scholarly journals Unexpected Diversity of Wolbachia Associated with Bactrocera dorsalis (Diptera: Tephritidae) in Africa

Insects ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 155 ◽  
Author(s):  
Joseph Gichuhi ◽  
Fathiya M. Khamis ◽  
Johnnie Van den Berg ◽  
Sunday Ekesi ◽  
Jeremy K. Herren
Keyword(s):  
Surface Protein ◽  
Bactrocera Dorsalis ◽  
Wolbachia Surface Protein ◽  
Mitochondrial Haplotypes ◽  
Important Pest ◽  
Group B

Bactrocera dorsalis (Hendel) is an important pest of fruit-bearing plants in many countries worldwide. In Africa, this pest has spread rapidly and has become widely established since the first invasion report in 2003. Wolbachia is a vertically transmitted endosymbiont that can significantly influence aspects of the biology and, in particular, the reproduction of its host. In this study, we screened B. dorsalis specimens collected from several locations in Africa between 2005 and 2017 for Wolbachia using a PCR-based assay to target the Wolbachia surface protein wsp. Of the 357 individuals tested, 10 were positive for Wolbachia using the wsp assay. We identified four strains of Wolbachia infecting two B. dorsalis mitochondrial haplotypes. We found no strict association between the infecting strain and host haplotype, with one strain being present in two different host haplotypes. All the detected strains belonged to Super Group B Wolbachia and did not match any strains reported previously in B. dorsalis in Asia. These findings indicate that diverse Wolbachia infections are present in invasive populations of B. dorsalis.

scholarly journals Active and Passive Intranasal Immunizations with Streptococcal Surface Protein C5a Peptidase Prevent Infection of Murine Nasal Mucosa-Associated Lymphoid Tissue, a Functional Homologue of Human Tonsils

2005 ◽  
Vol 73 (12) ◽  
pp. 7878-7886 ◽  
Author(s):  
Hae-Sun Park ◽  
P. Patrick Cleary
Keyword(s):  
Nasal Mucosa ◽  
Lymphoid Tissue ◽  
Streptococcal Infection ◽  
Surface Protein ◽  
Effective Vaccine ◽  
Infection Model ◽  
Loss Of Function ◽  
Intranasal Immunization ◽  
Endemic Disease ◽  
Group B

ABSTRACT C5a peptidase, also called SCPA (surface-bound C5a peptidase), is a surface-bound protein on group A streptococci (GAS), etiologic agents for a variety of human diseases including pharyngitis, impetigo, toxic shock, and necrotizing fasciitis, as well as the postinfection sequelae rheumatic fever and rheumatic heart disease. This protein is highly conserved among different serotypes and is also expressed in human isolates of group B, C, and G streptococci. Human tonsils are the primary reservoirs for GAS, maintaining endemic disease across the globe. We recently reported that GAS preferentially target nasal mucosa-associated lymphoid tissue (NALT) in mice, a tissue functionally analogous to human tonsils. Experiments using a C5a peptidase loss-of-function mutant and an intranasal infection model showed that this protease is required for efficient colonization of NALT. An effective vaccine should prevent infection of this secondary lymphoid tissue; therefore, the potential of anti-SCPA antibodies to protect against streptococcal infection of NALT was investigated. Experiments showed that GAS colonization of NALT was significantly reduced following intranasal immunization of mice with recombinant SCPA protein administered alone or with cholera toxin, whereas a high degree of GAS colonization of NALT was observed in control mice immunized with phosphate-buffered saline only. Moreover, administration of anti-SCPA serum by the intranasal route protected mice against streptococcal infection. These results suggest that intranasal immunization with SCPA would prevent colonization and infection of human tonsils, thereby eliminating potential reservoirs that maintain endemic disease.

scholarly journals Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of glyceraldehyde-3-phosphate dehydrogenase fromStreptococcus agalactiaeNEM316

2014 ◽  
Vol 70 (7) ◽  
pp. 938-941 ◽  
Author(s):  
Revathi Nagarajan ◽  
Karthe Ponnuraj
Keyword(s):  
Signal Sequence ◽  
Structure Refinement ◽  
Group B Streptococcus ◽  
Surface Protein ◽  
Diffusion Method ◽  
Space Groups ◽  
Essential Enzyme ◽  
Bacteria And Fungi ◽  
Group B ◽  
Surface Adhesins

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an essential enzyme involved in glycolysis. Despite lacking the secretory signal sequence, this cytosolic enzyme has been found localized at the surface of several bacteria and fungi. As a surface protein, GAPDH exhibits various adhesive functions, thereby facilitating colonization and invasion of host tissues.Streptococcus agalactiae, also known as group B streptococcus (GBS), binds onto the host using its surface adhesins and causes sepsis and pneumonia in neonates. GAPDH is one of the surface adhesins of GBS binding to human plasminogen and is a virulent factor associated with host colonization. Although the surface-associated GAPDH has been shown to bind to a variety of host extracellular matrix (ECM) molecules in various bacteria, the molecular mechanism underlying their interaction is not fully understood. To investigate this, structural studies on GAPDH ofS. agalactiaewere initiated. ThegapCgene ofS. agalactiaeNEM316 encoding GAPDH protein was cloned into pET-28a vector, overexpressed inEscherichia coliBL21(DE3) cells and purified to homogeneity. The purified protein was crystallized using the hanging-drop vapour-diffusion method. The GAPDH crystals obtained in two different crystallization conditions diffracted to 2.8 and 2.6 Å resolution, belonging to two different space groupsP21andP212121, respectively. The structure was solved by molecular replacement and structure refinement is now in progress.

scholarly journals Reduced trans-placental transfer of group B Streptococcus surface protein antibodies in HIV-infected mother-newborn dyads

2016 ◽  
pp. jiw566
Author(s):  
Sonwabile Dzanibe ◽  
Peter V. Adrian ◽  
Sheila Z. Kimaro Mlacha ◽  
Ziyaad Dangor ◽  
Gaurav Kwatra ◽  
...  
Keyword(s):  
Placental Transfer ◽  
Group B Streptococcus ◽  
Surface Protein ◽  
Infected Mother ◽  
Group B

scholarly journals Acquisition of factor H by a novel surface protein on group B Streptococcus promotes complement degradation

2009 ◽  
Vol 23 (11) ◽  
pp. 3967-3977 ◽  
Author(s):  
Ravi Maruvada ◽  
Nemani V. Prasadarao ◽  
C. E. Rubens
Keyword(s):  
Group B Streptococcus ◽  
Surface Protein ◽  
Factor H ◽  
Group B

Association between maternal Group B Streptococcus surface-protein antibody concentrations and invasive disease in their infants

2015 ◽  
Vol 14 (12) ◽  
pp. 1651-1660 ◽  
Author(s):  
Ziyaad Dangor ◽  
Gaurav Kwatra ◽  
Alane Izu ◽  
Peter Adrian ◽  
Clare L Cutland ◽  
...  
Keyword(s):  
Group B Streptococcus ◽  
Surface Protein ◽  
Invasive Disease ◽  
Group B

scholarly journals Protein rib: a novel group B streptococcal cell surface protein that confers protective immunity and is expressed by most strains causing invasive infections.

1993 ◽  
Vol 177 (6) ◽  
pp. 1593-1603 ◽  
Author(s):  
M Stålhammar-Carlemalm ◽  
L Stenberg ◽  
G Lindahl
Keyword(s):  
Cell Surface ◽  
Protective Immunity ◽  
Group B Streptococcus ◽  
Rabbit Antiserum ◽  
Surface Protein ◽  
Amino Acid Sequences ◽  
Cell Surface Protein ◽  
Type Iii ◽  
Invasive Infections ◽  
Group B

The group B Streptococcus, an important cause of invasive infections in the neonate, is classified into four major serotypes (Ia, Ib, II, and III) based on the structure of the polysaccharide capsule. Since the capsule is a known virulence factor, it has been extensively studied, in particular in type III strains, which cause the majority of invasive infections. Two cell surface proteins, alpha and beta, have also been studied in detail since they confer protective immunity, but these proteins are usually not expressed by type III strains. We describe here a cell surface protein, designated protein Rib (resistance to proteases, immunity, group B), that confers protective immunity and is expressed by most strains of type III. Protein Rib was first identified as a distinct 95-kD protein in extracts of a type III strain, and was purified to homogeneity from that strain. Rabbit antiserum to protein Rib was used to demonstrate that it is expressed on the cell surface of 31 out of 33 type III strains, but only on 1 out of 25 strains representing the other three serotypes. Mouse protection tests showed that antiserum to protein Rib protects against lethal infection with three different strains expressing this antigen, including a strain representing a recently identified high virulence type III clone. Protein Rib is immunologically unrelated to the alpha and beta proteins, but shares several features with the alpha protein. Most importantly, the NH2-terminal amino acid sequences of the Rib and alpha proteins are identical at 6 out of 12 positions. In addition, both protein Rib and the alpha protein are relatively resistant to trypsin (and Rib is also resistant to pepsin) and both proteins vary greatly in size between different clinical isolates. Finally, both protein Rib and the alpha protein exhibit a regular ladderlike pattern in immunoblotting experiments, which may reflect a repetitive structure. Taken together, these data suggest that the Rib and alpha proteins are members of a family of proteins with related structure and function. Since protein Rib confers protective immunity, it may be valuable for the development of a protein vaccine against the group B Streptococcus, an encapsulated bacterium.

scholarly journals Protection from Group B Streptococcal Infection in Neonatal Mice by Maternal Immunization with Recombinant Sip Protein

2002 ◽  
Vol 70 (9) ◽  
pp. 4897-4901 ◽  
Author(s):  
Denis Martin ◽  
Stéphane Rioux ◽  
Edith Gagnon ◽  
Martine Boyer ◽  
Josée Hamel ◽  
...  
Keyword(s):  
Protective Immunity ◽  
Group B Streptococcus ◽  
Surface Protein ◽  
Neonatal Infection ◽  
Active Immunization ◽  
Infection Model ◽  
Lethal Challenge ◽  
Specific Antibodies ◽  
Pregnant Mice ◽  
Group B

ABSTRACT The protective potential of antibodies directed against group B streptococcus (GBS) Sip surface protein was determined by using the mouse neonatal infection model. Rabbit Sip-specific antibodies administered passively to pregnant mice protected their pups against a GBS lethal challenge. In addition, active immunization with purified recombinant Sip protein of female CD-1 mice induced the production of specific antibodies that also confer protection to the newborn pups against GBS strains of serotypes Ia/c, Ib, II, III, and V. These data confirm that Sip-specific antibodies can cross the placenta and conferred protective immunity against GBS infections.

scholarly journals Genetic diversity of the C protein β-antigen gene and its upstream regions within clonally related groups of type Ia and Ib group B streptococci

Microbiology ◽  
2006 ◽  
Vol 152 (3) ◽  
pp. 771-778 ◽  
Author(s):  
Noriyuki Nagano ◽  
Yukiko Nagano ◽  
Ryuichi Nakano ◽  
Ryoichi Okamoto ◽  
Matsuhisa Inoue
Keyword(s):  
Genetic Diversity ◽  
Response Regulator ◽  
Surface Protein ◽  
Premature Termination Codon ◽  
Factor H ◽  
Binding Region ◽  
Group B Streptococci ◽  
C Protein ◽  
Expression Levels ◽  
Group B

C protein β antigen (Bac), a surface protein of group B streptococci (GBS), is known to concurrently bind the Fc portion of IgA and factor H (FH). The authors' previous work has demonstrated that mRNA expression levels show diversity among clonally related strains containing genes (bac) encoding Bac, with high expression noted in invasive strains. In this study, the bac gene and upstream regions containing putative promoters, three ORFs and an IS1381 insertion sequence were characterized. Three invasive strains showed high bac expression levels and did not show any notable mutations except one strain producing Bac that was able to bind FH but not IgA. A deletion of 51 amino acid residues, including part of the Bac IgA-binding region, was identified and hypothesized to contribute to the loss of the IgA-binding ability of this strain. A vaginal strain that showed somewhat higher bac expression levels and produced Bac lacking immunoreactivity contained an 11 bp deletion, which generated a premature termination codon, in the region preceding the IgA-binding region. In another vaginal strain that did not express bac, disruption of the upstream ORFs of the sensor histidine kinase and DNA-binding response regulator, due to frameshift mutations, was noted although it is not known whether these proteins directly affect bac expression levels. An IS1381 insertion into the promoter region was found in another vaginal strain that showed low expression levels and produced Bac with a significantly larger proline-rich repeat region. These results demonstrate considerable genetic diversity of the bac and upstream regions of invasive and noninvasive GBS, which may contribute to the variability of bac expression levels among those strains.

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