scholarly journals Expression of Non-Native Genes in a Surrogate Host Organism

10.5772/31923 ◽  
2012 ◽  
Author(s):  
Dan Close ◽  
Tingting Xu ◽  
Abby Smartt ◽  
Sarah Price ◽  
Steven Ripp ◽  
...  
Keyword(s):  
Host Organism ◽  
Surrogate Host

POSSIBILITIES OF BIOLOGICAL AND MATHEMATICAL MODELING OF THE INFECTION CAUSED BY EPSTEIN–BARR VIRUS

2020 ◽  
Vol 99 (6) ◽  
pp. 226-231
Author(s):  
A.V. Permyakova ◽  
◽  
A.V. Sazhin ◽  
E.V. Melekhina ◽  
A.V. Gorelov ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Immune Regulation ◽  
Epstein Barr Virus ◽  
Virus Isolation ◽  
Biological Fluids ◽  
Infection Process ◽  
Host Organism ◽  
Barr Virus ◽  
Virus Excretion ◽  
Epstein Barr

The review presents the existing biological and mathematical models of the infection process caused by the Epstein–Barr virus. The existence of the Epstein–Barr virus in the host organism can be described by a model representing a cycle of six consecutive stages, each of them has its own independent variant of immune regulation. The phenomenon of virus excretion in biological fluids, in particular, in saliva, is modeled using differential equations. Usage of mathematical modeling allows us to supplement existing knowledge about the pathogenesis of the infectious process caused by the Epstein–Barr virus, as well as to determine threshold levels of virus isolation in non-sterile environments for the diagnosis of active forms of infection.

scholarly journals Heterodimer Formation of the Homodimeric ABC Transporter OpuA

2021 ◽  
Vol 22 (11) ◽  
pp. 5912
Author(s):  
Patricia Alvarez-Sieiro ◽  
Hendrik R. Sikkema ◽  
Bert Poolman
Keyword(s):  
Abc Transporter ◽  
Conformational Dynamics ◽  
Host Organism ◽  
Affinity Tag ◽  
Practical Applications ◽  
Fundamental Research ◽  
Protein Multimerization ◽  
Biochemical Analyses

Many proteins have a multimeric structure and are composed of two or more identical subunits. While this can be advantageous for the host organism, it can be a challenge when targeting specific residues in biochemical analyses. In vitro splitting and re-dimerization to circumvent this problem is a tedious process that requires stable proteins. We present an in vivo approach to transform homodimeric proteins into apparent heterodimers, which then can be purified using two-step affinity-tag purification. This opens the door to both practical applications such as smFRET to probe the conformational dynamics of homooligomeric proteins and fundamental research into the mechanism of protein multimerization, which is largely unexplored for membrane proteins. We show that expression conditions are key for the formation of heterodimers and that the order of the differential purification and reconstitution of the protein into nanodiscs is important for a functional ABC-transporter complex.

scholarly journals Novel Virulent Bacteriophages Infecting Mediterranean Isolates of the Plant Pest Xylella fastidiosa and Xanthomonas albilineans

Viruses ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 725
Author(s):  
Fernando Clavijo-Coppens ◽  
Nicolas Ginet ◽  
Sophie Cesbron ◽  
Martial Briand ◽  
Marie-Agnès Jacques ◽  
...  
Keyword(s):  
Phage Therapy ◽  
Xylella Fastidiosa ◽  
Infected Plant ◽  
Mediterranean Area ◽  
Genomic Features ◽  
Phylogeny Analysis ◽  
Plant Pest ◽  
European Regulations ◽  
Surrogate Host

Xylella fastidiosa (Xf) is a plant pathogen causing significant losses in agriculture worldwide. Originating from America, this bacterium caused recent epidemics in southern Europe and is thus considered an emerging pathogen. As the European regulations do not authorize antibiotic treatment in plants, alternative treatments are urgently needed to control the spread of the pathogen and eventually to cure infected crops. One such alternative is the use of phage therapy, developed more than 100 years ago to cure human dysentery and nowadays adapted to agriculture. The first step towards phage therapy is the isolation of the appropriate bacteriophages. With this goal, we searched for phages able to infect Xf strains that are endemic in the Mediterranean area. However, as Xf is truly a fastidious organism, we chose the phylogenetically closest and relatively fast-growing organism X. albineans as a surrogate host for the isolation step. Our results showed the isolation from various sources and preliminary characterization of several phages active on different Xf strains, namely, from the fastidiosa (Xff), multiplex (Xfm), and pauca (Xfp) subspecies, as well as on X. albilineans. We sequenced their genomes, described their genomic features, and provided a phylogeny analysis that allowed us to propose new taxonomic elements. Among the 14 genomes sequenced, we could identify two new phage species, belonging to two new genera of the Caudoviricetes order, namely, Usmevirus (Podoviridae family) and Subavirus (Siphoviridae family). Interestingly, no specific phages could be isolated from infected plant samples, whereas one was isolated from vector insects captured in a contaminated area, and several from surface and sewage waters from the Marseille area.

scholarly journals Nematode Hsp90: highly conserved but functionally diverse

Parasitology ◽  
2014 ◽  
Vol 141 (9) ◽  
pp. 1203-1215 ◽  
Author(s):  
VICTORIA GILLAN ◽  
EILEEN DEVANEY
Keyword(s):  
Life Cycle ◽  
Heat Shock Protein 90 ◽  
Ecological Niches ◽  
Actual Number ◽  
Host Organism ◽  
Free Living ◽  
Parasitic Species ◽  
Free Living Nematode ◽  
Functionally Diverse

SUMMARYNematodes are amongst the most successful and abundant organisms on the planet with approximately 30 000 species described, although the actual number of species is estimated to be one million or more. Despite sharing a relatively simple and invariant body plan, there is considerable diversity within the phylum. Nematodes have evolved to colonize most ecological niches, and can be free-living or can parasitize plants or animals to the detriment of the host organism. In this review we consider the role of heat shock protein 90 (Hsp90) in the nematode life cycle. We describe studies on Hsp90 in the free-living nematode Caenorhabditis elegans and comparative work on the parasitic species Brugia pahangi, and consider whether a dependence upon Hsp90 can be exploited for the control of parasitic species.

Dictyostelium discoideum as a surrogate host–microbe model for antivirulence screening in Pseudomonas aeruginosa PAO1

2016 ◽  
Vol 47 (5) ◽  
pp. 403-409 ◽  
Author(s):  
Catalina Bravo-Toncio ◽  
Javiera A. Álvarez ◽  
Francisca Campos ◽  
Javiera Ortíz-Severín ◽  
Macarena Varas ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Dictyostelium Discoideum ◽  
Pseudomonas Aeruginosa Pao1 ◽  
Surrogate Host

scholarly journals Determination of amino acids misincorporation in recombinant protein by mass spectrometry

2013 ◽  
Vol 42 (1) ◽  
pp. 11-19 ◽  
Author(s):  
MZ Alam ◽  
L Regioneiri ◽  
MAS Santos
Keyword(s):  
Mass Spectrometry ◽  
Amino Acids ◽  
Recombinant Protein ◽  
Gene Fusion ◽  
Aminoglycoside Antibiotic ◽  
Protein Functionality ◽  
Lacz Gene ◽  
Host Organism ◽  
E Coli

The synthesis of protein according to genetic code of a gene determines the basis of life and a stable proteome is necessary for cell homeostatis. However, errors occur naturally during translation of protein from its mRNA, which varies from 10-3 to 10-4 per codon. These errors are more frequent in recombinant protein overexpressed in heterologous hosts and affect protein functionality. The increasing amount of nonfunctional protein is often related to mistranslation of a gene under stress. In the present study, Saccharomyces cerevisiae as a host organism to overexpress E. coli lacZ gene fusion with GST to quantify misincorporation of amino acid in GST-? galactosidase recombinant protein. The yeast was treated with various stressors such as ethanol, chromium (CrO3), and aminoglycoside antibiotic - geneticin (G418) to induce protein aggregation. The misincorporation of amino acids was studied in soluble protein fractions by mass-spectrometry to determine how much misincorporation occur. We found that under experimental stress conditions the misincorporation of amino acids ranges from 5.6 ×10-3 to 8 × 10-3, which represents 60-80 fold higher than reported level. DOI: http://dx.doi.org/10.3329/bjas.v42i1.15760 Bang. J. Anim. Sci. 2013. 42 (1): 11-19

An aqueous two-phase system to pre-purify a heterologously produced siderophore

TECHNOLOGY ◽  
2016 ◽  
Vol 04 (03) ◽  
pp. 135-138
Author(s):  
Mahmoud Kamal Ahmadi ◽  
Samar Fawaz ◽  
Blaine A. Pfeifer
Keyword(s):  
Escherichia Coli ◽  
Natural Products ◽  
Cell Growth ◽  
Complex Nature ◽  
Phase System ◽  
Heterologous Production ◽  
Two Phase ◽  
Aqueous Two Phase System ◽  
Purification System ◽  
Surrogate Host

Natural products span broad activities and applications; however, their access and production are often limited by native cellular sources. As a result, the heterologous production of a siderophore termed yersiniabactin (Ybt) was completed using the surrogate host Escherichia coli. Post-production and purification steps are complicated by the complex nature of most media used for cell growth, prompting the development in this work of an aqueous two-phase pre-purification system capable of rapidly and simply enhancing the concentration of the target Ybt compound.

scholarly journals Identifying ligand-binding specificity of the oligopeptide receptor OppA from Bifidobacterium longum KACC91563 by Structure-based molecular modeling

2020 ◽  
Author(s):  
Han-Ha Chai ◽  
Young Ran Kim ◽  
Jun-Sang Ham ◽  
Tae-Hun Kim ◽  
Dajeong Lim
Keyword(s):  
Molecular Modeling ◽  
Structure Function ◽  
Binding Site ◽  
Bifidobacterium Longum ◽  
Peptide Binding ◽  
Binding Pocket ◽  
Host Organism ◽  
Specialized Structure ◽  
Function Relationship ◽  
The Relationship

Abstract Background: The OppA receptor as a ATP-binding cassette (ABC) transporter plays key roles in protecting host organism and transport nutrients across the intestine by the oligopeptide transporter from symbiotic bacteria directs maturation of the host immune system. Among lactic acid bacteria, Bifidobacterium longum KACC91563, isolated from fecal samples of healthy Korean neonates, has the capability to alleviate food allergy effects. The extracellular OppA receptor from gram-positive Bifidobacterium longum KACC91563 translocate nutrients-peptides from the outside environment of intestinal tract to the inside of the symbiotic cell, as a peptide importer. Hence, it was attempting to explicate the relationship between the substrate’s specificity from the OppA importer and the probiotic effects of B. logum KACC91563 in the host intestine. The probiotic effects of B. logum KACC91563 were attributed to the enhancement of the epithelial barrier by several different strain sepcific ways to prevent the strong adhesion of pathogens. The specialized structure-function relationship from the OppA importer could provide the abstract of substrate specificity into unique immunological properties of that the host organism.Results: In the study, we characterized the extracellular OppA importer from B. longum KACC91563 of intestinal microbiome by various protein structure-based modelings in silico. Structural characterization by conserved 5 patches and 4 functional motifs from specific trace residues of the OppA importer. The hydrate surface of the binding site had been decipted by specific trace residues of the OppA that trace residues of Thr58, Lys185, Trp443, and Tyr447, which were characterized in highly exposed hydrophobic binding pocket by its aggregation prones. Therefore, the spatial aggregation propensity in the binding site of the extracellular OppA importer plays a vital role in the specific interaction determinant for peptide binding. In addition, alanine mutation energy values allowed for the virtual determination of the relationships between the energy effects of the peptide binding site mutation on the transporter structural stability, the peptide binding affinity, and the transporter-related peptide substrate selectivity from OppA importer. In particular, distinctive seven pharmacophoric features comprised of two H-bonding donor(P1), three H-bonding acceptor(P8), and two hydrophobic points (P5 and P8) matched the the OppA receptor-peptide ligand interactions within their binding pocket structure. There are distinct interactions to fix the positions of the N(P1) and C(P8) termini of the complex of OppA-peptide from B. longum KACC91563 such as side chain-specific interactions with the OppA, compared to that of the Lactococcus latis (L. lactics) OppA.Conclusions: The specialized structure-function relationship from the OppA import could provide the abstract of substrate specificity into unique immunological properties of the host organism by stucutre-based molecular modeling. In the current study, we attempted explication of the relationship between the substrate’s specificity from the OppA importer and the probiotic effects of B. longum KACC91563 in the host intestine based on the structure-function perspectives of the OppA importer. Moreover, functional characterization of solute-binding proteins (such as 15 cell wall proteins and 20 extracellular proteins) on the B. longum KACC91563 genome will lead to insight of key switch for substate’s metabolism into reprogramming immune responses in the host intestine.

scholarly journals The determination of microscopic fungi from Chestnut (Castanea sativa Mill.) fruits, leaves, crust and pollen

2010 ◽  
Vol 58 (4) ◽  
pp. 73-78 ◽  
Author(s):  
Miroslava Kačániová ◽  
Janka Sudzinová ◽  
Miriam Kádasi-Horáková ◽  
Magdaléna Valšíková ◽  
Stanislav Kráčmar
Keyword(s):  
Castanea Sativa ◽  
Host Organism ◽  
Microscopic Fungi ◽  
Castanea Sativa Mill

The plant-microbial interactive relations with respect to determination of the mycoflora of theCastanea sativaMill. nuts, crust, leaves and pollen and their effect on the host organism in four Slovak regions were studied. In the experiments were isolated 7 genera and 10 species of microscopic fungi from the nut, crust and leaves. It was found, that isolates from theCastanea sativaMill. pollen were represented by 8 genera and 11 species of microscopic fungi.Alternaria,Cladosporium,MucorandRhizopusappeared to be the most frequently occurring genera of nuts, leaves and crust.Acremonium,Alternaria,Cladosporium,Fusarium,PenicilliumandTrichodermaare the most frequently fungi of pollen. On the base of further taxonomic determination from the generaAspergilluswere isolated and identified representatives of speciesA. flavus,A. fumigatus,A. ochraceus,A. terreusandA. versicolor. From the generaFusariumwas isolatedF. oxysporumand fromPenicilliumgenera were isolatedP. crustosumandP. glabrum. It is necessary to underline that the isolated generaAspergillus,FusariumandPenicilliumare considered as the most important producers of mycotoxins.

Sign in / Sign up

Export Citation Format

Share Document