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Chimia 2013Structural biomaterials with their often extraordinary properties and versatile functions are typically constructed from very limited sets of building blocks and types... (Review)
Review
Structural biomaterials with their often extraordinary properties and versatile functions are typically constructed from very limited sets of building blocks and types of supramolecular interactions. In this review we discuss how, inspired by nature's design principles for protein-based materials, oligopeptide-modified polymers can be used as a versatile toolbox to program nanostructure and hierarchical structure formation in synthetic materials.
Topics: Amyloid beta-Peptides; Nanowires; Nature; Oligopeptides
PubMed: 24388229
DOI: 10.2533/chimia.2013.782 -
Nucleic Acids Research Jan 2006Natural oligopeptides may regulate nearly all vital processes. To date, the chemical structures of nearly 6000 oligopeptides have been identified from >1000 organisms...
Natural oligopeptides may regulate nearly all vital processes. To date, the chemical structures of nearly 6000 oligopeptides have been identified from >1000 organisms representing all the biological kingdoms. We have compiled the known physical, chemical and biological properties of these oligopeptides--whether synthesized on ribosomes or by non-ribosomal enzymes--and have constructed an internet-accessible database, EROP-Moscow (Endogenous Regulatory OligoPeptides), which resides at http://erop.inbi.ras.ru. This database enables users to perform rapid searches via many key features of the oligopeptides, and to carry out statistical analysis of all the available information. The database lists only those oligopeptides whose chemical structures have been completely determined (directly or by translation from nucleotide sequences). It provides extensive links with the Swiss-Prot-TrEMBL peptide-protein database, as well as with the PubMed biomedical bibliographic database. EROP-Moscow also contains data on many oligopeptides that are absent from other convenient databases, and is designed for extended use in classifying new natural oligopeptides and for production of novel peptide pharmaceuticals.
Topics: Anti-Infective Agents; Databases, Protein; Internet; Moscow; Neuropeptides; Oligopeptides; Peptide Hormones; Toxins, Biological; User-Computer Interface
PubMed: 16381860
DOI: 10.1093/nar/gkj008 -
Asia Pacific Journal of Clinical... 2017Oligosaccharide or oligopeptide supplementation may have a significant impact on endurance performance. This study evaluated the effects of adding maltooligosaccharides...
BACKGROUND AND OBJECTIVES
Oligosaccharide or oligopeptide supplementation may have a significant impact on endurance performance. This study evaluated the effects of adding maltooligosaccharides (MO) or soy oligopeptides (SO) to compressed food (CF) on the physical response of soldiers to daily military training.
METHODS AND STUDY DESIGN
Twelve soldiers were randomized to four diet groups: regular meals, CF, CFMO, and CFSO (crossover design). They participated in exercise tests including 90 minutes running at 55-65% VO2max and exhaustive running. Heart rates, rating of perceived exertion (RPE), and blood and urine samples were collected during exercise and recovery.
RESULTS
The recovery heart rates were significantly lower with the CFMO diet compared with the other diets. Compared with all other diets, blood glucose levels were higher, post-exercise blood lactate levels were lower, and lactate clearance during recovery was higher with the CFMO diet, followed by the CFSO diet. Post-exercise levels of erythrocytes and hematocrit were significantly higher with the CFSO diet. Post-exercise urine specific gravity was lower with the CFMO diet and urine pH was decreased with the CFSO diet. Blood urea nitrogen (BUN) and uric acid (UA) were significantly higher with the CFSO diet than with the other diets. There was no significant difference in skeletal and cardiac muscle injury indices and RPE among diets.
CONCLUSIONS
CFMO led to better heart rate recovery, improved and maintained blood glucose and increased removal of blood lactate. CFSO accelerated removal of blood lactate during recovery, maintained oxygen supply, and increased fluid retention.
Topics: Blood Glucose; Cross-Over Studies; Food Analysis; Food Handling; Heart Rate; Humans; Lactates; Military Personnel; Oligopeptides; Physical Endurance
PubMed: 28917232
DOI: 10.6133/apjcn.122016.06 -
Microbiology Spectrum Aug 2022The chloroquine resistance transporter, PfCRT, is an essential factor during intraerythrocytic development of the human malaria parasite Plasmodium falciparum. PfCRT...
The chloroquine resistance transporter, PfCRT, is an essential factor during intraerythrocytic development of the human malaria parasite Plasmodium falciparum. PfCRT resides at the digestive vacuole of the parasite, where hemoglobin taken up by the parasite from its host cell is degraded. PfCRT can acquire several mutations that render PfCRT a drug transporting system expelling compounds targeting hemoglobin degradation from the digestive vacuole. The non-drug related function of PfCRT is less clear, although a recent study has suggested a role in oligopeptide transport based on studies conducted in a heterologous expression system. The uncertainty about the natural function of PfCRT is partly due to a lack of a null mutant and a dearth of functional assays in the parasite. Here, we report on the generation of a conditional PfCRT knock-down mutant in P. falciparum. The mutant accumulated oligopeptides 2 to at least 8 residues in length under knock-down conditions, as shown by comparative global metabolomics. The accumulated oligopeptides were structurally diverse, had an isoelectric point between 4.0 and 5.4 and were electrically neutral or carried a single charge at the digestive vacuolar pH of 5.2. Fluorescently labeled dipeptides and live cell imaging identified the digestive vacuole as the compartment where oligopeptides accumulated. Our findings suggest a function of PfCRT in oligopeptide transport across the digestive vacuolar membrane in P. falciparum and associated with it a role in nutrient acquisition and the maintenance of the colloid osmotic balance. The chloroquine resistance transporter, PfCRT, is important for the survival of the human malaria parasite Plasmodium falciparum. It increases the tolerance to many antimalarial drugs, and it is essential for the development of the parasite within red blood cells. While we understand the role of PfCRT in drug resistance in ever increasing detail, the non-drug resistance functions are still debated. Identifying the natural substrate of PfCRT has been hampered by a paucity of functional assays to test putative substrates in the parasite system and the absence of a parasite mutant deficient for the PfCRT encoding gene. By generating a conditional PfCRT knock-down mutant, together with comparative metabolomics and uptake studies using fluorescently labeled oligopeptides, we could show that PfCRT is an oligopeptide transporter. The oligopeptides were structurally diverse and were electrically neutral or carried a single charge. Our data support a function of PfCRT in oligopeptide transport.
Topics: Antimalarials; Chloroquine; Humans; Malaria; Malaria, Falciparum; Membrane Transport Proteins; Oligopeptides; Plasmodium falciparum; Protozoan Proteins
PubMed: 35867395
DOI: 10.1128/spectrum.01101-22 -
Infection and Immunity Oct 2014The anaerobic gastrointestinal pathogen Clostridium difficile must form a metabolically dormant spore to survive in oxygenic environments and be transmitted from host to...
The anaerobic gastrointestinal pathogen Clostridium difficile must form a metabolically dormant spore to survive in oxygenic environments and be transmitted from host to host. The regulatory factors by which C. difficile initiates and controls the early stages of sporulation in C. difficile are not highly conserved in other Clostridium or Bacillus species. Here, we investigated the role of two conserved oligopeptide permeases, Opp and App, in the regulation of sporulation in C. difficile. These permeases are known to positively affect sporulation in Bacillus species through the import of sporulation-specific quorum-sensing peptides. In contrast to other spore-forming bacteria, we discovered that inactivating these permeases in C. difficile resulted in the earlier expression of early sporulation genes and increased sporulation in vitro. Furthermore, disruption of opp and app resulted in greater virulence and increased the amounts of spores recovered from feces in the hamster model of C. difficile infection. Our data suggest that Opp and App indirectly inhibit sporulation, likely through the activities of the transcriptional regulator SinR and its inhibitor, SinI. Taken together, these results indicate that the Opp and App transporters serve a different function in controlling sporulation and virulence in C. difficile than in Bacillus subtilis and suggest that nutrient availability plays a significant role in pathogenesis and sporulation in vivo. This study suggests a link between the nutritional status of the environment and sporulation initiation in C. difficile.
Topics: Animals; Bacterial Load; Clostridioides difficile; Clostridium Infections; Cricetinae; Disease Models, Animal; Feces; Female; Gene Expression Regulation, Bacterial; Gene Knockout Techniques; Membrane Transport Proteins; Mesocricetus; Oligopeptides; Spores, Bacterial; Virulence
PubMed: 25069979
DOI: 10.1128/IAI.02323-14 -
Molecules (Basel, Switzerland) Mar 2020In clinical culture media inoculated with patient samples, selective inhibition of commensal bacteria is essential for accurate diagnosis and effective treatment, as...
In clinical culture media inoculated with patient samples, selective inhibition of commensal bacteria is essential for accurate diagnosis and effective treatment, as they can mask the presence of pathogenic bacteria. The alanine analogue, 1-aminoethyltetrazole was investigated as a potential alanine racemase inhibitor. For effective uptake and enhanced and selective antibacterial activity, a library of C-terminal 1-aminoethyltetrazole containing di- and oligopeptides were synthesized by solid phase peptide coupling techniques. The investigation of the antimicrobial activity of the synthesised compounds identified several clinically applicable selective inhibitors. These enabled differentiation between the closely related bacteria, and , which can be difficult to discriminate between in a clinical setting. In addition, differentiation between enterococci and other Gram-positive cocci was also seen.
Topics: Alanine Racemase; Enzyme Inhibitors; Microbial Sensitivity Tests; Oligopeptides; Solid-Phase Synthesis Techniques; Tetrazoles
PubMed: 32183087
DOI: 10.3390/molecules25061315 -
Japanese Journal of Pharmacology Jul 2002Endomorphin-1 (Tyr-Pro-Trp-Phe-NH2, EM-1) and endomorphin-2 (Tyr-Pro-Phe-Phe-NH2, EM-2) have the highest affinity and selectivity for the mu-opioid receptor (MOP-R) of... (Review)
Review
Endomorphin-1 (Tyr-Pro-Trp-Phe-NH2, EM-1) and endomorphin-2 (Tyr-Pro-Phe-Phe-NH2, EM-2) have the highest affinity and selectivity for the mu-opioid receptor (MOP-R) of all known mammalian opioids. They were isolated from bovine and human brain, and are structurally distinct from the other endogenous opioids. Both EM-1 and EM-2 have potent antinociceptive activity in a variety of animal models of acute, neuropathic and allodynic pain. They regulate cellular signaling processes in a manner consistent with MOP-R-mediated effects. The EMs are implicated in the natural modulation of pain by extensive data localizing EM-like immunoreactivity (EM-LI) near MOP-Rs in several regions of the nervous system known to regulate pain. These include the primary afferents and their terminals in the spinal cord dorsal horn, where EM-2 is well-positioned to modulate pain in its earliest stages of perception. In a nerve-injury model of chronic pain, a loss of spinal EM2-LI occurs concomitant with the onset of chronic pain. The distribution of the EMs in other areas of the nervous system is consistent with a role in the modulation of diverse functions, including autonomic, neuroendocrine and reward functions as well as modulation of responses to pain and stress. Unlike several other mu opioids, the threshold dose of EM-1 for analgesia is well below that for respiratory depression. In addition, rewarding effects of EM-1 can be separated from analgesic effects. These results indicate a favorable therapeutic profile of EM-1 relative to other mu opioids. Thus, the pharmacology and distribution of EMs provide new avenues both for therapeutic development and for understanding the neurobiology of opioids.
Topics: Animals; Central Nervous System; Humans; Oligopeptides; Pain
PubMed: 12184722
DOI: 10.1254/jjp.89.203 -
FEMS Microbiology Reviews Jul 2006Cyanobacterial secondary metabolites have attracted increasing scientific interest due to bioactivity of many compounds in various test systems. Among the known... (Review)
Review
Cyanobacterial secondary metabolites have attracted increasing scientific interest due to bioactivity of many compounds in various test systems. Among the known structures, oligopeptides are often found with many congeners sharing conserved substructures, while being highly variable in others. A major part of known oligopeptides are of non-ribosomal origin and can be grouped into classes with conserved structural properties. Thus, the overall structural diversity of cyanobacterial oligopeptides only seemingly suggests an equally high diversity of biosynthetic pathways and respective genes. For each class of peptides, some of which have been found in all major branches of the cyanobacterial evolutionary tree, homologous synthetases and genes can be inferred. This implies that non-ribosomal peptide synthetase genes are a very ancient part of the cyanobacterial genome and presumably have evolved by recombination and duplication events to reach the present structural diversity of cyanobacterial oligopeptides. In addition, peptide synthetases would appear to be an essential part of the cyanobacterial evolution and physiology. The present review presents an overview of the biosynthesis of cyanobacterial peptides and corresponding gene clusters, the structural diversity of structural types and structural variations within peptide classes, and implications for the evolution and plasticity of biosynthetic genes and the potential function of cyanobacterial peptides.
Topics: Cyanobacteria; Evolution, Molecular; Oligopeptides; Peptide Biosynthesis, Nucleic Acid-Independent; Peptide Synthases; Protein Biosynthesis; Structure-Activity Relationship
PubMed: 16774586
DOI: 10.1111/j.1574-6976.2006.00022.x -
The International Journal of... Feb 1996Experimental data reveal that most, if not all, major events in the metagenetic life-cycle of Cassiopea spp. at these checkpoints depend on the interaction with specific... (Review)
Review
Experimental data reveal that most, if not all, major events in the metagenetic life-cycle of Cassiopea spp. at these checkpoints depend on the interaction with specific biotic and physical cues. For medusa formation within a permissive temperature range by monodisk strobilation of the polyp, the presence of endosymbiotic dinoflagellates is indispensable. The priming effect of the algal symbionts is not primarily coupled with photosynthetic activity, but was found to be enhanced in the light. Budding of larva-like propagules by the polyp, however, is independent from such zooxanthellae. On the other hand the budding rate is influenced by various rearing conditions. Exogenous chemical cues control settlement and metamorphosis into scyphopolyps of both sexually produced planula larvae and asexual propagules. In laboratory experiments two classes of metamorphosis inducing compounds have been detected: a family of oligopeptides, featuring a proline-residue next to the carboxyterminal amino acid, and several phorbol esters. Using the peptide 14C-DNS-GPGGPA, induction of metamorphosis has been shown to be receptor-mediated. Furthermore, activation of protein kinase C, a key enzyme within the inositolphospholipid-signalling pathway appears to be involved in initiating metamorphosis. In mangrove habitats of Cassiopea spp. planula larvae specifically settle and metamorphose on submerged, deteriorating mangrove leaves from which biologically active fractions have been isolated. The chemical characterisation and comparison of these compounds from the natural environment with the properties and mode of action of oligopeptide inducers is in progress.
Topics: Amino Acid Sequence; Animals; Larva; Metamorphosis, Biological; Oligopeptides; Phorbol Esters; Protein Kinase C; Receptors, Cell Surface; Scyphozoa
PubMed: 8735945
DOI: No ID Found -
Toxins Apr 2016Despite their cosmopolitan distribution, knowledge on cyanobacteria in the family Coelosphaeriaceae is limited. In this study, a single species culture of a...
Despite their cosmopolitan distribution, knowledge on cyanobacteria in the family Coelosphaeriaceae is limited. In this study, a single species culture of a coelosphaeran cyanobacterium isolated from a brackish rock pool in the Baltic Sea was established. The strain was characterized by morphological features, partial 16S rRNA sequence and nonribosomal oligopeptide profile. The bioactivity of fractionated extracts against several serine proteases, as well as protein-serine/threonine phosphatases was studied. Phylogenetic analyses of the strain suggested a close relationship with Snowella litoralis, but its morphology resembled Woronichinia compacta. The controversial morphologic and phylogenetic results demonstrated remaining uncertainties regarding species division in this cyanobacteria family. Chemical analyses of the strain indicated production of nonribosomal oligopeptides. In fractionated extracts, masses and ion fragmentation spectra of seven possible anabaenopeptins were identified. Additionally, fragmentation spectra of cyanopeptolin-like peptides were collected in several of the fractions. The nonribosomal oligopeptide profile adds another potential identification criterion in future inter- and intraspecies comparisons of coelosphaeran cyanobacteria. The fractionated extracts showed significant activity against carboxypeptidase A and trypsin. Inhibition of these important metabolic enzymes might have impacts at the ecosystem level in aquatic habitats with high cyanobacteria densities.
Topics: Carboxypeptidases A; Chymotrypsin; Cyanobacteria; DNA, Bacterial; Oligopeptides; Pancreatic Elastase; Phylogeny; Protein Phosphatase 1; Protein Phosphatase 2; RNA, Ribosomal, 16S; Saline Waters; Thrombin
PubMed: 27077885
DOI: 10.3390/toxins8040108