Compuestos y reactivos bioquímicos

<p>IRF3 antibody was raised in mouse using recombinant Interferon Regulatory Factor 3</p>

<p>Isotocin is a nonapeptide of the arginine vasopressin-oxytocin family produced exclusively in the preoptic area (POA) of teleosts. As a homologue of mammalian oxytocin, studying fish nonapeptides has shown that Isotocin mediates social and reproductive behaviour in fishes. Functional isotocin is stored in granules at the axon terminal with a carrier peptide, neurophysin. Stimuli leads to isotocin dissociation, to be released into the bloodstream or to cross over into the brain. It binds to G-protein coupled receptors (GPCRs), which subtype isotocin binds to defines the following physiological action. It, like other nonapeptides, is a neuromodulator in the CNS, but when distributed by the bloodstream, it acts as a peripheral hormone, such as regulating osmoregulation. Isotocin levels are sex-dependent and linked to the reproductive cycle.HPLC is a sensitive method to detect bioavailable isotocin and other nonapeptides. Measurement of mRNA levels of isotocin has been important to demonstrate the cyclical changes to regulate the endocrine calendar and diurnal rhythm. The level of isotocin is also considered a biomarker for aggression in behavioural indicators of fish welfare studies.</p>

<p>Angiotensin II (Ang-II) is a key signalling peptide of the renin angiotensin system (RAS) which is involved in regulating blood pressure, cardiovascular function and energy balance. RAS activity is elevated in obesity and is widely studied in relation to lifestyle-related diseases.Ang-II is produced from angiotensinogen (AGT) via the intermediate angiotensin I (Ang-I). AGT is cleaved by the aspartyl-protease, renin, to produce Ang-I, which is then cleaved by the dicarboxyl-peptidase angiotensin converting enzyme (ACE). ACE removes a histidine and a leucine from the C-terminus of Ang-I to form Ang-II.Ang-II exerts its affect by binding to the G-protein-coupled receptors- Ang II type 1 (AT1) and Ang II type 2 (AT2) receptors. Ang-II plays central roles in glucose metabolism and blood pressure. Increased levels of Ang-II have also been associated with Alzheimer's disease, and certain cancers including oesophageal squamous cell carcinoma (ESCC), brain cancers and breast cancers. The effects of Ang-II appear to be supressed by another branch of the RAS- the ACE2/Ang-(1-7)/Mas pathway.</p>

<p>Mouse monoclonal CSPS antibody</p>

<p>PFR-[AMC]</p>

<p>Peptide derived from the ubiquitin-activating enzyme 3 (UBA3), the catalytic subunit of the NEDD8-activating enzyme (NAE).</p>

<p>Portion of Influenza NP</p>

<p>YSA binds to the extracellular domain of ephrin type-A receptor 2 (EphA2) with high affinity and selectivity. YSA binding activates EphA2 and its tumour suppressing downstream signalling pathways (including inhibition of the PI3K/Akt and ERK pathways), and promotes receptor internalisation.EphA2 is highly expressed in many types of solid tumour, and the level of EphA2 expression is positively correlated with malignancy and poor prognosis in some cancer types.YSA has been shown to be an effective targeting peptide of chemotherapeutic drugs to EphA2 expressing tumours. YSA-drug conjugates are able to selectively target EphA2 expressing tumours, both activating tumour supressing downstream signalling pathways, and becoming effectively internalised by cancer cells to further increase the potency of the chemotherapeutic drug. YSA-drug conjugates have been shown to be dramatically more effective at inhibiting tumour growth than chemotherapy alone. Selective tumour targeting with YSA could also reduce the systemic toxicity caused by nonselective and highly toxic chemotherapy agents, and thus reduce adverse side effects of chemotherapy.</p>

<p>This peptide constitutes the acetylated N-terminal region of murine myelin basic protein (MBP) and displays high affinity for major histocompatibility complexes (MHC). This high MHC affinity is due to substitution of the native lysine at position 4 for a tyrosine. Substitution increases the MHC binding affinity of the peptide by around 1 million fold, therefore creating a superagonist ligand. MBP is an integral component of myelin found in the central nervous system (CNS) vital for the development and stability of the myelin sheath where it plays a role in membrane adhesion. MBP may be targeted by auto-antibodies in diseases such as multiple sclerosis. The low affinity of the native lysine containing MBP 1-9 peptide for MCH class II may result in MBP auto-reactive T cells escaping central-tolerance where self reactive T cells are usually eliminated. MBPs constitute an extraordinarily varied collection of splice isoforms which show a myriad of post-translational modifications.</p>

<p>Ovalbumin (OVA) is the primary protein in egg-white, and is involved in initiating food allergies and asthma. It is a highly immunogenic protein and can be used for peptide conjugation in the development of antibodies.OVA (323-339) is a class I (Kb)-restricted peptide epitope of OVA. The ovalbumin fragment is presented by the class I MHC molecule, H-2Kb.</p>

<p>Ganglioside GM1-binding peptides p3.</p>

<p>The SARS-CoV-2 spike protein is present on the outside of the virus particles and can bind to angiotensin-converting enzyme II (ACE2) present on the host cells. The C-terminal receptor binding domain (RBD) of the spike protein binds to the N-terminal peptidase M2 domain of ACE2. This receptor binding results in the internalisation of the virus-receptor complex and is, therefore the mechanism of entry of SARS-CoV-2 into host cells.The spike protein residues NLNESLIDL (1192-1200) from SARS-CoV-2 have been identified as a T-cell epitope with a predicted HLA restriction. Immune targeting of confirmed epitopes may potentially offer protection against SARS-CoV-2 and help the development of vaccines for long-lasting immunity.</p>

<p>The SARS-CoV-2 non-structural protein 13 (NSP13) has been identified as a target for anti-viral therapeutics due to its highly conserved sequence and is essential for viral replication.  NSP13 is part of the helicase superfamily 1B. As an NTPase and RNA helicase, NSP13 binds to RNA-dependent RNA polymerase and acts in concert with the replication-transcription complex to stimulate backtracking and further activate NSP13 helicase activity. These factors make NSP13 a good target for developing new antiviral drugs. In addition, the identification of epitopes within the NSP13 sequence can help design more effective SARS-CoV-2 vaccines.Models have predicted epitopes exhibiting antigenicity, stability and interactions with MHC class-I and class-II molecules. NSP13 (321-335) is an epitope candidate with various HLA restrictions. This epitope can be used to better vaccine design for more durable CD4+ and CD8+ T cell responses for long-lasting immunity.</p>

<p>Fibrinogen antibody was raised in mouse using fibrin degradation products as the immunogen.</p>

<p>Amino acids 45-73, derived from the exon 2/insert 1 domain, of tubulin-associated unit (tau). Tau is a phosphoprotein protein involved in microtubule (MT) assembly and stability as well as brain development. Tau is phosphorylated at multiple sites by several protein kinases, including cyclic-AMP-dependent protein kinases and casein kinase type-1. Tau phosphorylation causes tau to change shape negatively regulating its ability to stimulate MT assembly. Tau is also glycosylated, and O-glycosylation may have a role in its subcellular localisation and degradation.Malfunctioning tau protein contributes to the structural core of the paired helical filaments (PHFs), which make up neurofibrillary tangles (NFTs). NFTs are often observed in neurodegenerative disorders, such as Alzheimer disease and other tauopathies. Tau is expressed from a single gene and is alternatively spliced to yield six different isoforms in the adult central nervous system (CNS).</p>

<p>SARS-inhibitor 4</p>

<p>Ovalbumin (OVA) is the primary protein in egg-white, and is involved in initiating food allergies and asthma. It is a highly immunogenic protein and can be used for peptide conjugation in the development of antibodies.Biotin-OVA (323-339) is a biotin labelled class I (Kb)-restricted peptide epitope of OVA. The ovalbumin fragment is presented by the class I MHC molecule, H-2Kb.</p>

<p>Fz7-21 is a potent and selective peptide antagonist of Frizzled 7 (FZD 7) receptor which selectively binds to FZD7 cysteine rich domain (CRD) subclass at the cysteine rich region proximal to the lipid-binding groove. Binding alters the conformation of the CRD and the architecture of its lipid-binding groove and impairs Wnt/β-catenin signalling. Peptide Fz7-21 also shows cross-species binding to both the human and mouse FZD7 CRD.The FZD7 receptor is enriched in intestinal stem cells which express the LGR5 receptor and plays a critical role in the cells self-renewal. FZD7 is essential for maintaining human embryonic stem cells in their undifferentiated state and is therefore an attractive pharmacological target for diseases associated with stem cell dysfunction and cancer biology.FZD7 is also upregulated in subsets of colon, pancreatic and gastric tumours, therefore Fz7-21 serves as a pharmacological probe to explore further the function of FZD7 in stem cell and cancer biology.Peptide is labelled with an N-terminal 5-carboxyfluorescein (5-FAM), a widely used green fluorescent tag.</p>

<p>(Arg)9 is a cationic cell-penetrating peptide (CPP)consisting of 9 arginines. Arginine rich CPPs enter cells in a passive manner through membrane multilamellarity and fusion. Evidently as a CPP, (Arg)9 can function to deliver specific molecules to target cells and can be used for drug delivery purposes.</p>

<p>Metapneumovirus antibody was raised in mouse using matrix protein of human metapneumovirus as the immunogen.</p>

<p>Angiotensin I-converting enzyme (ACE) plays a critical role in blood pressure regulation. There is a rise in conditions linked to hypertension such as heart attacks, strokes, and dementia. This has led to search for novel inhibitors of ACE to regulate blood pressure. Food-derived bioactive peptides have been identified and utilised for their health-promoting abilities. The tripeptide FSY (Phe-Ser-Tyr) was identified from shrimp (Pandalus borealis) protein hydrolysate as a highly potent inhibitor of ACE activity. FSY is capable of being absorbed in the digestive tract to be transported in the blood to the receptors which is a useful feature for clinical application. Further study can provide deeper understanding of FSY potency on ACE function and may lead to drug development.</p>

<p>The cyclic pentapeptide cyclo(-Arg-Gly-Asp-d-Phe-Lys-) is a highly potent and selective inhibitor for the alphavβ3 integrin receptor. A related compound, cyclo(-Arg-Gly-Asp-d-Phe-Val), is a promising anti-cancer drug candidate- it inhibits angiogenesis and induces apoptosis in vascular cells.Cyclic RGD-containing peptides are selective antagonists of integrins, proteins that play important roles in cell-cell and cell-matrix interactions. In a suitably labelled form, these peptides may serve as useful tools for diagnostic imaging and peptide targeted therapy of some types of cancer.</p>

<p>TAT-Beclin Scrambled is a scrambled version of the peptide derived from a region of the Beclin 1 protein. The original peptide interacts with a newly identified negative regulator of autophagy, GAPR-1 (also called GLIPR2) to act as a potent inducer of autophagy. Autophagy is an essential process that maintains cellular homeostasis and carries out lysosome-mediated degradation of unwanted proteins in the cytoplasm. It is often examined when looking at disease pathways because of this regulatory function. While the immune system initiates the removal of viruses and pathogens through the autophagic pathway, some viruses (such as HIV) are able to evade this process.The scrambled sequence in this peptide means it can be used as an effective negative control in such experiments because whilst it contains the same amino acids as Beclin-1 (and thus has the same molecular weight), it does not express the same properties as the original peptide.TAT (47-57) is present due to its properties as a cell penetrating cationic peptide (CPP). It derived from the N-terminus of the Tat protein, which is a trans-activator of the transcription protein present in the human immunodeficiency virus (HIV). As a CPP, TAT (47-57) is able facilitate the delivery of the Beclin Scrambled protein across the plasma membrane.This peptide contains a GG linker between the C-terminus of TAT (47-57) and the N-terminus of Beclin Scrambled.</p>

<p>Cystatin C protein is a neutralizing protein that plays a crucial role in various biological processes. It is involved in the regulation of ornithine metabolism, glucose-6-phosphate production, and the activation of p53 protein. This protein is essential for the growth and development of cells, as it interacts with growth factors such as epidermal growth factor and histidine. Cystatin C also has binding properties with sclerostin, alpha-fetoprotein, and collagen, contributing to their stability and functionality. With its diverse functions and interactions, Cystatin C protein proves to be an integral component in Life Sciences research and applications.</p>

<p>Src is a member of the Src family tyrosine kinases (SFKs), a large cytosolic, non-receptor, kinase family that controls multiple signalling pathways in animal cells. SFKs play key roles in cell morphology and differentiation, motility, proliferation and survival. Src contains an N-terminal 14-carbon myristoyl group, a unique segment, an SH3 domain, an SH2 domain, a protein-tyrosine kinase domain and a C-terminal regulatory tail. Src is expressed ubiquitously however it is seen at far higher levels in the brain, osteoclasts, and platelets. Src is a proto-oncogene and elevated levels of Src protein are seen in different tumours including: breast- lung- thyroid- glioblastoma- colorectal- pancreatic- prostate- gastric- biliary tract, ovarian and skin cancer. Src levels are often associated with tumour progression, metastasis and a poor clinical outcome and therefore Src has been investigated as a therapeutic target.</p>

<p>The Drosophila Antennapedia homeoprotein is able to interact with the phospholipid bilayer to cross into the cell. The 16 residues of penetratin were identified that allowed translocation across the membrane of the cell in to the nucleus. Penatratin has been used as a CPP conjugate in a wide variety of fields particularly to transport hydrophilic molecules.The penetratin domain is present here fused to the green-fluorescent dye Alexa Fluor Dye 488. The tag is suitable for use in imaging and flow cytometry, excitation/ emission at 490/525nm. This fluorescent CPP can be used as a conjugate for intracellular drug delivery or detection of biological structures and thus a key research tool. This peptide is produced to research quality and therefore for research purposes only, and not for use in a therapeutic setting.</p>

<p>Alpha-1-acid glycoprotein (AAG) is one of the major proteins involved in sequestering drugs in the plasma such as: lidocaine- propranolol- verapamil- steroid hormones and phenobarbital. AAG is a member of the acute phase protein (APP) family and is formed primarily in the liver and circulates at low levels in the plasma of healthy humans. In many diseased states including inflammation, infection, and cancer, AAG levels increase from 2 to 6-fold in humans. AAG can regulate immunity and plays a role in both pro- and anti-inflammatory response.AGG forms a positive feedback loop to exert anti-fatigue functions via the CCR5 receptor and therefore AGG, and CCR5 could be novel targets for the therapeutic intervention of fatigue.The leucine residue at position 14 of this peptide is isotopically labelled with carbon-13 (6) and nitrogen-15 (1), giving this peptide a mass increase of 7 compared to the unlabelled peptide.</p>

<p>Histone H3 (1-20) K4Me2 is derived from Histone 3 (H3), which is one of the four core histones (H2A, H2B, H3 and H4) fundamental in compacting eukaryotic DNA into the nucleosome. The nucleosome arises when 147 base pairs of DNA wrap around a H3-H4 tetramer and two H2A-H2B dimers, forming the histone octamer core. H4 and H3 are highly conserved and perform roles in binding to segments of DNA which enter and leave the nucleosome and in chromatin formation. Like the other core histone, H3 has a globular domain and a flexible N-terminal domain, 'histone tail' which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination. Due to histones containing many lysine and arginine residues, they have a positive net charge which interacts electrostatically with the negatively charged phosphate groups in DNA. The transcriptional activation or silencing of the chromatin is controlled by ATP-dependent chromatin remodelling factors and histone-modifying enzymes which target histone proteins. Both processes change the positioning of the nucleosome, allowing the DNA to be either available to the transcription machinery or inaccessible.Histone tails can undergo multiple modifications, including acetylation, methylation, ubiquitylation and sumoylation.  The modification pattern is believed to alter chromatin function/structure. Histone H3 (1-20) K4Me2-GG-[Lys(5-FAM)] lysine 4 has been dimethylated, has a C-terminal GGK linker labelled with 5-Carboxyfluorescein (5-FAM), a widely used green fluorescent tag. This peptide also has an uncharged C-terminal amide. H3 (1-20) K4Me2 has been investigated to understand its effect on epigenetic regulation through NMR with histone readers such as zinc finger domains. Histone H3 (1-20) K4Me2-GG-[Lys(5-FAM)] can be used to study the function of this pattern on chromatin availability and histone effectors via crystallisation, pull-down assays and protein blots.</p>

<p>The GPBB antibody is a monoclonal antibody that specifically targets the growth factor GPBB (glycogen phosphorylase BB). This antibody has been extensively used in Life Sciences research to study the role of GPBB in various biological processes. It has been shown to inhibit the binding of GPBB to its receptors, thereby blocking downstream signaling pathways involved in cell growth and proliferation.</p>

<p>The heat shock protein 27 (HSP27) is a protein chaperone which ensure that damaged proteins are refolded into their correct conformation in the event of heat shock or other stress stimuli. In the event of oxidative stress HSP27 increases glutathione and decreases iron levels thus acting as an antioxidant. Further roles of HSP27 include, the inhibition of the apoptotic process through binding to the apoptotic proteins Bax, cytochrome C and DAXX and it also controls the actin cytoskeleton.HSP27 itself is regulated by the phosphorylation of its serine residues and this phosphorylation can alter the properties of HSP27. For example in its role in the actin cytoskeleton, when HSP27 is phosphorylated it stimulates actin filament polymerisation. Conversely when it is not phosphorylated HSP27 is an actin capping protein.HSP27 has the potential to be used as a biomarker in renal disease due to its levels being increased in renal fibrosis. It may also be used as a therapeutic target to treat cancers such as prostate carcinoma and breast cancer as it promotes tumour cell survival through inhibition of the apoptotic process. Moreover HSP27 may contribute to the treatment of neuro-degenerative diseases in that they can prevent the accumulation of misfolded proteins.The arginine residue at position 9 is isotopically labelled with carbon-13 (6) and nitrogen-15 (4).</p>

<p>Residues 1-12 of the gastrointestinal hormone motilin, secreted from endocrine cells in the small intestines, mainly from the jejunum and duodenum, in response to the fasting, drinking water or the mechanical stimulus of eating.</p>

<p>Apolipoprotein E (ApoE) is a cholesterol carrier and regulates lipid transport and cholesterol metabolism. Isoforms of ApoE have been shown to be associated with Alzheimer disease. The Leucine residue at position 12 has been isotopically labelled with carbon-13 (6) and nitrogen-15 (1).</p>

<p>Candidate peptide substrate for kallikrein-related peptidase 5 (KLK5). In its intact state this peptide is not fluorescent, however when this substrate peptide is cleaved, Rhodamine 110 is released and thus fluorescence can then be detected. Contains rhodamine 110 group, a widely used red fluorescent tag. The terminal carboxylic acids in this peptide have been activated by the addition of the p-tosyl moiety, allowing for easy addition of functional groups or further peptide residues.</p>

<p>Amyloid β-peptide (Aβ) has been identified as the key subunit of the extracellular plaques found in the brains of patients with Alzheimer's disease (AD) and Down's syndrome (DS). Aβ has therefore been extensively studied as a potential target for treatment of AD. Aβ is formed from the cleavage of the large, transmembrane protein APP (amyloid precursor protein). Cleavage of APP by β- and then γ-secretases results in the formation of Aβ. Aβ can aggregate to produce amyloid-β oligomers, which are thought to be highly neurotoxic. Over time Aβ can further aggregate to produce the characteristic senile plaques present in AD and DS. Aβ can be degraded by enzymes such as neprilysin, insulin degrading enzyme or endothelin converting enzyme. At physiological levels Aβ may be involved in controlling synaptic activity and neuronal survival.</p>

<p>The Plasmodium vivax antibody is a highly specialized product that consists of polymers designed to target and neutralize the antigen produced by the Plasmodium vivax parasite. This monoclonal antibody is specifically developed to bind to the surface proteins of the parasite, preventing its ability to invade human red blood cells and causing malaria.</p>

<p>Fibrinogen protein is a glycoprotein that plays a crucial role in blood coagulation. It is involved in the formation of fibrin, which helps to create blood clots and stop bleeding. Fibrinogen also acts as an anticoagulant by inhibiting the activation of platelets and preventing excessive clotting.</p>

<p>Autocamtide-2</p>

<p>Portion of HCMV</p>

<p>Heptapeptide containing Lysine.</p>

<p>Amino acids 1-17 of human adrenocorticotropic hormone (ACTH). ACTH, also known as corticotropin, is a tropic hormone produced and secreted by the anterior pituitary gland and member of the melanocortins peptide family. ACTH is cleaved from the precursor proopiomelanocortin (POMC). ACTH is an important component of the hypothalamic-pituitary-adrenal (HPA) axis and is often produced in response to biological stress. ACTH acts to increase the production and release of cortisol via its interaction with the ACTH receptor- ACTHR, also known as melanocortin type 2 receptor (MC2R). Receptor activation increases the intracellular concentration of cAMP via adenylyl cyclase.Abnormal ACTH levels in the body has been linked to primary adrenal insufficiency/Addison's disease, Cushing's disease and secondary adrenal insufficiency.</p>

<p>Conjugated Fentanyl-HRP hapten</p>

<p>Mucin 10 (153 - 165), EA2.</p>

<p>Histone H3 (1-22) is derived from Histone 3 (H3) which is one of the four core histones (H2A, H2B, H3 and H4) fundamental in compacting eukaryotic DNA into a structure known as the nucleosome. The nucleosome arises when 147 base pairs of DNA wrap around a H3-H4 tetramer and two H2A-H2B dimers, forming the histone octamer core. Both H4 and H3 are highly conserved and perform roles in binding to segments of DNA which enter and leave the nucleosome and in chromatin formation. Similar to the other core histone, H3 has a globular domain and a flexible N-terminal domain 'histone tail' which can undergo modifications such as acetylation, methylation, phosphorylation and ubiquitination. Due to histones containing a large number of lysine and arginine residues they have a positive net charge which interacts in an electrostatic manner with the negatively charged phosphate groups in DNA. The transcriptional activation or silencing of the chromatin is controlled by ATP-dependent chromatin remodelling factors and histone modifying enzymes which target histone proteins. Both processes function to alter the positioning of the nucleosome, allowing the DNA it to be either available or inaccessible to the transcription machinery.</p>

<p>VEGFR2 protein is a growth factor that plays a crucial role in angiogenesis, the formation of new blood vessels. It is targeted by monoclonal antibodies and recombinant proteins for various research and therapeutic applications in the field of Life Sciences. VEGFR2 protein interacts with other molecules such as angptl3, interferon, and growth hormone receptor to regulate endothelial cell proliferation and promote vascular development.</p>

<p>FdM, ferredoxin maquette is a synthetic peptide which can bind a [4Fe-4S] cluster and contains a bacterial ferredoxin consensus motif (CIACGAC).</p>

<p>Peptide obtained by linking the 11 amino acid human HIV Tat transporter to a 21 amino acid sequence corresponding to the ADAM10 proline-rich domains.</p>

<p>Heat shock proteins (Hsps) are highly conserved and stress inducible. Hsp70 has been found in tumour cell lines to be highly expressed with a higher plasma membrane localisation. This is correlated to the cell sensitivity to natural killer (NK) cell-mediated lysis. Investigation identified that Hsp70 N-terminal extended peptide TKD (450-463) was critical for this to occur. TKD (450-463) with low dose interleukin (IL-2) has the same capacity to induce NK cell proliferation and activity as the full-length protein Hsp70. Excess of Hsp70 and TKD (450-463) both inhibit cytolytic activity by NK cells. Other related sequences tested did not lead to NK cell-mediated lysis. Further study with the TKD (450-463) epitope could elucidate how NK cells are activated by Hsp70s as the mechanism remains unclear.</p>

<p>Echinotocin is a neurophysin containing precursor neuropeptide derived from the sea urchin Strongylocentrotus purpuratus.</p>

<p>GRGDS peptide</p>

<p>EB1 is a penetratin analogue that was synthesised to be an endosomolytic cell penetrating peptide (CPP). Certain amino acids in the penetratin sequence were replaced with histidine to encourage formation of an alpha helix upon protonation in the acidic endosomes. As a CPP, EB1 has been shown to form a strong interaction with the phospholipid bilayer during insertion with rapid cellular uptake, there is a moderate amount of cell leakage and no significant cytotoxicity.EB1 is provided here with a N-terminal alkyne attachment. Two of the most regularly encountered functional groups for click chemistry are azides and alkynes, and the azide-alkyne cycloaddition has become the most popular click reaction. The use of click chemistry with alkyne-EB1 allows a wide variety of applications particularly for conjugation, modification and peptide design.</p>