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Bordetella pertussis vaccine strains and circulating isolates in Serbia
In Serbia, whole cell pertussis vaccine was introduced in 1957. Current composition of the vaccine has been used since 1985 and contains four autochthonous strains of Bordetella pertussis isolated from 1957 to 1984. To monitor changes in bacterial population, 70 isolates collected from 1953 to 2000 were studied together with the vaccine strains. The methods included serotyping of fimbriae (Fim), genotyping of pertactin (prn) and pertussis toxin S1 subunit (ptxA). and pulsed-field gel electrophoresis analysis. Shift from ptxA2 to ptxA1 has been observed in isolates since the late of 1960s. All isolates from 1980 to 1984 harbored ptxA1. Re-appearance of the ptxA2 allele followed an addition of the two strains harboring ptxA1 in the vaccine in 1985. The allele prn1 was predominant among the Serbian isolates, though prn3 and prn11 have been detected since 1981 and 1984. The allele prn2 was found only in two strains isolated in 2000. Serotype Fim2.3 disappeared before 1980 and serotype Fim2 became predominant since then. The Serbian vaccine strains showed differences in ptxA and pm. The results of this present study indicate that the B. pertussis population in Serbia is different from other vaccinated populations and that this difference may be related to the vaccine used. (C) 2009 Elsevier Ltd. All rights reserved
Cysteine proteinase inhibitor Act d 4 is a functional allergen contributing to the clinical symptoms of kiwifruit allergy
Kiwifruit has become a frequent cause of fruit allergy in the recent years. The molecular basis of type I hypersensitivity to kiwifruit is attributed to 11 IUIS allergens, with Act d 1, Act d 2 and Act d 5 characterized in extenso. Evaluation of the allergenic properties of Act d 4, a cysteine proteinase inhibitor from green kiwifruit (Actinidia deliciosa) was performed in this study. Identity of the purified glycoprotein was determined by Edman degradation and by mass fingerprint whereby more than 90% of the primary structure of the mature kiwifruit cystatin was confirmed. Using MALDI TOF analysis, molecular masses of 10902.5 and 11055.2 Da were detected for Act d 4, respectively. Positive skin prick reactivity with Act d 4 was induced in three kiwifruit allergic patients, as well as the upregulation of CD63 and CD203c molecules in the basophile activation assay. The IgE reactivity was detected in dot blot analysis while Western blot analysis was negative using sera from six kiwifruit patients, suggesting the presence of conformational IgE epitopes on the Act d 4 molecule. As activator of effector cells in type I hypersensitivity Act d 4 is a functional allergen contributing to the clinical symptoms of kiwifruit allergy
Ispitivanje stabilnosti vakcine kućne prašine za sublingvalnu imunoterapiju
Allergen-specific immunotherapy with house dust mite (HDM) allergen extracts can effectively alleviate the symptoms of allergic rhinitis and asthma. The efficacy of the immunotherapeutic treatment is highly dependent on the quality of house dust mite vaccines. This study was performed to assess the stability of house dust mite allergen vaccines prepared for sublingual immunotherapy. Lyophilized Dermatophagoides pteronyssinus (Dpt) mite bodies were the starting material for the production of sublingual vaccines in four therapeutic concentrations. The stability of the extract for vaccine production, which was stored below 4 °C for one month, showed consistence in the protein profile in SDS PAGE. ELISA-inhibition showed that the potencies of Dpt vaccines during a 12 month period were to 65-80 % preserved at all analyzed therapeutic concentrations. This study showed that glycerinated Dpt vaccines stored at 4°C preserved their IgE-binding potential during a 12 month period, implying their suitability for sublingual immunotherapeutic treatment of HDM allergy.Alergen-specifična imunoterapija predstavlja postupak koji može da promeni tok bolesti kod alergijskog rinitisa i astme. Kvalitet vakcine pripremljene od kućnih grinja značajno utiče na efikasnost imunoterapeutskog tretmana. Ispitivanje je imalo za cilj procenu stabilnosti vakcine kućnih grinja namenjene za sublingvalnu imunoterapiju. Telo liofilozovanih Dermatophagoides pteronyssinus grinja (Dpt-grinja) upotrebljeno je kao polazni materijal za proizvodnju sublingvalne vakcine u 4 različita terapeutska razblaženja. Potentnost Dpt vakcina praćena ELISA-inhibicijom u 4 terapeutska razblaženja, nakon 12 meseci zadržan je u svim razblaženjima u opsegu 65-80%. Ispitivanje je pokazalo da glicerolom stabilizovane Dpt vakcine za subligvalnu imunoterapiju, uz čuvanje na 4°C zadržavaju alergeni potencijal ( gt 65%) nakon 12 meseci od njihove pripreme, i kao takve mogu se koristiti za tretman alergije na kućne grinje
The presence of prtP proteinase gene in natural isolate Lactobacillus plantarum BGSJ3-18
Aims: The study of proteolytic activity and examination of proteinase gene region organization in proteolytically active Lactobacillus plantarum strains from different natural sources. Methods and Results: A set of 37 lactobacilli was distinguished by using multiplex PCR assay. Results showed that 34 strains were Lact. plantarum and three of them were Lact. paraplantarum. The examination of proteolytic activity revealed that 28 Lact. plantarum and two Lact. paraplantarum hydrolyse beta-casein. Further analyses of all proteolytically active Lact. plantarum with primers specific for different types of CEPs demonstrated that strain BGSJ3-18 has prtP catalytic domain as well as prtP-prtM intergenic region showing more than 95% sequence identity with the same regions present in Lact. paracasei, Lact. casei and L. lactis. No presence of prtB, prtH or prtR proteinase genes was detected in any of tested Lact. plantarum strains. Conclusions: One out of 28 analysed Lact. plantarum strains harbours the prtP-like gene. The other proteolytically active Lact. plantarum probably possesses a different type of extracellular proteinase(s). Significance and Impact of the Study: It is the first report about the presence of the prtP-like gene in Lact. plantarum, which illustrates the mobility of this gene and its presence in different species
A successful use of a new shuttle cloning vector pA13 for the cloning of the bacteriocins BacSJ and acidocin 8912
The aim of this paper was to research the molecular cloning of genes encoding the novel bacteriocin BacSJ from Lactobacillus paracasei subsp. paracasei BGSJ2-8 by using a newly constructed shuttle cloning vector pA13. A new shuttle-cloning vector, pA13, was constructed and successfully introduced into Escherichia coli, Lactobacillus and Lactococcus strains, showing a high segregational and structural stability in all three hosts. The natural plasmid pSJ2-8 from L. paracasei subsp. paracasei BGSJ2-8 was cloned in the pA13 using BamHI, obtaining the construct pB5. Sequencing and in silico analysis of the pB5 revealed 15 open reading frames (ORF). Plasmid pSJ2-8 harbors the genes encoding the production of two bacteriocins, BacSJ and acidocin 8912. The combined N-terminal amino acid sequencing of BacSJ in combination with DNA sequencing of the bacSJ2-8 gene enabled the determination of the primary structure of a bacteriocin BacSJ. The production and functional expression of BacSJ in homologous and heterologous hosts suggest that bacSJ2-8 and bacSJ2-8i together with the genes encoding the ABC transporter and accessory protein are the minimal requirement for the production of BacSJ. Biochemical and genetic analyses showed that BacSJ belongs to the class II bacteriocins. The shuttle cloning vector pA13 could be used as a tool for genetic manipulations in lactobacilli and lactococci
Regulation of the sdsA alkyl sulfatase of Pseudomonas sp ATCC19151 and its involvement in degradation of anionic surfactants
Aims: The presented study was aimed to reveal transcriptional regulation of genes involved in SDS degradation (sdsA and sdsB) in Pseudomonas sp. ATCC19151. In addition, the ability of Pseudomonas sp. ATCC19151 to degrade anionic surfactants present in commercial detergent and septic tank drain was analysed. Methods and Results: Strain ATCC19151, at 30 degrees C, degrades all SDS present in the liquid medium (up to 4% w/v of SDS) within 48 h. ATCC19151 grows in the presence up to 15% (v/v) 'Fairy' commercial detergent and mineralizes 35% of present anionic surfactants. Analysis of the sdsA (P(sdsA)) and divergent sdsB (P(sdsB)) gene promoter activities revealed that SdsB acts as a positive regulator of sdsA and sdsB transcription. P(sdsA) and P(sdsB) activities rose significantly in the presence of the SDS, indicating inducibility of sdsA and sdsB transcription. DNA-binding assay indicated that SdsB directly regulates the transcription of sdsA and sdsB genes. Strain ATCC19151 grew in a sterile septic tank drain and on commercial detergent as sole source of carbon. Conclusions: SdsA enables Pseudomonas sp. ATCC19151 to utilize SDS as a sole carbon source. SdsB is positive transcriptional regulator of sdsA and sdsB genes. Significance and Impact of the Study: Ability of ATCC19151 to degrade anionic surfactants makes Pseudomonas sp. ATCC19151 a good candidate for bioremediation
Evaluation of the thermal stability and digestibility of heterologously produced banana lectin
The thermal stability of recombinant mannose-specific banana lectin (rBanLec), as well as its stability under conditions of simulated gastro-intestinal fluid (SGF), was investigated. rBanLec was heterologously produced in Escherichia coli, Molecular mass of rBanLec, assessed by ESI-TOF mass spectrometry, was 15972.2 Da. Thermodynamic parameters for rBanLec denaturation, obtained by differential scanning calorimetry (DSC), revealed a transition maximum temperature (T-m) of 60.8 degrees C, calorimetric enthalpy (H-cal) of 136.17 kcal/mol and van't Hoff enthalpy (H-VH) of 50.27 kcal/mol. rBanLec was stable following an incubation for 2 h in SGF, and then for I h, in the simulated intestinal fluid (SIF). Intact primary structure, biological and immunological reactivity of rBanLec were all preserved following treatment under SGF and SIF conditions. In conclusion, rBanLec is a good candidate for the novel bioadhesive lectin-based drug delivery systems to the gastro-intestinal tract (GIT). (C) 2009 Elsevier Ltd. All rights reserved
In vitro stimulation of Balb/c and C57 BL/6 splenocytes by a recombinantly produced banana lectin isoform results in both a proliferation of T cells and an increased secretion of interferon-gamma
Lectins are widely used in many types of assay but some lectins such as banana lectin (BanLec) are recognised as potent immunostimulators Although BanLec's structure and binding characteristics are now familiar, its immunostimulatory potential has not yet been fully explored The synthesis by recombinant technology of a BanLec isoform (rBanLec) whose binding properties are similar to its natural counterpart has made it possible to overcome the twin problems of natural BanLec's microheterogeneity and low availability This study's aim is to explore the immunostimulatory potential of rBanLec in the murine model Analyses of the responses of Balb/c- and C57 BL/6-originated splenocytes to in vitro rBanLec stimulation were performed to examine the dependency of rBanLec's immunostimulatory potential upon the splenocytes' genetic background It is shown that the responses of Balb/c- and C57 BL/6-originated splenocytes to rBanLec stimulation differ both qualitatively and in intensity. The hallmarks of the induced responses are T lymphocyte proliferation and intensive interferon-gamma secretion Both phenomena are more marked in Balb/c-originated cultures; Balb/c-originated lymphocytes produce interleukin (IL)-4 and IL-10 following rBanLec stimulation Out results demonstrate that any responses to rBanLec stimulation are highly dependent upon genetic background. they suggest that genetic background must be an important consideration in any further investigations using animal models or when exploring rBanLec's potential human applications (C) 2009 Elsevier B V. All rights reserve
Construction of a new shuttle vector and its use for cloning and expression of two plasmid-encoded bacteriocins from Lactobacillus paracasei subsp paracasei BGSJ2-8
A new shuttle-cloning vector, pA13, was constructed and successfully introduced into Escherichia coli. Lactobacillus and Lactococcus strains. It showed high segregational and structural stability in all three hosts. The natural plasmid pSJ2-8 from L paracasei subsp. paracasei BGSJ2-8 was cloned into pA13 using BamHI to obtain the construct, pB5. Sequencing and in silico analysis of pB5 revealed fifteen open reading frames (ORF). Plasmid pSJ2-8 harbours genes encoding the production of two bacteriocins, BacSJ and acidocin 8912. Combined N-terminal amino acid sequencing of BacSJ in combination with DNA sequencing of the bacSJ2-8 gene enabled determination of the primary structure of bacteriocin BacSJ. The bacSJ2-8 gene encodes 68-amino-acid peptide with a double-glycine leader peptide consisting of 18 amino acids, followed by the orf2 (bacSJ2-8i) which encodes the immunity protein of BacSJ. The production and functional expression of BacSJ in homologous and heterologous hosts suggest that bacSJ2-8 and bacSJ2-8i together with the genes encoding the ABC transporter and accessory protein are the minimal requirements for production of BacSJ. Biochemical and genetic analyses showed that BacSJ belongs to class II bacteriocins
Surface properties of Lactobacillus and Leuconostoc isolates from homemade cheeses showing auto-aggregation ability
Ten lactobacilli and one leuconostoc showing auto-aggregation ability were isolated from artisanal cheeses. Furthermore, non-aggregation strains were isolated from the same cheese sample, if existed. The analysis of factor(s) possibly involved in auto-aggregation was performed. The pretreatment of cells with proteinase K resulted in the disappearance of auto-aggregation ability. Moreover, cells also lost aggregation ability after three-times, successive washing in distilled water. Testing the ability of strain Lactobacillus paracasei subsp. paracasei BGSJ2-8 and its aggregation-deficient derivative BGSJ2-81 to co-aggregate with Listeria innocua ATCC33090, Escherichia coli ATCC25922 or Salmonella typhimurium TR251 showed that strain BGSJ2-8 co-aggregated with these strains, but derivative BGSJ2-81 was not. However, the treatment of L. paracasei subsp. paracasei BGSJ2-8 with proteinase K prior to co-aggregation tests resulted in losing co-aggregation ability. Surface properties of selected strains were analyzed by MATS (microbial adhesion to solvents) method. It was noticed that the strains with auto-aggregation ability were highly hydrophobic in comparison with aggregation-deficient ones. Comparative analyses of the surface features of strain L. paracasei subsp. paracasei BGSJ2-8 and its derivative BGSJ2-81 revealed notable difference