scholarly journals Structural and functional characterization of SiiA, an auxiliary protein from the SPI4‐encoded type 1 secretion system from Salmonella enterica

2019 ◽  
Vol 112 (5) ◽  
pp. 1403-1422 ◽  
Author(s):  
Peter Kirchweger ◽  
Sigrid Weiler ◽  
Claudia Egerer‐Sieber ◽  
Anna‐Theresa Blasl ◽  
Stefanie Hoffmann ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Functional Characterization ◽  
Secretion System ◽  
Auxiliary Protein

scholarly journals Structural and Functional Characterization of ScsC, a Periplasmic Thioredoxin-Like Protein from Salmonella enterica Serovar Typhimurium

2013 ◽  
Vol 19 (13) ◽  
pp. 1494-1506 ◽  
Author(s):  
Mark Shepherd ◽  
Begoña Heras ◽  
Maud E. S. Achard ◽  
Gordon J. King ◽  
M. Pilar Argente ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Salmonella Enterica Serovar Typhimurium ◽  
Functional Characterization ◽  
Serovar Typhimurium

scholarly journals Characteristics of a Series of Three Bacteriophages Infecting Salmonella enterica Strains

2020 ◽  
Vol 21 (17) ◽  
pp. 6152 ◽  
Author(s):  
Katarzyna Kosznik-Kwaśnicka ◽  
Karolina Ciemińska ◽  
Michał Grabski ◽  
Łukasz Grabowski ◽  
Marcin Górniak ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Phage Therapy ◽  
Functional Characterization ◽  
Bacterial Biofilm ◽  
Host Cells ◽  
Detailed Characterization ◽  
Food Protection ◽  
Adsorption Rates ◽  
Potential Use

Molecular and functional characterization of a series of three bacteriophages, vB_SenM-1, vB_SenM-2, and vB_SenS-3, infecting various Salmonella enterica serovars and strains is presented. All these phages were able to develop lytically while not forming prophages. Moreover, they were able to survive at pH 3. The phages revealed different host ranges within serovars and strains of S. enterica, different adsorption rates on host cells, and different lytic growth kinetics at various temperatures (in the range of 25 to 42 °C). They efficiently reduced the number of cells in the bacterial biofilm and decreased the biofilm mass. Whole genome sequences of these phages have been determined and analyzed, including their phylogenetic relationships. In conclusion, we have demonstrated detailed characterization of a series of three bacteriophages, vB_SenM-1, vB_SenM-2, and vB_SenS-3, which reveal favorable features in light of their potential use in phage therapy of humans and animals, as well as for food protection purposes.

scholarly journals Identification and functional characterization of CD8+ T regulatory cells in type 1 diabetes patients

PLoS ONE ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. e0210839 ◽  
Author(s):  
Marsha Pellegrino ◽  
Antonino Crinò ◽  
Manuela M. Rosado ◽  
Alessandra Fierabracci
Keyword(s):  
Type 1 Diabetes ◽  
T Regulatory Cells ◽  
Functional Characterization ◽  
Regulatory Cells ◽  
Diabetes Patients

scholarly journals Functional characterization of naturally occurring NR3C2 gene mutations in Italian patients suffering from pseudohypoaldosteronism type 1

2007 ◽  
Vol 156 (2) ◽  
pp. 249-256 ◽  
Author(s):  
Antonio Balsamo ◽  
Alessandro Cicognani ◽  
Monia Gennari ◽  
Wolfgang G Sippell ◽  
Soara Menabò ◽  
...  
Keyword(s):  
Receptor Gene ◽  
Functional Characterization ◽  
Clinical Signs ◽  
Gene Mutations ◽  
Ethnic Origin ◽  
Snp Markers ◽  
Italian Population ◽  
Pseudohypoaldosteronism Type

Objective: The renal form of pseudohypoaldosteronism type 1 (PHA1) is a rare disease caused by mutations in the human mineralocorticoid receptor gene (NR3C2). Design: Aim of the study was to analyze the NR3C2 gene in three Italian patients with clinical signs of renal PHA1 and to evaluate the distribution of the -2G > C, c.538A > G, and c.722C > T single nucleotide polymorphism (SNP) pattern in the PHA1 patients and in 90 controls of the same ethnic origin. Methods: Analysis of the NR3C2 gene sequence and of the polymorphic SNP markers. Functional characterization of the detected novel NR3C2 mutations utilizing aldosterone-binding assays and reporter gene transactivation assays. Results: One novel nonsense (Y134X) and one novel frameshift (2125delA) mutation were detected. They exhibited no aldosterone binding and no transactivation abilities. No mutation was detected in the third patient. Haploinsufficiency of NR3C2 was ruled out by microsatellite analysis in this patient. The c.722T SNP was detected in 97% of alleles in the Italian population which is significantly different from the general German or US population. Conclusions: Molecular analysis of the NR3C2 gene in PHA1 patients is warranted to detect novel mutations in order to clarify the underlying genetic cause, which may extend the insight into relevant functional regions of the hMR protein. The effect the different distribution of the c.722T SNP is not clear to date. Further studies are necessary to provide evidence as to a possible advantage of a less sensitive hMR in southern countries.

scholarly journals Functional Characterization of EscK (Orf4), a Sorting Platform Component of the Enteropathogenic Escherichia coli Injectisome

2016 ◽  
Vol 199 (1) ◽  
Author(s):  
Eduardo Soto ◽  
Norma Espinosa ◽  
Miguel Díaz-Guerrero ◽  
Meztlli O. Gaytán ◽  
José L. Puente ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Type Iii Secretion ◽  
Diarrheal Disease ◽  
Functional Characterization ◽  
Type Iii Secretion System ◽  
Secretion System ◽  
Effector Proteins ◽  
Content Type ◽  
Enterocyte Effacement

ABSTRACT The type III secretion system (T3SS) is a supramolecular machine used by many bacterial pathogens to translocate effector proteins directly into the eukaryotic host cell cytoplasm. Enteropathogenic Escherichia coli (EPEC) is an important cause of infantile diarrheal disease in underdeveloped countries. EPEC virulence relies on a T3SS encoded within a chromosomal pathogenicity island known as the locus of enterocyte effacement (LEE). In this work, we pursued the functional characterization of the LEE-encoded protein EscK (previously known as Orf4). We provide evidence indicating that EscK is crucial for efficient T3S and belongs to the SctK (OrgA/YscK/MxiK) protein family, whose members have been implicated in the formation of a sorting platform for secretion of T3S substrates. Bacterial fractionation studies showed that EscK localizes to the inner membrane independently of the presence of any other T3SS component. Combining yeast two-hybrid screening and pulldown assays, we identified an interaction between EscK and the C-ring/sorting platform component EscQ. Site-directed mutagenesis of conserved residues revealed amino acids that are critical for EscK function and for its interaction with EscQ. In addition, we found that T3S substrate overproduction is capable of compensating for the absence of EscK. Overall, our data suggest that EscK is a structural component of the EPEC T3SS sorting platform, playing a central role in the recruitment of T3S substrates for boosting the efficiency of the protein translocation process. IMPORTANCE The type III secretion system (T3SS) is an essential virulence determinant for enteropathogenic Escherichia coli (EPEC) colonization of intestinal epithelial cells. Multiple EPEC effector proteins are injected via the T3SS into enterocyte cells, leading to diarrheal disease. The T3SS is encoded within a genomic pathogenicity island termed the locus of enterocyte effacement (LEE). Here we unravel the function of EscK, a previously uncharacterized LEE-encoded protein. We show that EscK is central for T3SS biogenesis and function. EscK forms a protein complex with EscQ, the main component of the cytoplasmic sorting platform, serving as a docking site for T3S substrates. Our results provide a comprehensive functional analysis of an understudied component of T3SSs.

scholarly journals Functional Characterization of OXYL, A SghC1qDC LacNAc-specific Lectin from The Crinoid Feather Star Anneissia Japonica

Marine Drugs ◽  
2019 ◽  
Vol 17 (2) ◽  
pp. 136 ◽  
Author(s):  
Imtiaj Hasan ◽  
Marco Gerdol ◽  
Yuki Fujii ◽  
Yasuhiro Ozeki
Keyword(s):  
Human Cancer ◽  
Functional Characterization ◽  
Mapk Signaling ◽  
Carbohydrate Binding ◽  
Human Cancer Cell Lines ◽  
Intronless Genes ◽  
Feather Star

We identified a lectin (carbohydrate-binding protein) belonging to the complement 1q(C1q) family in the feather star Anneissia japonica (a crinoid pertaining to the phylum Echinodermata). The combination of Edman degradation and bioinformatics sequence analysis characterized the primary structure of this novel lectin, named OXYL, as a secreted 158 amino acid-long globular head (sgh)C1q domain containing (C1qDC) protein. Comparative genomics analyses revealed that OXYL pertains to a family of intronless genes found with several paralogous copies in different crinoid species. Immunohistochemistry assays identified the tissues surrounding coelomic cavities and the arms as the main sites of production of OXYL. Glycan array confirmed that this lectin could quantitatively bind to type-2 N-acetyllactosamine (LacNAc: Galβ1-4GlcNAc), but not to type-1 LacNAc (Galβ1-3GlcNAc). Although OXYL displayed agglutinating activity towards Pseudomonas aeruginosa, it had no effect on bacterial growth. On the other hand, it showed a significant anti-biofilm activity. We provide evidence that OXYL can adhere to the surface of human cancer cell lines BT-474, MCF-7, and T47D, with no cytotoxic effect. In BT-474 cells, OXYL led to a moderate activation of the p38 kinase in the MAPK signaling pathway, without affecting the activity of caspase-3. Bacterial agglutination, anti-biofilm activity, cell adhesion, and p38 activation were all suppressed by co-presence of LacNAc. This is the first report on a type-2 LacNAc-specific lectin characterized by a C1q structural fold.

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