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Marine Drugs Jan 2021Cyanobacteria are a rich source of secondary metabolites with a vast biotechnological potential. These compounds have intrigued the scientific community due their... (Review)
Review
Cyanobacteria are a rich source of secondary metabolites with a vast biotechnological potential. These compounds have intrigued the scientific community due their uniqueness and diversity, which is guaranteed by a rich enzymatic apparatus. The ribosomally synthesized and post-translationally modified peptides (RiPPs) are among the most promising metabolite groups derived from cyanobacteria. They are interested in numerous biological and ecological processes, many of which are entirely unknown. Microviridins are among the most recognized class of ribosomal peptides formed by cyanobacteria. These oligopeptides are potent inhibitors of protease; thus, they can be used for drug development and the control of mosquitoes. They also play a key ecological role in the defense of cyanobacteria against microcrustaceans. The purpose of this review is to systematically identify the key characteristics of microviridins, including its chemical structure and biosynthesis, as well as its biotechnological and ecological significance.
Topics: Animals; Cyanobacteria; Ecology; Humans; Insect Control; Oligopeptides; Protease Inhibitors
PubMed: 33406599
DOI: 10.3390/md19010017 -
Infection and Immunity Apr 2020Peptidoglycan, the sugar-amino acid polymer that composes the bacterial cell wall, requires a significant expenditure of energy to synthesize and is highly immunogenic....
Peptidoglycan, the sugar-amino acid polymer that composes the bacterial cell wall, requires a significant expenditure of energy to synthesize and is highly immunogenic. To minimize the loss of an energetically expensive metabolite and avoid host detection, bacteria often recycle their peptidoglycan, transporting its components back into the cytoplasm, where they can be used for subsequent rounds of new synthesis. The peptidoglycan-recycling substrate binding protein (SBP) MppA, which is responsible for recycling peptidoglycan fragments in , has not been annotated for most intracellular pathogens. One such pathogen, , has a limited capacity to synthesize amino acids and therefore must obtain oligopeptides from its host cell for growth. Bioinformatics analysis suggests that the putative oligopeptide transporter OppABCDF (OppABCDF ) encodes multiple SBPs (OppA1 , OppA2 , and OppA3 ). Intracellular pathogens often encode multiple SBPs, while only one, OppA, is encoded in the operon. We hypothesized that the putative OppABCDF transporter of functions in both oligopeptide transport and peptidoglycan recycling. We coexpressed the putative SBP genes ( , , ) along with in an mutant lacking the Opp transporter and determined that all three chlamydial OppA subunits supported oligopeptide transport. We also demonstrated the functionality of the chlamydial Opp transporter in Importantly, we found that one chlamydial SBP, OppA3 , possessed dual substrate recognition properties and is capable of transporting peptidoglycan fragments (tri-diaminopimelic acid) in and in These findings suggest that evolved an oligopeptide transporter to facilitate the acquisition of oligopeptides for growth while simultaneously reducing the accumulation of immunostimulatory peptidoglycan fragments in the host cell cytosol. The latter property reflects bacterial pathoadaptation that dampens the host innate immune response to infection.
Topics: Amino Acids; Bacterial Proteins; Biological Transport; Carrier Proteins; Cell Line, Tumor; Cell Wall; Chlamydia Infections; Chlamydia trachomatis; Cytosol; Escherichia coli; Genes, Bacterial; HeLa Cells; Humans; Immunity, Innate; Membrane Transport Proteins; Oligopeptides; Operon; Peptidoglycan
PubMed: 32094256
DOI: 10.1128/IAI.00086-20 -
Biomolecules Jun 2014Proteasomes are key proteases involved in a variety of processes ranging from the clearance of damaged proteins to the presentation of antigens to CD8+ T-lymphocytes.... (Review)
Review
Proteasomes are key proteases involved in a variety of processes ranging from the clearance of damaged proteins to the presentation of antigens to CD8+ T-lymphocytes. Which cleavage sites are used within the target proteins and how fast these proteins are degraded have a profound impact on immune system function and many cellular metabolic processes. The regulation of proteasome activity involves different mechanisms, such as the substitution of the catalytic subunits, the binding of regulatory complexes to proteasome gates and the proteasome conformational modifications triggered by the target protein itself. Mathematical models are invaluable in the analysis; and potentially allow us to predict the complex interactions of proteasome regulatory mechanisms and the final outcomes of the protein degradation rate and MHC class I epitope generation. The pioneering attempts that have been made to mathematically model proteasome activity, cleavage preference variation and their modification by one of the regulatory mechanisms are reviewed here.
Topics: Animals; Humans; Hydrolysis; Models, Biological; Oligopeptides; Proteasome Endopeptidase Complex
PubMed: 24970232
DOI: 10.3390/biom4020585 -
Journal of Applied Biomaterials &... 2021Dentin hypersensitivity (DH) is a common oral disease with approximately 41.9% prevalence. Reconstruction of dental hard tissues is the preferred treatment for relieving...
OBJECTIVE
Dentin hypersensitivity (DH) is a common oral disease with approximately 41.9% prevalence. Reconstruction of dental hard tissues is the preferred treatment for relieving DH. Here, we applied biomineralization method using oligopeptide simulating cementum protein 1 (CEMP1) to regenerate hard tissues on demineralized dentin.
METHODS
The self-assembly and biomineralization property of the oligopeptide were detected by scanning electron microscopy (SEM), circular dichroism spectroscopy, and transmission electron microscopy. Oligopeptide's binding capacity to demineralized dentin was evaluated by SEM and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Remineralization was characterized using SEM, ATR-FTIR, X-ray diffraction, and nanoindentation. Oligopeptide's biocompatibility was evaluated using periodontal ligament cells.
RESULTS
Oligopeptides self-assembled into nano-matrix and templated mineral precursor formation within 24 h. Moreover, oligopeptide nano-matrix bound firmly on demineralized dentin and resisted water rinsing. Then, bound nano-matrix served as a template to initiate nucleation and transformation of hydroxyapatite on demineralized dentin. After 96 h, oligopeptide nano-matrix regenerated an enamel-like tissue layer with a thickness of 15.35 μm, and regenerated crystals occluded dentin tubules with a depth of 31.27 μm. Furthermore, the oligopeptide nano-matrix had good biocompatibility when co-cultured with periodontal ligament cells.
CONCLUSIONS
This biomimetic oligopeptide simulating CEMP1 effectively induced remineralization and reconstructed hard tissues on demineralized dentin, providing a potential biomaterial for DH treatment.
Topics: Biomimetics; Dental Enamel; Dentin; Dentin Sensitivity; Humans; Microscopy, Electron, Scanning; Oligopeptides; Proteins
PubMed: 33784188
DOI: 10.1177/22808000211005384 -
Experimental Dermatology Aug 2012Peptides are central to the regulation and modulation of the chemical reactions and biological responses that occur in nature. Many physiological processes are affected... (Review)
Review
Peptides are central to the regulation and modulation of the chemical reactions and biological responses that occur in nature. Many physiological processes are affected by the interactions of these peptides, including cell proliferation and migration, inflammation, melanogenesis, angiogenesis and innate immunity. Thus, biologically active peptides offer a great potential medically and therapeutically. Moreover, the ability to generate synthetic peptides with attention to specifically modulating their pharmacokinetics and properties for increased potency, delivery and stability has spurred much interest in this rapidly growing field of research. In this review, we focus on the therapeutic uses of bioactive peptides as antimicrobials and effectors of neurotransmitter release. We also highlight the advantages and challenges associated with this new technology and discuss methods for improving oligopeptide transdermal delivery.
Topics: Administration, Cutaneous; Anti-Infective Agents; Biological Products; Humans; Neurotransmitter Agents; Oligopeptides; Skin Diseases
PubMed: 22672721
DOI: 10.1111/j.1600-0625.2012.01527.x -
Nutrients Nov 2022Aging-related learning and memory decline are hallmarks of aging and pose a significant health burden. The effects of walnut oligopeptides (WOPs) on learning and memory...
Aging-related learning and memory decline are hallmarks of aging and pose a significant health burden. The effects of walnut oligopeptides (WOPs) on learning and memory were evaluated in this study. Sixty SAMP8 mice were randomly divided into four groups (15 mice/group), including one SAMP8 age-control group and three WOP-treated groups. SAMR1 mice ( = 15) that show a normal senescence rate were used as controls. The SAMP8 and SAMR1 controls were administered ordinary sterilized water, while the WOP-intervention groups were administered 110, 220, and 440 mg/kg·bw of WOPs in water, respectively. The whole intervention period was six months. The remaining 15 SAMP8 (4-month-old) mice were used as the young control group. The results showed that WOPs significantly improved the decline in aging-related learning/memory ability. WOPs significantly increased the expression of BDNF and PSD95 and decreased the level of APP and Aβ1-42 in the brain. The mechanism of action may be related to an increase in the activity of antioxidant enzymes (SOD and GSH-Px), a reduction in the expression of inflammatory factors (TNF-α and IL-1β) in the brain and a reduction in oxidative stress injury (MDA). Furthermore, the expression of AMPK, SIRT-1, and PGC-1α was upregulated and the mitochondrial DNA content was increased in brain. These results indicated that WOPs improved aging-related learning and memory impairment. WOP supplementation may be a potential and effective method for the elderly.
Topics: Animals; Mice; Aging; Juglans; Maze Learning; Memory Disorders; Oligopeptides; Water
PubMed: 36501089
DOI: 10.3390/nu14235059 -
Toxins Jun 2014Cyanobacterial oligopeptides comprise a wide range of bioactive and/or toxic compounds. While current research is strongly focused on exploring new oligopeptide variants... (Review)
Review
Cyanobacterial oligopeptides comprise a wide range of bioactive and/or toxic compounds. While current research is strongly focused on exploring new oligopeptide variants and their bioactive properties, the biological role of these compounds remains elusive. Oligopeptides production abilities show a remarkably patchy distribution among conspecific strains. This observation has prompted alternative approaches to unveil their adaptive value, based on the use of cellular oligopeptide compositions as biomarkers of intraspecific subpopulations or chemotypes in freshwater cyanobacteria. Studies addressing the diversity, distribution, and dynamics of chemotypes in natural systems have provided important insights into the structure and ecology of cyanobacterial populations and the adaptive value of oligopeptides. This review presents an overview of the fundamentals of this emerging approach and its most relevant findings, and discusses our current understanding of the role of oligopeptides in the ecology of cyanobacteria.
Topics: Adaptation, Biological; Bacterial Proteins; Bacterial Toxins; Bacterial Typing Techniques; Biodiversity; Biological Evolution; Biomarkers; Cyanobacteria; Fresh Water; Models, Biological; Molecular Structure; Oligopeptides; Peptides, Cyclic; Secondary Metabolism; Species Specificity; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 24960202
DOI: 10.3390/toxins6061929 -
Marine Drugs Feb 2023To investigate the effects of bonito oligopeptide SEP-3 on the repair of liver damage and regulation of liver biorhythm in sleep-deprived mice (SDM), C57BL/6 male mice...
To investigate the effects of bonito oligopeptide SEP-3 on the repair of liver damage and regulation of liver biorhythm in sleep-deprived mice (SDM), C57BL/6 male mice were subjected to sleep deprivation by modified multi-platform water environment method, and were given different doses of bonito oligopeptide SEP-3 in groups. To determine the liver organ index, liver tissue-related apoptotic protein levels, Wnt/β-Catenin pathway-related protein expression levels, serum alanine transaminase (ALT), glutamicum transaminase (AST), glucocorticoid (GC), and adrenocorticotropin (ACTH) content in each group of mice, four time points were selected to examine the mRNA expression levels of circadian clock-related genes in mouse liver tissue. The results showed that low, medium, and high doses of SEP-3 significantly increased SDM, ALT, and AST ( < 0.05), and medium and high doses of SEP-3 significantly reduced SDM liver index and GC and ACTH. As SEP-3 increased the apoptotic protein and Wnt/β-Catenin pathway, mRNA expression gradually tended to normal ( < 0.05). This suggests that sleep deprivation can cause excessive oxidative stress in mice, which can lead to liver damage. Additionally, oligopeptide SEP-3 achieves the repair of liver damage by inhibiting SDM hepatocyte apoptosis, activating liver Wnt/β-Catenin pathway, and promoting hepatocyte proliferation and migration, and suggests that oligopeptide SEP-3 is closely related to repair of liver damage by regulating the biological rhythm of SDM disorder.
Topics: Mice; Male; Animals; beta Catenin; Sleep Deprivation; Mice, Inbred C57BL; Liver; Apoptosis; Oxidative Stress; Oligopeptides; RNA, Messenger
PubMed: 36976188
DOI: 10.3390/md21030139 -
Viruses Oct 2013Phage display has become an established, widely used method for selection of peptides, antibodies or alternative scaffolds. The use of phage display for the selection of... (Review)
Review
Phage display has become an established, widely used method for selection of peptides, antibodies or alternative scaffolds. The use of phage display for the selection of antigens from genomic or cDNA libraries of pathogens which is an alternative to the classical way of identifying immunogenic proteins is not well-known. In recent years several new applications for oligopeptide phage display in disease related fields have been developed which has led to the identification of various new antigens. These novel identified immunogenic proteins provide new insights into host pathogen interactions and can be used for the development of new diagnostic tests and vaccines. In this review we focus on the M13 oligopeptide phage display system for pathogen research but will also give examples for lambda phage display and for applications in other disease related fields. In addition, a detailed technical work flow for the identification of immunogenic oligopeptides using the pHORF system is given. The described identification of immunogenic proteins of pathogens using oligopeptide phage display can be linked to antibody phage display resulting in a vaccine pipeline.
Topics: Antigens; Bacteriophage M13; Bacteriophage lambda; Cell Surface Display Techniques; Oligopeptides
PubMed: 24136040
DOI: 10.3390/v5102531 -
Methods in Molecular Biology (Clifton,... 2015Phage display enables the synthesis, selection, and screening of large, polypeptide libraries (>1 × 10(10) different members). Selections from such libraries can... (Review)
Review
Phage display enables the synthesis, selection, and screening of large, polypeptide libraries (>1 × 10(10) different members). Selections from such libraries can identify binding partners to essentially any desired target (Sarikaya et al., Annu Rev Mater Res 34:373-408, 2004; Deutscher, Chem Rev 110:3196-3211, 2010). Peptides with affinity or reactivity to small molecule probes are attractive for numerous uses including the targeted, site-specific labeling of proteins. Here, we describe selection and screening protocols for the identification of short peptides that can selectively bind to and/or react with small molecules.
Topics: Animals; Directed Molecular Evolution; Humans; Oligopeptides; Peptide Library
PubMed: 25616334
DOI: 10.1007/978-1-4939-2020-4_13