Protective Activity of Streptococcus pneumoniae Spr1875 Protein Fragments Identified Using a Phage Displayed Genomic Library

There is considerable interest in pneumococcal protein antigens capable of inducing serotype-independent immunoprotection and of improving, thereby, existing vaccines. We report here on the immunogenic properties of a novel surface antigen encoded by ORF spr1875 in the R6 strain genome. An antigenic fragment encoded by spr1875, designated R4, was identified using a Streptococcus pneumoniae phage displayed genomic library after selection with a human convalescent serum. Immunofluorescence analysis with anti-R4 antisera showed that Spr1875 was expressed on the surface of strains belonging to different serotypes. Moreover, the gene was present with little sequence variability in 27 different pneumococcal strains isolated worldwide. A mutant lacking Spr1875 was considerably less virulent than the wild type D39 strain in an intravenous mouse model of infection. Moreover, immunization with the R4 recombinant fragment, but not with the whole Spr1875 protein, induced significant protection against sepsis in mice. Lack of protection after immunization with the whole protein was related to the presence of immunodominant, non-protective epitopes located outside of the R4 fragment. In conclusion, our data indicate that Spr1875 has a role in pneumococcal virulence and is immunogenic. As the R4 fragment conferred immunoprotection from experimental sepsis, selected antigenic fragments of Spr1875 may be useful for the development of a pneumococcal protein-based vaccine

Transcriptome-wide expression profiling of Sporothrix schenckii yeast and mycelial forms and the establishment of the Sporothrix Genome DataBase

Contains fulltext : 226164.pdf (publisher's version ) (Open Access

Immunobiological characterization of genetic products, identified from whole genome lambda-display libraries of Pneumococcus

Objectives: Streptococcus pneumoniae is an important cause of morbidity and mortality worldwide, including meningitis. Here, we employed the isogenic Δspr0075-, Δspr1370- and Δspr1875-knock-out mutants of the DP1004 pneumococcal strain to investigate the role of these proteins in the interaction with microglia, the resident brain macrophages. Methods: By screening a whole genome phage display library with sera from patients, we identified clones carrying pneumococcal B-cell epitopes. Among these, we isolated six antigenic fragments of sequences matching three previously unidentified proteins, encoded by the ORFs spr0075, spr1370 and spr1875 of R6 strain genomic sequence. By using an in vitro infection model and a gentamicin protection assay we evaluated, respectively, the ability of microglial BV2 cells to phagocytose and kill the isogenic mutants and the survival of these bacteria inside the microglia. Results: All strains were efficiently internalized by BV2 cells; yet the levels of phagocytosis obtained with Δspr0075 strain were lower than those observed with the other groups. The survival of the deleted strains inside the microglia was significantly different. The residual CFU of Δspr1370 and Δspr1875 mutants were, indeed, respectively, higher and lower, than those observed with parental DP1004. Moreover, preliminary results indicate that a similar trend is also observed in a bactericidal assay using BV2 as effector cells. Conclusion: These findings indicate that the proteins encoded by spr1370 and spr1875 loci are involved in interaction between S. pneumoniae and microglia

Whole RNA-Sequencing and Transcriptome Assembly of Candida albicans and Candida africana under Chlamydospore-Inducing Conditions.

Candida albicans is the most common cause of life-threatening fungal infections in humans, especially in immunocompromised individuals. Crucial to its success as an opportunistic pathogen is the considerable dynamism of its genome, which readily undergoes genetic changes generating new phenotypes and shaping the evolution of new strains. Candida africana is an intriguing C. albicans biovariant strain that exhibits remarkable genetic and phenotypic differences when compared with standard C. albicans isolates. Candida africana is well-known for its low degree of virulence compared with C. albicans and for its inability to produce chlamydospores that C. albicans, characteristically, produces under certain environmental conditions. Chlamydospores are large, spherical structures, whose biological function is still unknown. For this reason, we have sequenced, assembled, and annotated the whole transcriptomes obtained from an efficient C. albicans chlamydospore-producing clinical strain (GE1), compared with the natural chlamydospore-negative C. africana clinical strain (CBS 11016). The transcriptomes of both C. albicans (GE1) and C. africana (CBS 11016) clinical strains, grown under chlamydospore-inducing conditions, were sequenced and assembled into 7,442 (GE1 strain) and 8,370 (CBS 11016 strain) high quality transcripts, respectively. The release of the first assembly of the C. africana transcriptome will allow future comparative studies to better understand the biology and evolution of this important human fungal pathogen

Whole RNA-Sequencing and Transcriptome Assembly of Candida albicans and Candida africana under Chlamydospore-Inducing Conditions.

Candida albicans is the most common cause of life-threatening fungal infections in humans, especially in immunocompromised individuals. Crucial to its success as an opportunistic pathogen is the considerable dynamism of its genome, which readily undergoes genetic changes generating new phenotypes and shaping the evolution of new strains. Candida africana is an intriguing C. albicans biovariant strain that exhibits remarkable genetic and phenotypic differences when compared with standard C. albicans isolates. Candida africana is well-known for its low degree of virulence compared with C. albicans and for its inability to produce chlamydospores that C. albicans, characteristically, produces under certain environmental conditions. Chlamydospores are large, spherical structures, whose biological function is still unknown. For this reason, we have sequenced, assembled, and annotated the whole transcriptomes obtained from an efficient C. albicans chlamydospore-producing clinical strain (GE1), compared with the natural chlamydospore-negative C. africana clinical strain (CBS 11016). The transcriptomes of both C. albicans (GE1) and C. africana (CBS 11016) clinical strains, grown under chlamydospore-inducing conditions, were sequenced and assembled into 7,442 (GE1 strain) and 8,370 (CBS 11016 strain) high quality transcripts, respectively. The release of the first assembly of the C. africana transcriptome will allow future comparative studies to better understand the biology and evolution of this important human fungal pathogen

Whole RNA-Sequencing and Transcriptome Assembly of Candida albicans and Candida africana under Chlamydospore-Inducing Conditions.

Candida albicans is the most common cause of life-threatening fungal infections in humans, especially in immunocompromised individuals. Crucial to its success as an opportunistic pathogen is the considerable dynamism of its genome, which readily undergoes genetic changes generating new phenotypes and shaping the evolution of new strains. Candida africana is an intriguing C. albicans biovariant strain that exhibits remarkable genetic and phenotypic differences when compared with standard C. albicans isolates. Candida africana is well-known for its low degree of virulence compared with C. albicans and for its inability to produce chlamydospores that C. albicans, characteristically, produces under certain environmental conditions. Chlamydospores are large, spherical structures, whose biological function is still unknown. For this reason, we have sequenced, assembled, and annotated the whole transcriptomes obtained from an efficient C. albicans chlamydospore-producing clinical strain (GE1), compared with the natural chlamydospore-negative C. africana clinical strain (CBS 11016). The transcriptomes of both C. albicans (GE1) and C. africana (CBS 11016) clinical strains, grown under chlamydospore-inducing conditions, were sequenced and assembled into 7,442 (GE1 strain) and 8,370 (CBS 11016 strain) high quality transcripts, respectively. The release of the first assembly of the C. africana transcriptome will allow future comparative studies to better understand the biology and evolution of this important human fungal pathogen

Draft genome sequence of the dimorphic fungus Sporothrix pallida, a nonpathogenic species belonging to Sporothrix, a genus containing agents of human and feline sporotrichosis

Submitted by Janaína Nascimento ([email protected]) on 2019-02-07T13:28:52Z No. of bitstreams: 1 ve_D’Alessandro_Enrico_etal_INI_2016.pdf: 154884 bytes, checksum: 5d4b0cd188bd4c8aa3edee70ed4da32a (MD5)Approved for entry into archive by Janaína Nascimento ([email protected]) on 2019-02-08T10:40:00Z (GMT) No. of bitstreams: 1 ve_D’Alessandro_Enrico_etal_INI_2016.pdf: 154884 bytes, checksum: 5d4b0cd188bd4c8aa3edee70ed4da32a (MD5)Made available in DSpace on 2019-02-08T10:40:00Z (GMT). No. of bitstreams: 1 ve_D’Alessandro_Enrico_etal_INI_2016.pdf: 154884 bytes, checksum: 5d4b0cd188bd4c8aa3edee70ed4da32a (MD5) Previous issue date: 2016University of Messina. Department of Veterinary Sciences. Division of Animal Production. Messina, Italy.University of Messina. Department of Chemical, Biological, Pharmaceutical and Environmental Sciences. Messina, Italy.Sun Yat-sen University. Third Affiliated Hospital. Department of Dermatology and Venereology. Guangzhou, Guangdong, China.Sun Yat-sen University. Third Affiliated Hospital. Department of Dermatology and Venereology. Guangzhou, Guangdong, China.Sun Yat-sen University. Third Affiliated Hospital. Department of Dermatology and Venereology. Guangzhou, Guangdong, China.CBS-KNAW Fungal Biodiversity Centre. Utrecht, The Netherlands.Fundação Oswaldo Cruz. Instituto Nacional de Infectologia Evandro Chagas. Laboratório de Micologia. Rio de Janeiro, RJ, Brasil.IRCCS Centro Neurolesi Bonino-Pulejo. Messina, Italy.University of Messina. Department of Chemical, Biological, Pharmaceutical and Environmental Sciences. Messina, Italy.University of Messina. Department of Chemical, Biological, Pharmaceutical and Environmental Sciences. Messina, Italy.CBS-KNAW Fungal Biodiversity Centre. Utrecht, The Netherlands.Sun Yat-sen University. Third Affiliated Hospital. Department of Dermatology and Venereology. Guangzhou, Guangdong, China.CBS-KNAW Fungal Biodiversity Centre. Utrecht, The Netherlands.University of Messina. Department of Chemical, Biological, Pharmaceutical and Environmental Sciences. Messina, Italy / IRCCS Centro Neurolesi Bonino-Pulejo. Messina, Italy.Sporothrix pallidais considered to be a mostly avirulent environmental fungus, phylogenetically closely related to the well-known pathogenSporothrix schenckii Here, we present the first assembly of its genome, which provides a valuable resource for future comparative genomic studies between nonpathogenic and pathogenicSporothrixspp

Binding of phage clones to mAb K20.

<p>Plates were sensitized with a mAb directed against phage protein III (1 µg/ml) and 100 µl of purified phage clones (10¹¹ pfu/ml) were added. After 1 h incubation, mAb K20 or an isotype-matched IgM (1 µg/ml) were added. Binding was detected by using alkaline phosphatase-conjugated anti-mouse IgM Ab. Pools of libraries, (pVIII-12aa/pVIII.Cys-Cys or pVIII-9aa.Cys/pVIII.Cys-Cys or pVIII-9aa/pVIII-9aa.Cys) were used in different phage selections. Results are reported in separate panels (A, B or C). Phage pC89, displaying wild-Type pVIII, was used as negative control. Data represents the means ± the SD of three determinations.</p