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1.
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   
2.
Phenotypic properties and species-specific PCR tests based on the nuc gene of Staphylococcus intermedius and S. aureus, and a conserved region of 16S rDNA were used to identify 45 S. intermedius and four S. aureus isolated from samples of dogs during routine diagnostics. Four S. pseudintermedius strains used for control purposes reacted positively with the S. intermedius nuc PCR showing the close relationship between both species. Investigating the 45 S. intermedius and four S. pseudintermedius strains for the prevalence of the exfoliative toxin SIET encoding gene yielded the presence of the gene for 21 of the S. intermedius and two of the S. pseudintermedius strains. Partial sequencing of the toxin gene of a single S. intermedius strain and comparing this sequence with that obtained from GenBank revealed an almost complete identity. The presence of the exfoliative toxin gene could mainly be found among S. intermedius isolated from skin and wound infections and from otitis externa possibly indicating a role of this toxin for the clinical symptoms.  相似文献   
3.
In the present study 20 staphylococci isolated from lymph node abscesses of 19 goats of two herds in Western Poland could be identified as Staphylococcus aureus subsp. anaerobius. All 20 strains grew under microaerobic conditions, were negative in the catalase test, showed the typical phenotypic properties of 5. aureus and could genotypically be identified by a positive sa442, 235 rDNA, nuc, coa and spa PCR reaction. The variable regions of the coa and spa gene of the 20 strains appeared with uniform amplicon sizes, respectively. All 20 strains were negative for 12 additionally investigated enterotoxin encoding genes, tst and ssl7 and positive for the gene cap8. Identical properties could be observed for S. aureus subsp. anaerobius DSM 20714. Amplification and sequencing of kat gene of a single Staphylococcus aureus subsp. anaerobius strain of the present study and S. aureus subsp. anaerobius DSM 20714 revealed a complete identity of the kat sequences of both strains and a katB sequence obtained from GenBank (AJ000471). The bacteria were additionally investigated for relatedness by macrorestriction analysis of chromosomal DNA with subsequent pulsed-field gel electrophoresis (PFGE), yielding, corresponding to the above mentioned PCR results, identical PFGE patterns for all 20 Staphylococcus aureus subsp. anaerobius strains isolated in Western Poland and the S. aureus subsp. anaerobius reference strain DSM 20714.This indicates the clonal identity of the strains isolated in Western Poland and the S. aureus subsp. anaerobius reference strain. The route of infection of the two herds in Western Poland with a bacterial clone originally isolated in Spain remains unclear.  相似文献   
4.
In the present study 320 milk samples collected from 160 apparently healthy camels of three different locations in Sudan were investigated for the presence of Staphylococcus aureus resulting in the isolation of this bacterial pathogen from 28 milk samples from 24 camels. Twenty-five S. aureus were identified phenotypically and by PCR mediated amplification of species-specific genes or gene segments. Investigation of the S. aureus for toxinogenic potential revealed that three S. aureus strains were positive for the enterotoxin encoding gene sec and the genes seg, sei, sem, sen and seo, representing the egc gene cluster. In addition all 25 S. aureus were positive for the superantigen-like encoding gene ssl7 (set1). Partial sequencing of gene sec of the three S. aureus strains yielded an almost complete sequence identity to the sequence of the sec variant sec2. However, all three sec2 genes of the present study showed a deletion of one base causing a frame shift and a corresponding earlier stop codon.According to the present results, the raw camel milk collected from three locations in Sudan seems to be, at least at this stage, of minor importance as vector causing staphylococcal food poisoning.  相似文献   
5.
A total of 57 bacteria representing eight species of genus Arcanobacterium (A.) were investigated for hemolytic properties on blood agar containing sheep and rabbit blood and for CAMP-like reactions. An enhanced hemolysis on blood agar containing rabbit blood compared to sheep blood could be observed for A. haemolyticum, less pronounced for A. hippocoleae and A. pluranimalium.A synergistic hemolytic reaction with staphylococcal β-hemolysin appeared to be constantly visible for A. hippocoleae, A. pluranimalium and A. pyogenes, with Streptococcus agalactiae for A. phocae and A. haemolyticum, with Rhodococcus equi for A. phocae, A. haemolyticum, A. pluranimalium and A. pyogenes and with A. haemolyticum for A. hippocoleae, A. pluranimalium and A. pyogenes, respectively. A reverse CAMP-reaction in the zone of staphylococcal β-hemolysin could be observed for A. phocae and A. haemolyticum. In addition, a novel CAMP-like reaction could be noted between Psychrobacter phenylpyruvicus, identified by 16S rDNA sequencing, and A. phocae and A. haemolyticum. These synergistic or antagonistic hemolytic properties could possibly be used as additional criteria for identification of bacteria of genus Arcanobacterium.  相似文献   
6.
This study aims to understand the influence of salinity and labile organic matter removal on the fate and behavior of metals in coastal technosols. Two technosol cores were collected near the Lebanese shore. The cores were sectioned into layers; each layer was characterized for pH, salinity, electric conductivity, labile and total organic matter, grain size, and total and oxalate-extractable metals. Consequently, two saline solutions were used in desorption experiments to understand the role of ionic strength and labile organic matter on metal release. The results showed that the technosol layers were highly heterogeneous; most layers were enriched with Fe, Zn, Pb, and Cu. The mineralogical investigations showed that the metals, notably Fe, were not present as crystalline minerals, rather big percentages of the metals were found in amorphous or poorly crystalline phases. Desorption experiment showed that Mg release was dependent on salinity and organic matter in both technosols, while Pb release was dependent on both factors only in one. Additionally, Zn and Cu were associated to organic matter, and their release was conditioned by the removal of labile organic matter; iron was primarily found as amorphous or poorly crystalline phases, and salinity had a major role in its release. The role of ionic strength and labile organic matter removal on the behavior of metals in technosols was demonstrated. Finally, understanding metal dynamics between the solid and liquid compartments in technosols, especially where salt deposition occurs, is important to reduce unwanted metal leaching to groundwater or seawater and transfer to biota.  相似文献   
7.
In the present study, the 16S-23S rDNA intergenic spacer region (ISR) of Arcanobacterium (A.) bialowiezense DSM 17162, A. bonasi DSM 17163, A. bernardiae DSM 9152, A. haemolyticum DSM 20595, A. hippocoleae DSM 15539, A. phocae DSM 10002, A. pluranimalium DSM 13483 and A. pyogenes DSM 20630 was amplified, sequenced and compared with the corresponding 16S rRNA gene sequences yielding comparable phylogenetic relationships. The ISR sequence of A. bialowiezense and A. bonasi allowed the design of species-specific oligonucleotide primers which could successfully be used for PCR-mediated identification of previously characterized A. bialowiezense and A. bonasi isolated from infections of the European bison. The presented molecular identification might help to improve a future diagnosis of both newly described bacterial pathogens.  相似文献   
8.
In the present study four methicillin-resistant Staphylococcus pseudintermedius (MRSP) strains isolated from a dog (n = 3) and the anterior nares of the dog owner (n = 1) were investigated by conventional and molecular methods. The species identity of the four S. pseudintermedius strains was confirmed by conventional methods, by PCR mediated amplification of S. intermedius/S. pseudintermedius specific segments of thermonuclease encoding gene nuc and by restriction fragment length polymorphism analysis of phosphoacetyltransferase encoding gene pta. Investigation of the four S. pseudintermedius for toxinogenic potential revealed that all four strains were positive for the exfoliative toxin encoding gene siet and the leukotoxin encoding genes lukS, lukF. The oxacillin and penicillin resistance of the four S. pseudintermedius strains could be determined by cultivation of the strains on oxacillin resistant screening agar base, ChromID MRSA Agar and Brilliance MRSA Agar and by multiplex PCR detecting the resistance genes mecA and blaZ. The genetic relatedness of the strains was studied by macrorestriction analysis of their chromosomal DNA using pulsed field gel electrophoresis (PFGE). According to PFGE all four S. pseudintermedius strains represent an identical bacterial clone indicating a cross transmission between the dog and the dog owner.  相似文献   
9.
In this study, a F2 population derived from the cross between deep-rooted variety “Moroberekan” with shallow-rooted variety “IR20” were used to identify and validate of SSR markers associated with root morphological traits. The F2 lines were divided into two groups. In the first group, 152 seedling having minimum of four tillers were chosen and separated into four plantlets to plant them in polyvinyl chloride pipes for root study under well-watered (WW) condition at maturity stage. The lines were genotyped using SSR markers. QTLs for maximum root length (MRL) and root dry weight showed co-segregation with RM472, RM7 and RM201. The same material was forwarded to next generation (F3) to validate the linked markers under both WW and low-moisture stress (LMS) conditions. These three markers were associated consistently with MRL across generations. In the second group, 1240 F2 plants were forwarded to F5 using SSD breeding method to test the effectiveness of the marker-assisted selection (MAS) method for drought resistant. The high performing genotypic group was significantly superior to low performing genotypic group for MRL, grain yield, root volume, root dry weight and root number, indicating the efficiency of MAS for root-related traits under LMS. Comparing MAS with farmer selection in F6, the results showed that MAS group means were significantly different from farmer group means for MRL, root volume, root dry weight and root number. Thus, MAS was combined with participatory selection to select five high-yielding and deep rooted promising lines. Identification of stable QTL for root morphological traits under WW and LMS conditions can aid in MAS and to introduce them into varieties with good yield potential and accepted by farmer.  相似文献   
10.
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   
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