ty-5 and Ty-2 loci, respectively. qTy6.1 was flanked by the markers SLM6-55 and TES-0014, and qTy10.1 by the markers SLM10-80-SLM10-46 on chromosomes 6 and 10. The LOD values of the putative QTLs ranged from 2.79 to 13.76. The phenotypic variance explained by each QTL ranged from 7.1 to 31.9 %. The four QTLs collectively contributed about 60.5 % of the phenotypic variation in resistance against TYLCTHV-[TW]. Group mean severity scores of those RILs possessing three or four qTy were generally lower than RIL groups with only one or no qTy. Given the diversity of begomoviruses that cause TYLCD across the regions, the new QTLs from FLA456 would be valuable in tomato breeding for developing varieties with durable resistance. Two QTL intervals (qTy4.1 and qTy10.1) contained virus resistance candidate genes such as CTV.22 and eukaryotic translation initiation factor 4E.  相似文献   

A historical analysis of diversity trends in French and Dutch lettuce cultivars     

Mark van de Wouw  Rob van Treuren  Theo van Hintum 《Euphytica》2013,190(2):229-239

Using historical seed catalogues in combination with molecular fingerprinting data, diversity trends of lettuce, representing an important vegetable with active breeding programmes, were studied. Seed catalogues originating from France and the Netherlands from five different decades, the earliest dating from the 1840s, were checked for the occurence of lettuce cultivars. A total of 225 catalogues, with 7,311 records of lettuce, representing 878 different cultivars were found. The number of unique cultivars on offer by French and Dutch companies showed a small continuous increase until the 1960s, after which the number of cultivars on offer more than doubled to a total of 534 in the 1990s. Only a relatively small overlap between France and the Netherlands in the range of cultivars offered was observed. The 1960s appeared to be a period with many changes: the lowest genetic diversity in lettuce cultivars was found for this decade, whereas after the 1960s the number of companies supplying lettuce seeds reduced dramatically. The percentage of companies in a decade offering an identical cultivar decreased over time, and in the 1990s almost all cultivars were unique to only a single company. The possible relations of the observed trends with the developments in plant variety protection and in the plant breeding industry are discussed.  相似文献   

Rubber tree early selection for yield stability in time and among locations     

Lígia Regina Lima Gouvêa  Guilherme Augusto Peres Silva  Cecília Khusala Verardi  André Luis Bombonato de Oliveira  Elaine Cristine Piffer Gonçalves  Erivaldo José Scaloppi-Junior  Mário Luiz Teixeira de Moraes  Paulo de Souza Gonçalves 《Euphytica》2013,191(3):365-373

Rubber production in the rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg.] can be expressed differently in different environments. Thus the objective of the present study was to select productive progenies, stable and responsive in time and among locations. Thirty progenies were assessed by early yield tests at three ages and in three locations. A randomized block design was used with three replications and ten plants per plot, in 3 × 3 m spacing. The procedure of the mixed linear Reml/Blup model—restricted maximum likelihood/best non-biased linear prediction was used in the genetic statistical analyses. In all the individual analyses, the values observed for the progeny average heritability ( $ \hat{h}_{pa}^{2} $ ) were greater than those of the additive effect based on single individuals ( $ \hat{h}_{a}^{2} $ ) and within plot additive ( $ \hat{h}_{ad}^{2} $ ). In the joint analyses in time, there was genotype × test interaction in the three locations. When 20 % of the best progenies were selected the predicted genetic gains were: Colina G_G = 24.63 %, Selvíria G_G = 13.63 %, and Votuporanga G_G = 25.39 %. Two progenies were among the best in the analyses in the time and between locations. In the joint analysis among locations there was only genotype × location interaction in the first early test. In this test, selecting 20 %, the general predicted genetic gain was G_G = 25.10 %. Identifying progenies with high and stable yield over time and among locations contributes to the efficiency of the genetic breeding program. The relative performance of the progenies varies depending of the age of early selection test.  相似文献   

VvGAI1 polymorphisms associate with variation for berry traits in grapevine     

Alba M. Vargas  Loïc Le Cunff  Patrice This  Javier Ibáñez  M. Teresa de Andrés 《Euphytica》2013,191(1):85-98

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Assessing foraging strategies of herbivores in Mediterranean oak woodlands: a review of key issues and selected methodologies     

Maria Isabel Ferraz de Oliveira  Elsa Lamy  Miguel N. Bugalho  Margarida Vaz  Cristina Pinheiro  Manuel Cancela d’Abreu  Fernando Capela e Silva  Elvira Sales-Baptista 《Agroforestry Systems》2013,87(6):1421-1437

Montados are agro-silvo-pastoral ecosystems, typical of the Southwest Iberian Peninsula, of high socio-economic and conservation importance, where grazing is a dominant activity. Montados are characterized by an open tree canopy of Quercus sp. and a diverse undercover of shrubs and grasslands that constitute the plant food resources for grazing animals. Plant food resources of Montados are highly variable, both spatially and seasonally, in quantity and quality. Reliable and easy to use methods to monitor grazing are necessary to allow proper understanding of foraging strategies of grazing animals and to set sustainable grazing management. We describe the main characteristics of the plant food resources available for grazing animals, striking its variability, and revise the potential of using N-alkanes and saliva proteome methods to assess foraging strategies in Montados. In a scenario of dynamic multiple choices, we discuss the use of n-alkane methodology for the simultaneous estimation of diet composition and voluntary intake and saliva proteome as a mean of increasing the knowledge on diet adjustments.  相似文献   

RADIOGRAPHIC FEATURES OF PRIMARY AND CONCOMITANT FLEXOR ENTHESOPATHY IN THE CANINE ELBOW     

Evelien de Bakker  Jimmy H. Saunders  Henri van Bree  Ingrid Gielen  Bernadette Van Ryssen 《Veterinary radiology & ultrasound》2013,54(2):107-113

Primary flexor enthesopathy is a recently recognized elbow disorder and should be considered in the differential diagnosis of elbow lameness. For treatment planning purposes, it is important to make a distinction between primary and concomitant forms of the disease. The purpose of this prospective study was to compare radiographic findings for dogs with primary flexor enthesopathy (n = 17), concomitant flexor enthesopathy (n = 24), elbow dysplasia (n = 13), and normal dogs (n = 7). All dogs underwent a complete radiographic examination and each radiographic image was evaluated for the presence or absence of following characteristics: irregular medial humeral epicondyle, spur and calcified body. Additionally, the presence or absence of other elbow disorders (medial coronoid process disease, osteochondritis dissecans, ununited anconeal process, incongruity, subtrochlear sclerosis, and osteoarthritis) was recorded. Radiographic characteristics of flexor enthesopathy were found in 86% of painful joints in the primary flexor enthesopathy group and in 100% of painful joints in the concomitant flexor enthesopathy group. Radiographic characteristics of flexor enthesopathy were not found in sound elbow and elbow dysplasia groups. Frequencies and details of individual radiographic characteristics did not differ between primary and concomitant flexor enthesopathy groups. Findings support the use of radiography as a first screening method for detection of flexor enthesopathy, but not as a technique for distinguishing primary vs. concomitant forms.  相似文献