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International Journal of Molecular... Jan 2024The Sm protein superfamily includes Sm, like-Sm (Lsm), and Hfq found in the , , and domains. Archaeal Lsm proteins have been shown to bind sRNAs and are probably...
The Sm protein superfamily includes Sm, like-Sm (Lsm), and Hfq found in the , , and domains. Archaeal Lsm proteins have been shown to bind sRNAs and are probably involved in various cellular processes, suggesting a similar function in regulating sRNAs by Hfq in bacteria. Moreover, archaeal Lsm proteins probably represent the ancestral Lsm domain from which eukaryotic Sm proteins have evolved. In this work, was used as a model organism because it has been widely used to investigate the nitrogen cycle and its regulation in Haloarchaea. Predicting this protein's secondary and tertiary structures has resulted in a three-dimensional model like the solved Lsm protein structure of . To obtain information on the oligomerization state of the protein, homologous overexpression and purification by means of molecular exclusion chromatography have been performed. The results show that this protein can form hexameric complexes, which can aggregate into 6 or 12 hexameric rings depending on the NaCl concentration and without RNA. In addition, the study of transcriptional expression via microarrays has allowed us to obtain the target genes regulated by the Lsm protein under nutritional stress conditions: nitrogen or carbon starvation. Microarray analysis has shown the first universal stress proteins (USP) in this microorganism that mediate survival in situations of nitrogen deficiency.
Topics: Haloferax mediterranei; Archaeal Proteins; Heat-Shock Proteins; Archaea; Nitrogen
PubMed: 38203750
DOI: 10.3390/ijms25010580 -
Virology Journal Jan 2024Proteins, RNA, DNA, lipids, and carbohydrates are only some of the molecular components found in exosomes released by tumor cells. They play an essential role in healthy... (Review)
Review
Proteins, RNA, DNA, lipids, and carbohydrates are only some of the molecular components found in exosomes released by tumor cells. They play an essential role in healthy and diseased cells as messengers of short- and long-distance intercellular communication. However, since exosomes are released by every kind of cell and may be found in blood and other bodily fluids, they may one day serve as biomarkers for a wide range of disorders. In many pathological conditions, including cancer, inflammation, and infection, they play a role. It has been shown that the biogenesis of exosomes is analogous to that of viruses and that the exosomal cargo plays an essential role in the propagation, dissemination, and infection of several viruses. Bidirectional modulation of the immune response is achieved by the ability of exosomes associated with viruses to facilitate immunological escape and stimulate the body's antiviral immune response. Recently, exosomes have received a lot of interest due to their potential therapeutic use as biomarkers for viral infections such as human immunodeficiency virus (HIV), Hepatitis B virus (HBV), Hepatitis C virus (HCV), Epstein-Barr virus (EBV), and SARS-CoV-2. This article discusses the purification procedures and detection techniques for exosomes and examines the research on exosomes as a biomarker of viral infection.
Topics: Humans; Exosomes; Herpesvirus 4, Human; Epstein-Barr Virus Infections; Cell Communication; Biomarkers
PubMed: 38291452
DOI: 10.1186/s12985-024-02301-5 -
Food Chemistry Aug 2024Edible insects represent a great alternative protein source but food neophobia remains the main barrier to consumption. However, the incorporation of insects as...
Influence of the processing on composition, protein structure and techno-functional properties of mealworm protein concentrates produced by isoelectric precipitation and ultrafiltration/diafiltration.
Edible insects represent a great alternative protein source but food neophobia remains the main barrier to consumption. However, the incorporation of insects as protein-rich ingredients, such as protein concentrates, could increase acceptance. In this study, two methods, isoelectric precipitation and ultrafiltration-diafiltration, were applied to produce mealworm protein concentrates, which were compared in terms of composition, protein structure and techno-functional properties. The results showed that the protein content of the isoelectric precipitation concentrate was higher than ultrafiltration-diafiltration (80 versus 72%) but ash (1.91 versus 3.82%) and soluble sugar (1.43 versus 8.22%) contents were lower. Moreover, the protein structure was affected by the processing method, where the ultrafiltration-diafiltration concentrate exhibited a higher surface hydrophobicity (493.5 versus 106.78 a.u) and a lower denaturation temperature (161.32 versus 181.44 °C). Finally, the ultrafiltration-diafiltration concentrate exhibited higher solubility (87 versus 41%) and emulsifying properties at pH 7 compared to the concentrate obtained by isoelectric precipitation.
Topics: Ultrafiltration; Animals; Hydrophobic and Hydrophilic Interactions; Insect Proteins; Tenebrio; Chemical Precipitation; Solubility; Hydrogen-Ion Concentration; Food Handling
PubMed: 38581785
DOI: 10.1016/j.foodchem.2024.139177 -
Journal of Global Antimicrobial... Jun 2024
Topics: beta-Lactamases; Bacterial Proteins; Anti-Bacterial Agents; Microbial Sensitivity Tests; Humans; Chloramphenicol; Enterobacteriaceae; Carbapenem-Resistant Enterobacteriaceae; Enterobacteriaceae Infections
PubMed: 38417738
DOI: 10.1016/j.jgar.2024.02.003 -
Nucleic Acids Research Jan 2024With the progress of structural biology, the Protein Data Bank (PDB) has witnessed rapid accumulation of experimentally solved protein structures. Since many structures...
With the progress of structural biology, the Protein Data Bank (PDB) has witnessed rapid accumulation of experimentally solved protein structures. Since many structures are determined with purification and crystallization additives that are unrelated to a protein's in vivo function, it is nontrivial to identify the subset of protein-ligand interactions that are biologically relevant. We developed the BioLiP2 database (https://zhanggroup.org/BioLiP) to extract biologically relevant protein-ligand interactions from the PDB database. BioLiP2 assesses the functional relevance of the ligands by geometric rules and experimental literature validations. The ligand binding information is further enriched with other function annotations, including Enzyme Commission numbers, Gene Ontology terms, catalytic sites, and binding affinities collected from other databases and a manual literature survey. Compared to its predecessor BioLiP, BioLiP2 offers significantly greater coverage of nucleic acid-protein interactions, and interactions involving large complexes that are unavailable in PDB format. BioLiP2 also integrates cutting-edge structural alignment algorithms with state-of-the-art structure prediction techniques, which for the first time enables composite protein structure and sequence-based searching and significantly enhances the usefulness of the database in structure-based function annotations. With these new developments, BioLiP2 will continue to be an important and comprehensive database for docking, virtual screening, and structure-based protein function analyses.
Topics: Algorithms; Binding Sites; Databases, Protein; Ligands; Proteins
PubMed: 37522378
DOI: 10.1093/nar/gkad630 -
Nutrients Apr 2024As gluten may trigger gastrointestinal disorders (GIDs), its presence or absence in the diet can change the diversity and proportion of gut microbiota. The effects of... (Randomized Controlled Trial)
Randomized Controlled Trial
As gluten may trigger gastrointestinal disorders (GIDs), its presence or absence in the diet can change the diversity and proportion of gut microbiota. The effects of gluten after six weeks of a double-blind, placebo-controlled intervention with a gluten-free diet (GFD) were studied in participants with GIDs suffering from migraines and atopic dermatitis (n = 46). Clinical biomarkers, digestive symptoms, stool, the Migraine Disability Assessment questionnaire, and zonulin levels were analyzed. Next-generation sequencing was used to amplify the 16S rRNA gene of bacteria and the internal transcribed spacer (ITS) regions of fungi. The GFD increased Chao1 fungal diversity after the intervention, while the fungal composition showed no changes. Bacterial diversity and composition remained stable, but a positive association between bacterial and fungal Chao1 diversity and a negative association between Dothideomycetes and were observed. GIDs decreased in both groups and migraines improved in the placebo group. Our findings may aid the development of GID treatment strategies.
Topics: Humans; Migraine Disorders; Gastrointestinal Microbiome; Female; Male; Gastrointestinal Diseases; Adult; Double-Blind Method; Glutens; Middle Aged; Diet, Gluten-Free; Dermatitis, Atopic; Feces; Bacteria; Fungi; RNA, Ribosomal, 16S; Protein Precursors; Haptoglobins
PubMed: 38674918
DOI: 10.3390/nu16081228 -
Biomolecules Mar 2024The identification of the hormone erythropoietin (EPO), which regulates red blood cell production, and its development into a pharmaceutical-grade product to treat... (Review)
Review
The identification of the hormone erythropoietin (EPO), which regulates red blood cell production, and its development into a pharmaceutical-grade product to treat anemia has been not only a herculean task but it has also been the first of its kind. As with all the successes, it had "winners" and "losers", but its history is mostly told by the winners who, over the years, have published excellent scientific and divulgate summaries on the subject, some of which are cited in this review. In addition, "success" is also due to the superb and dedicated work of numerous "crew" members, who often are under-represented and under-recognized when the story is told and often have several "dark sides" that are not told in the polished context of most reviews, but which raised the need for the development of the current legislation on biotherapeutics. Although I was marginally involved in the clinical development of erythropoietin, I have known on a personal basis most, if not all, the protagonists of the saga and had multiple opportunities to talk with them on the drive that supported their activities. Here, I will summarize the major steps in the development of erythropoietin as the first bioproduct to enter the clinic. Some of the "dark sides" will also be mentioned to emphasize what a beautiful achievement of humankind this process has been and how the various unforeseen challenges that emerged were progressively addressed in the interest of science and of the patient's wellbeing.
Topics: Animals; Humans; Anemia; Erythropoietin; History, 20th Century; History, 21st Century
PubMed: 38672425
DOI: 10.3390/biom14040408 -
Acta Tropica Jun 2024Cervids are highly exposed to ticks, however, their role in the life cycle of these rickettsiae has not been fully elucidated. Given the expanding distribution and...
Cervids are highly exposed to ticks, however, their role in the life cycle of these rickettsiae has not been fully elucidated. Given the expanding distribution and growing population of deer species in Portugal, coupled with their direct and indirect interactions with humans during hunting, it becomes crucial to explore their role as sentinels and potential reservoirs of Rickettsia. The present investigation aimed to detect and evaluate exposure to Rickettsia in free-living deer from Portugal. Blood samples (n = 77) were collected from hunted game animals (red deer and fallow deer) from different areas throughout Portugal (Idanha-a-Nova, Monte Fidalgo, Montalvão and Arraiolos) and sera were tested by immunofluorescence assay, to detect antibodies. Additionally, blood DNA samples were screened for SFGR by nested-polymerase chain reaction targeting a fragment of the outer membrane protein B (ompB) gene, as well as for Anaplasma and Ehrlichia spp. targeting the 16S rRNA gene. Thirty-five per cent (25 deer and two fallow deer) tested positive (sera with a titer ≥1:64) for IgG antibodies against Rickettsia conorii. No rickettsial DNA was detected by PCR for the ompB gene, and all DNA samples tested negative for Anaplasma and Ehrlichia. As far as we know, this study is the first screening of cervid species in Portugal for Rickettsia antibodies. The findings suggest that these animals serve as useful sentinel indicators for the circulation of rickettsiae, offering a complementary perspective to studies focused on ticks. The increasing numbers of hunted deer in Portugal and the potential zoonotic features of Rickettsia spp. highlight the importance of continued surveillance directed at tick-borne diseases, especially those involving wild animals.
Topics: Animals; Portugal; Deer; Antibodies, Bacterial; Rickettsia; Rickettsia Infections; Sentinel Species; DNA, Bacterial; Immunoglobulin G; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Anaplasma; Ehrlichia; Rickettsia conorii; Bacterial Outer Membrane Proteins; Male
PubMed: 38565332
DOI: 10.1016/j.actatropica.2024.107202 -
Journal of Chromatography. B,... May 2024Adiponectin, a crucial protein hormone originating from adipose tissue, regulates key metabolic processes, including lipid metabolism, mitochondrial activity, and...
Adiponectin, a crucial protein hormone originating from adipose tissue, regulates key metabolic processes, including lipid metabolism, mitochondrial activity, and insulin sensitivity. These pleiotropic roles of adiponectin, along with its inverse correlation with metabolic disorders such as obesity, type II diabetes, and atherosclerosis, establish this protein as a potential therapeutic target. However, due to this complexity, challenges have arisen in its production with a natural conformation in bacterial or mammalian expression systems, hindering clinical translation. Furthermore, while inducers for adiponectin secretion or chemical agonists targeting adiponectin receptors have shown promise in laboratory settings, clinical studies with these agents have not yet been conducted. This study proposes a method for isolating and purifying natural high molecular weight (HMW) adiponectin from discarded plasma fractions during the conventional pharmaceutical protein manufacturing process. The process involved Cohn-Oncley fractionation, initial chromatography using reduced cellufine formyl, and subsequent purification via DEAE Sepharose chromatography. Characterization involved gel electrophoresis and biological assays on a hepatocyte cell-line. The purification process effectively captured adiponectin from the I + III paste, demonstrating that this fraction contained a significant portion of total plasma adiponectin. The two-step chromatography led to highly purified HMW adiponectin, confirmed by native-PAGE showing a 780 kDa multimeric complex. Biological assessments demonstrated normal downstream signaling, with HMW adiponectin inducing AMPK phosphorylation. This study demonstrates the feasibility of obtaining purified HMW adiponectin by repurposing plasma fractionation processes. It offers a promising avenue for the HMW adiponectin production, tapping into HMW adiponectin's therapeutic potential against metabolic disorders while optimizing plasma resource utilization in healthcare.
Topics: Humans; Adiponectin; Molecular Weight; Chromatography, Ion Exchange
PubMed: 38603890
DOI: 10.1016/j.jchromb.2024.124111 -
American Journal of Perinatology May 2024Maternal colonization with Group B (GBS) is a significant risk factor for serious neonatal morbidity. There are limited data on how the cervicovaginal (CV)...
OBJECTIVE
Maternal colonization with Group B (GBS) is a significant risk factor for serious neonatal morbidity. There are limited data on how the cervicovaginal (CV) microbiota and host immune factor β-defensin-2 might influence GBS colonization in pregnant individuals. This study sought to determine if the CV microbiota is associated with GBS colonization in pregnant individuals, and if β-defensin-2 modifies this relationship.
STUDY DESIGN
This was a secondary analysis of a prospective cohort study of pregnant individuals with singleton pregnancies who had CV microbiota specimens analyzed at 16 to 20, 20 to 24, and 24 to 28 weeks' gestation, along with a third trimester GBS rectovaginal (RV) culture ( = 492). Microbiota data were analyzed with 16S rRNA gene sequencing and classified into community state types (CSTs). Log-binomial multivariable regression was used to model associations between CST and GBS RV status and to calculate risk ratios. β-defensin-2, an immune factor known to modulate the relationship between CST and pregnancy outcomes, was examined as an effect modifier.
RESULTS
Of 492 individuals, 34.3% were GBS RV + . Compared with individuals with CST I at 16 to 20 weeks, individuals with CST IV-A and CST II had a significantly elevated relative risk of subsequent GBS RV+ status. When stratified by high and low β-defensin-2 levels, β-defensin-2 was found to be an effect modifier of the association between CST IV-A and GBS RV+ status. In individuals with low β-defensin-2 levels, CST VI-A was associated with GBS RV+ status, but among individuals with high β-defensin-2 levels, there was no such association (interaction -value = 0.03).
CONCLUSION
Pregnant individuals with CV microbiota characterized by CST IV-A and CST II had significantly elevated risk of GBS RV colonization in the third trimester compared with those with CST I, and β-defensin-2 was an effect modifier of the association between CST IV-A and GBS RV+ status. Future research should investigate if manipulation of the CV microbiota can prevent GBS colonization, thereby reducing intrapartum antibiotic prophylaxis and the risks of neonatal GBS infection.
KEY POINTS
· The relationship between the CV microbiota and GBS RV colonization is unknown.. · A Lactobacillus-deficient, anaerobic rich vaginal community, CST IV-A, is associated with increased risk of GBS RV colonization.. · β-defensin-2 is an effect modifier of the association between CST IV-A and GBS RV+ status..
Topics: Humans; Female; Pregnancy; Vagina; Streptococcus agalactiae; Streptococcal Infections; beta-Defensins; Prospective Studies; Adult; Pregnancy Complications, Infectious; Microbiota; Cervix Uteri; Young Adult; RNA, Ribosomal, 16S
PubMed: 37557898
DOI: 10.1055/s-0043-1772226