Peptides

Peptide H-QQTVTLLPAADLDDFSK^-OH is a Research Peptide with significant interest within the field academic and medical research. This peptide is available for purchase at Cymit Quimica in multiple sizes and with a specification of your choice.

The coronavirus (CoV) nucleoprotein is the major component of CoV structural proteins. The nucleoprotein has a critical role in virus assembly and RNA transcription. The nucleoprotein is essential in the formation of helical ribonucleoproteins and in regulating viral RNA synthesis. The nucleoprotein can also regulate infected host cellular mechanisms. It is highly expressed during infection and may induce protective immune responses against SARS-CoV and SARS-CoV-2.The nucleoprotein residues FKDQVILLNKHIDAY (346-360) 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.

Forms of inherited muscular dystrophy such as Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) result from mutations targeting the dystrophin gene. These disorders are X-linked, progressive, and cause the gradual weakening of the muscles leading to respiratory failure and ultimately reduces the patient lifespan.In DMD, mutations lead to the production of premature stop codons and hence the truncated dystrophin protein product is vulnerable to nonsense mediated decay and degradation. Therefore, dystrophin production in muscle cells is reduced. On the other hand, nonsense mutations which also contribute to DMD, cause exon skipping in BMD and result in an internally truncated protein product which are partially functional. The symptoms of BMD are later onset compared with DMD which develop in patients between 2 to 7 years.Treatments of dystrophin disorders are in clinical trials including antisense oligonucleotide exon skipping and gene therapy. However, the efficacies of these treatments are not easily quantified. Currently levels of muscular dystrophin are quantified by western blot which can be unreliable. The peptide provided here, aligning residues dystrophin (50-61), has been used to try and create a quantifiable method that is reproducible. The method used was not successful, but dystrophin (50-61) remains a useful tool to create a potential quantification method for diagnosis and progress of dystrophin disorders as it was effectively detected by mass spectrometry and Western blot. Within our catalogue we also have other peptides tested for dystrophin quantification available plus the full-length dystrophin protein.

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 VQIDRLITGR (991-1000) 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.

The Histone H3 (22-30)-K27Me3 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. 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 to change the positioning of the nucleosome, allowing the DNA it to be either available to the transcription machinery or inaccessible.The Histone H3 (20-36) lysine 27 has been trimethylated which is usually a marker of repressive chromatin. H3K27 trimethylation also prevents H3 from interacting with SET1-like complexes, thus inhibiting the trimethylation of H3K4.

VP4 is a viral coat protein of Nora virus encoded for by ORF4. The product of this gene is likely cleaved into three capsid proteins, VP4A, B and C. VP4 is also the most conserved gene from Nora virus and related viruses. Nora virus is a non-pathogenic virus found in gut of Drosophila melanogaster. It causes persistent, non-pathological infection, it replicates in the fly gut and is transmitted via the faecal-oral route. Nora virus has a 12333 nucleotides long single-stranded RNA genome of positive polarity.

Endogenous peptide GPR83 agonist derived from processing of precursor protein, proSAAS. It is widely expressed in a number of species where it is involved in feeding, stress modulation and addiction and reward circuits.

Influenza virus budding from infected cells requires membrane remodelling, is a multistep process with many proteins involved. Therefore there are numerous stages and proteins that could be antiviral targets if the mechanism can be better understood.The matrix 2 (M2) protein has recently been shown to be essential for completion of membrane scission at the end of buddinng. Initially, proteins aid membrane curvature, including matrix 2 (M2) protein, a bud forms, and finally membrane scission occurs to release the bud at the neck from the membrane occurs- M2 amphipathic helix domain in the cytoplasmic tail is essential for completion of scission to release the virus bud. The residues 44-62, provided here, have been identified as the motif responsible for allowing the scission mechanism to occur. Work is ongoing to understand the exact molecular mechanism by comparison to other scission proteins such as Arf1, Epsin1. Use of this M2 peptide motif may provide functional knowledge of virus budding and lead to novel antiviral drugs.