Everything below concerns TP-7. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-10-14. Where a claim depends on a specific study, the study is described rather than over-claimed.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Once dissolved, the peptide is markedly less stable than the dry powder. Aqueous solutions are subject to backbone hydrolysis and to microbial growth when they are handled without sterile technique. Buffered solutions near neutral pH are common for short-term laboratory work, while acidic conditions are sometimes used to improve solubility. Analytical laboratories generally prepare working solutions fresh rather than storing them, and a residual water film left in a reopened vial can seed degradation even when the container appears dry.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue with a C-terminal Pro-Gly-Pro tail |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Abbreviated TKPRPGP in most catalogues |
| Molecular mass | About 752 Da | Value for the free peptide |
| Solubility | Freely soluble in water | Aqueous solutions are kept cold and used promptly |
| Typical storage | -20 °C, dry, protected from light | Applies to the lyophilised powder before reconstitution |
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
The compound was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences during the 1980s and 1990s. The stated design goal was to retain the immunomodulatory and central nervous system activity attributed to tuftsin while improving resistance to enzymatic breakdown. Adding a proline-rich tail to the short parent peptide was a deliberate strategy, because proline residues restrict the conformations available to many peptidases. The same laboratory produced Semax, an ACTH fragment analog, and both compounds were developed in parallel as short, enzymatically stabilized peptides intended for intranasal use.
Selank is not a naturally occurring peptide and has no known endogenous counterpart in human physiology. Russian-language sources frequently call it TP-7, while English-language sources use the name Selank almost exclusively. Database indexing is uneven, partly because early reports appeared in regional journals that are not widely cataloged. Some summaries describe the material as a tuftsin analog and others as a synthetic heptapeptide; the labels overlap rather than conflict. Citing the primary sequence resolves ambiguity more reliably than the research or trade name alone.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
=== Reducing risk of cancer === According to the American Cancer Society, "There is growing evidence that eating traditional soy foods such as tofu may lower the risk of cancers of the breast, prostate, or endometrium (lining of the uterus), and there is some evidence it may lower the risk of certain other cancers." There is insufficient research to indicate whether taking soy dietary supplements (e.g., as a pill or capsule) has any effect on health or cancer risk. As of 2018, rigorous dietary clinical research in people with cancer has proved inconclusive.
autoignition temperature Also kindling point. The lowest temperature at which a given substance will spontaneously ignite in a normal atmosphere without an external source of ignition such as a flame or spark, i.e. when the ambient temperature is sufficiently high to provide the activation energy needed for combustion. Substances which spontaneously ignite at naturally occurring temperatures are termed pyrophoric. Compare ignition temperature.
==== Medallists ==== The Reverend Canon William Matthew Adair. Rector, St Columba's Parish, Portadown. For services to the Church of Ireland and to the community in Portadown, County Armagh. Sean Adcock. Master Craftsman. For services to Dry Stone Walling. Rasheed Alawiye. Detective Inspector, Metropolitan Police Service. For services to Policing, and to Diversity and Inclusion. Christopher Allen. For services to the community in Chesterfield, Derbyshire. Dr. Jahangir Alom. Doctor and Campaigner, NHS. For services to Tackling Health Inequalities, particularly during Covid-19. Carl Peter Anglim. Lately Chair, Oxfordshire Youth. For services to Young People. Margaret Helen Archibald. Founder, Everyone Matters. For services to Music. Reverend Margaretha Catharina Maria Armitstead. For services to the community in Littlemore, Oxfordshire. Keith Morton Armour. Fundraiser, Children's Hospices Across Scotland. For Charitable Services. Olive Arnold. For services to the community in Bronington, Shropshire. Robert Arnott. For services to the community in Coventry. Waqas Arshad. Chair, Bradley Big Local. For services to Families with Mental Health Issues in Lancashire. Saeqa Ashraf. For services to Law Enforcement. Reverend Christine Joyce Aspinall. For services to the community in Old Trafford, Greater Manchester. Moses Olawole Ayoola. Director, Estates and Facilities, Lewisham and Greenwich NHS Trust and Guy's and St Thomas' NHS Foundation Trust. For services to Leadership in the NHS. Enid Bacon. Founder, Beck Row Preschool, Bury St Edmunds. For services to Early Education.
== Techniques for data analysis == Global proteome profiling is the direct representation of the protein set in an organism, organ, tissues, or an organelle. Among the primary goals of proteomic analysis is to compare and determine the relative quantities of proteins under a defined set of conditions. Over the last 4 decades, two-dimensional gel electrophoresis has gained popularity because it successfully helped differential proteomics provide visual proof of changes in protein abundance that cannot be predicted from genome analysis. Each protein spot on a 2-DE gel can be analyzed based on its abundance, location, or even presence and absence. This flexible gel-based method combines and makes use of the best principle for separation of protein complexes based on their charge and mass, visual mapping coupled with successful mass spectrometric identification of individual proteins. Latest developments in proteomics have paved the way for the discovery of techniques such as colocalization analysis (COLA), which detects protein–protein co-localizations at a global scale. This helps map interactome dynamics under various conditions, making it possible to understand protein interactions and functions. Proteomic profiling relates to each individual's physiological changes by the monitoring of protein expression variations according to factors such as aging, exercise, and environmental conditions. For example, in aging muscle, proteomic analysis showed changes in protein isoforms and altered metabolic pathways that indicate adaptations in muscle functions and energy metabolism.
Sources: en.wikipedia.org
== Metabolism == Lactiplantibacillus plantarum are homofermentative, aerotolerant Gram-positive bacteria that grow at 15 °C (59 °F), but not at 45 °C (113 °F), and produce both enantiomers of lactic acid (D and L). Many lactobacilli including L. plantarum are unusual in that they can respire oxygen and express cytochromes if heme and menaquinone are present in the growth medium. In the absence of heme and menaquinone, oxygen is consumed by NADH-peroxidase with hydrogen peroxide as intermediate and water as end product. The peroxide, it is presumed, acts as a weapon to exclude competing bacteria from the food source. In place of the protective enzyme superoxide dismutase present in almost all other oxygen-tolerant cells, this organism accumulates millimolar quantities of manganese polyphosphate. Manganese is also used by L. plantarum in a pseudo-catalase to lower reactive oxygen levels. Because the chemistry by which manganese complexes protect the cells from oxygen damage is subverted by iron, these cells contain virtually no iron atoms; in contrast, a cell of Escherichia coli of comparable volume contains over one-million iron atoms. Because of this, L. plantarum cannot be used to create active enzymes that require a heme complex, such as true catalases. L. plantarum can also reduce insoluble terminal electron acceptors, such as iron oxides or solid electrodes through extracellular electron transfer when riboflavin and quinone (such as 1 4-dihydroxy-2-naphthoic acid, DHNA) are present. L.
=== Cell culture === One of the key advantages of droplet-based microfluidics is the ability to use droplets as incubators for single cells. In addition, droplets can be applied for studies on embryogenesis of animals and plants. Devices capable of generating thousands of droplets per second open new ways to characterize cell populations, not only based on a specific marker measured at a specific time point but also based on cells' kinetic behavior such as protein secretion, enzyme activity or proliferation. Recently, a method was found to generate a stationary array of microscopic droplets for single-cell incubation that does not require the use of a surfactant.
=== Indoor air-quality measurements === Measurement of VOCs from the indoor air is done with sorption tubes e. g. Tenax (for VOCs and SVOCs) or DNPH-cartridges (for carbonyl-compounds) or air detector. The VOCs adsorb on these materials and are afterwards desorbed either thermally (Tenax) or by elution (DNPH) and then analyzed by GC–MS/FID or HPLC. Reference gas mixtures are required for quality control of these VOC measurements. Furthermore, VOC emitting products used indoors, e.g. building products and furniture, are investigated in emission test chambers under controlled climatic conditions. For quality control of these measurements round robin tests are carried out, therefore reproducibly emitting reference materials are ideally required. Other methods have used proprietary Silcosteel-coated canisters with constant flow inlets to collect samples over several days. These methods are not limited by the adsorbing properties of materials like Tenax.
Producing better protein: the evolution of T7 bacteriophages on a non-evolving E. coli strain that encoded 3-iodotyrosine on the amber codon, resulted in a population fitter than wild-type thanks to the presence of iodotyrosine in its proteome Probing protein localization and protein-protein interaction in bacteria.
The draining of the Qurna Marshes was an irrigation project in Iraq during and immediately after the war, to drain a large area of marshes in the Tigris–Euphrates river system. Formerly covering an area of around 3,000 km2 (1,200 sq mi), the large complex of wetlands were nearly emptied of water, and the local Shi'ite population relocated, following the war and 1991 uprisings. By 2000, the United Nations Environment Programme estimated that 90% of the marshlands had disappeared, causing desertification of over 7,500 square miles (19,000 km2). The draining occurred in Iraq and to a smaller degree in Iran between the 1950s and 1990s to clear large areas of the marshes. Formerly covering an area of around 20,000 km2 (7,700 sq mi), the large complex of wetlands was 90% drained before the 2003 Invasion of Iraq. The marshes are typically divided into three main sub-marshes, the Hawizeh, Central, and Hammar Marshes and all three were drained at different times for different reasons. Initial draining of the Central Marshes was intended to reclaim land for agriculture but later all three marshes would become a tool of war and revenge. Many international organizations such as the UN Human Rights Commission, the Islamic Supreme Council of Iraq, the Wetlands International, and Middle East Watch have described the project as a political attempt to force the Marsh Arabs out of the area through water diversion tactics.
Sources: en.wikipedia.org
Although it is not entirely clear which gene causes the resistance phenotype, there is strong evidence supporting the correlation between a mutation in the membrane transporter ABCC2 and Bt resistance. Other studies with greenhouse-evolved population of Bt resistant cabbage looper demonstrate that the downregulation of the aminopeptidase N, APN1, results in its resistance.
All of these instruments provide a high mass accuracy (<2–3 ppm with external calibrant and <1–2 ppm with internal), a high resolving power (up to 240,000 at m/z 400), a high dynamic range and high sensitivity.
Narrated by Eva Pope, produced by David Frank, directed by Paul Sapin; made by RDF Media and the Discovery Channel 15 September The Secret Life of the Dog, with David Paxton of the University of Papua New Guinea; Jonica Newby wrote The Pact for Survival; 75% of all dogs came from one female dog 100,000 years ago, from mitochondrial genetic evidence; British zoologist John Bradshaw; anthropologist Colin Groves of Australian National University; the domestication of dogs has been modelled by Russian zoologist Lyudmila Trut and experiments from 1952 on the domesticated silver fox, whereby only individual silver foxes that didn't bite humans could breed, at the Institute of Cytology and Genetics in Novosibirsk - by 1972, silver foxes from the silver fox Laska had become so suddenly similar to dogs, in their temperament, and would respond to their name being called; Russian zoologist Larissa Kolesnikova.
== History == Phytochelatin was first discovered in 1981 in fission yeast, and was named cadystin. It was then found in higher plants in 1985 and was named phytochelatin. In 1989 the biosynthetic enzyme, phytochelatin synthase, was discovered.
Sources: en.wikipedia.org
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.
Tuftsin is a natural tetrapeptide derived from the Fc portion of immunoglobulin G. Selank retains that tetrapeptide at its N-terminus and adds three residues to improve resistance to enzymatic breakdown. The relationship is structural, and the two molecules are not interchangeable in experimental work.
It holds a product registration in Russia for intranasal use as an anxiolytic. Registrations of that kind are not automatically accepted by regulators elsewhere. In most other countries it is treated as an unapproved substance or a research material.
Sealed, desiccated storage at -20 °C or colder is the standard recommendation for research-grade material. Vials should reach room temperature before they are opened, which limits condensation. Repeated temperature cycling is discouraged.