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Peptides for Parkinson’s disease (PD)

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How does BIRD-2 peptide kill B-cell lymphoma?

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LifeTein Launches Rush Custom Peptide Synthesis Service: Peptide Delivered in 3-5 Days

How BIRD-2 Peptide Takes Down B-Cell Lymphoma?

Posted on January 14, 2016 by LifeTein Peptide

The anti-apoptotic factor Bcl-2 is over-expressed in B-cell lymphoma cells as their main survival mechanism by binding to IP3R2 on the endoplasmic reticulum (ER). In this study, a cell-penetrating version of the BIRD-2 peptide (Bcl-2/IP3R Disrupter-2 peptide with a TAT sequence) made by LifeTein was used to break up the complex formed by Bcl-2 and IP3R2 in human diffuse large B-cell lymphoma (DLBCL) cells. Ca²⁺ signaling-related events are suggested to be the killing mechanism of BIRD-2 peptide on DLBCL cells.

BIRD-2, a peptide that specifically disrupts the Bcl2/IP3R complex, was utilized to further verify the mitochondrial Ca²⁺ regulatory mechanism via the Bmal1-Bcl2/IP3R signaling pathway. It was found that BIRD-2 aggravated mitochondrial Ca²⁺ overload and apoptosis in vitro.

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BIRD-2 peptide (sequence: RKKRRQRRRGGNVYTEIKCNSLLPLAAIVRV) was purchased from LifeTein (South Plainfield, NJ, USA) with a purity of >85%.

Bird-2 Peptides & B-Cell Lymphoma

Reference:

BIRD-2 peptide (LifeTein, USA), specifically disrupting the Bcl2/IP3R complex, was used in HGHP-treated H9c2 cells for 12 h (20 μM)

Inhibiting Bcl-2 via its BH4 domain in DLBCL cancers to provoke pro-apoptotic Ca²⁺ signaling

BIRD-2, a BH4-domain-targeting peptide of Bcl-2, provokes Bax/Bak-independent cell death in B-cell cancers through mitochondrial Ca2+-dependent mPTP opening

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Peptides for Parkinson’s disease (PD)

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ID2 peptide for inhibition of tumour growth

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LifeTein Launches Rush Custom Peptide Synthesis Service: Peptide Delivered in 3-5 Days

Look Who’s Talking

Posted on January 14, 2016 by LifeTein Peptide

Intraspecies pheromone signaling regulated by proteases is critical for fungi procreation. The fungal aspartyl protease Bar1 was shown to have unique substrate specificity of important implications in fungal evolution. LifeTein synthesized substrate peptides of Bar1, dual-tagged with DABCYL and EDANS, from the sequence of α pheromone, the native target of Bar1. Referred as internally quenched or IQ peptides, they were used in fluorescence resonance energy transfer (FRET) assays to study the enzyme kinetics of Bar1.

LifeTein’s Internally Quenched Peptides

mBio 6(6):e01604-15. doi:10.1128/mBio.01604-15. Evolutionary selection on barrier activity: Bar1 is an aspartyl protease with novel substrate specificity.

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Peptides for Parkinson’s disease (PD)

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ID2 peptide for inhibition of tumour growth

How does BIRD-2 peptide kill B-cell lymphoma?

LifeTein Launches Rush Custom Peptide Synthesis Service: Peptide Delivered in 3-5 Days

A New Patent Using Peptides

Posted on January 14, 2016 by LifeTein Peptide

A patent has been published that describes new methods of manipulating plant stomatal development through artificially controlling how CRSP is expressing in plant cells. The cleavage of epidermal patterning factor 2 (EPF2) by a serine protease CRSP is a key regulating mechanism in plant stomatal development. A 30-mer EPF2 peptide, dual-tagged with DABCYL and EDANS, was synthesized by LifeTein to evaluate the protease activity of synthetic CRSP in a FRET assay.

New Patent Using Peptides Synthesized By LifeTein

Compositions and methods for mediating plant stomatal development in response to carbon dioxide and applications for engineering drought tolerance in plants.

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Nanoparticles Get Help from Cell-Permeable Peptides

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A tumor-permeable peptide iRGD by LifeTein targets peritoneal carinomatosis

Nanoparticles Get Help from Cell-Permeable Peptides

Posted on January 14, 2016 by LifeTein Peptide

Some cell-permeable peptides are able to carry cargos across cell membrane even without any covalent links. Biotinylated peptides, including L- and D-TAT peptides made by LifeTein were used in this study to show that two types of cell surface receptors, heparan sulfate proteoglycans and Neuropilin-1, play critical roles in the delivery of silver-based nanoparticles into cells by cell-permeable peptides.

Nano Particles & Cell-Permeable Peptides

Science Advances 06 Nov 2015: Vol. 1, no. 10, e1500821 DOI: 10.1126/sciadv.1500821. Neuropilin-1 and heparan sulfate proteoglycans cooperate in cellular uptake of nanoparticles functionalized by cationic CPP peptides.

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A tumor-permeable peptide iRGD by LifeTein targets peritoneal carinomatosis

Predicting type 1 diabetes in children

Posted on January 14, 2016 by LifeTein Peptide

MAP is a pathogenic bacterium infecting livestock and found prevalent in dairy products. Because some of its proteins are sequentially homologous to human zinc transporter 8 (ZnT8) protein and proinsulin (PI), children could develop autoimmunity against ZnT8 and PI after being exposed to MAP in dairy foods, and generating antibodies against MAP, and might subsequently develop type I diabetes. The hypothesis was tested by using ZnT8, PI and MAP peptides synthesized by LifeTein to assess the cross-reactivity of antibodies in sera samples from at-risk children.

Type 1 Diabetes in Children

Journal of Diabetes Research, Article ID 5842701, in press. Recognition of ZnT8, Proinsulin, and Homologous MAP Peptides in Sardinian Children at Risk of T1D Precedes Detection of Classical Islet Antibodies.

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Nanoparticles Get Help from Cell-Permeable Peptides

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A tumor-permeable peptide iRGD by LifeTein targets peritoneal carinomatosis

Advancing Cancer Treatment with LifeTein’s Peptide Synthesis in Antibody Therapy

Posted on January 14, 2016 by LifeTein Peptide

LifeTein’s Role in Overcoming Cetuximab Resistance in Colorectal Cancer

In the ongoing battle against cancer, monoclonal antibody therapies have emerged as a beacon of hope. Cetuximab, a therapeutic monoclonal antibody, has been developed to halt tumor growth by targeting the extracellular domain of the Epidermal Growth Factor Receptor (EGFR) on cancer cells’ surfaces. However, the emergence of resistance to cetuximab in clinical settings has posed a significant challenge.

Researchers have made a breakthrough using peptides synthesized by LifeTein to address this critical issue. By incorporating methylated arginine residues into these peptides, scientists successfully generated specific antibodies in mice. This innovative approach led to the discovery that Arg198 and Arg200 of EGFR undergo methylation by protein arginine methyltransferase 1 (PRMT1) in colorectal cancer cells. This methylation is now understood to be a key factor in the development of resistance to cetuximab.

The findings, published in the Journal of Clinical Investigation (2015;125(12):4529-4543. doi:10.1172/JCI82826), highlight the potential of PRMT1-mediated methylation of the EGF receptor as a target for overcoming cetuximab resistance. This research paves the way for developing more effective treatments for cancer patients, marking a significant advancement in the field.

LifeTein’s Comprehensive Peptide Synthesis Services

LifeTein’s contribution to this groundbreaking research is part of their broader commitment to advancing scientific discovery through their peptide synthesis services. Their offerings include:

COVID-19 Services & Products: Addressing the urgent needs of the pandemic.
Custom Antibody Services: Tailored solutions for specific research needs.
Rush Peptide Synthesis: Accelerated synthesis for time-sensitive projects.
Peptide Nucleic Acids (PNAs): Offering versatility in genetic research.
Custom Peptide Synthesis Services: Expertise in synthesizing complex peptides.
Gene Synthesis Service: Advanced techniques for precise gene construction.
Custom Chemical Synthesis: Broadening the scope of molecular innovation.

Exploring Other Innovations by LifeTein

LifeTein is not just limited to cancer research. Their expertise in peptide synthesis has led to various other significant contributions in the biomedical field:

Nanoparticles Enhanced by Cell-Permeable Peptides: LifeTein’s peptides are instrumental in improving the delivery and efficacy of nanoparticles in therapeutic applications.
Predicting Type 1 Diabetes in Children: Leveraging peptide technology, LifeTein is at the forefront of developing predictive tools for early detection of type 1 diabetes in pediatric populations.
Targeting Peritoneal Carcinomatosis with iRGD Peptide: The tumor-permeable peptide iRGD, synthesized by LifeTein, is a promising agent in targeting peritoneal carcinomatosis, enhancing drug delivery to tumor sites.
Simplifying and Enhancing Biosensors: LifeTein’s peptides play a crucial role in developing simpler, more efficient biosensors, pushing the boundaries of diagnostic technology.
Innovative Patents Using Peptides: LifeTein’s cutting-edge research has led to new patents in peptide-based technologies, showcasing their commitment to innovation and scientific advancement.

LifeTein’s pivotal role in overcoming cetuximab resistance in colorectal cancer is a testament to its expertise in peptide synthesis and its applications in medical research. Their diverse range of services and contributions to various fields underscore their commitment to advancing scientific knowledge and developing solutions for pressing health challenges. As LifeTein continues to explore the frontiers of peptide synthesis, their work not only illuminates the path to better cancer treatments but also opens doors to new possibilities in biomedical research and therapeutics.

To Make Simpler and Better Biosensors

Posted on January 14, 2016 by LifeTein Peptide

In order to improve the design of immunosensors, fluorophores were conjugated on to the single chain Fv (scFv) fragment of a recombinant anti-BGP antibody to form Quenchbodies (Q-bodies), in which their fluorescence is internally quenched by Trp residues of scFv. Unlabeled and biotinylated BGP peptides made by LifeTein were used in ELISA and FRET assays as the ligand to evaluate the quality of Qbodies, and to demonstrate the antigen-dependent fluorescence of Qbodies.

Making Simpler & Better Biosensors

ACS Sensors, Article ASAP. DOI: 10.1021/acssensors.5b00089. Q-Bodies from Recombinant Single-Chain Fv Fragment with Better Yield and Expanded Palette of Fluorophores.

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Nanoparticles Get Help from Cell-Permeable Peptides

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A tumor-permeable peptide iRGD by LifeTein targets peritoneal carinomatosis

A tumor-penetrating peptide enhances circulation-independent targeting of peritoneal carcinomatosis, Journal of Controlled Release, Volume 212, 28 August 2015, Pages 59–69

Innovative Tumor-Permeable Peptide iRGD Targets Cancer with Precision

Posted on July 13, 2015 by LifeTein Peptide

A tumor-penetrating peptide, iRGD, was synthesized by LifeTein. It was found that iRGD improves tumor-specific penetration of intraperitoneal compounds and enhances intraperitoneal chemotherapy (IPC) in mice. This penetration was tumor-specific. When the FITC was attached to iRGD and mixed with nanoparticles, the mixture could penetrate into fresh human peritoneal metastasis explants. The evidence proved that the LifeTein iRGD enhanced intratumoral entry. The intraperitoneal iRGD co-administration is a simple and effective strategy to facilitate tumor detection and potential application for therapeutic improvement.

LifeTein’s Peptide: iRGD

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Peptide Applications

Posted on June 2, 2015 by LifeTein Peptide

Peptides can be used in a wide variety of research applications:

Anti-microbial Peptides

81 oligopeptides were synthesized by LifeTein and tested for inhibition of Enterococcus faecalis V583. Three peptides were found to inhibit V583. The peptide (NH2-VAVLVLGA-COOH) possessed activity in picomolar concentrations, being >10^6 -fold more active than the only other two and showing inhibitory activity. Pheromone killing of multidrug-resistant Enterococcus faecalis V583 by native commensal strains, PNAS, 2015 The fungal pathogen causes the skin disease for amphibians. Use of a potent antibiotic cocktail dramatically reduced culturable skin bacteria within 48 h. The synthetic peptides by LifeTein were used to reduce the skin bacteria. SSkin bacteria provide early protection for newly metamorphosed southern leopard frogs (Rana sphenocephala) against the frog-killing fungus, Batrachochytrium dendrobatidis, Biological Conservation, 2015

Anti-inflammatory Peptides

Anti-inflammatory peptides were isolated from alcalase hydrolysates out of tuna cooking juice by-product. Synthetic peptides from LifeTein were used to confirm the inhibitory anti-inflammatory activity. The amino acid sequences of the two anti-inflammatory peptides isolated from AH hydrolysates were Pro-Arg-Arg-Thr-Arg-Met-Met-Asn-Gly-Gly-Arg (1543.8 Da) and Met-Gly-Pro-Ala-Met-Met-Arg-Thr-Met-Pro-Gly (1211.5 Da).

Epitope Mapping

Peptide scanning involves the chemical synthesis of overlapping peptides covering the antigen sequence targeted by the investigated antibodies. Peptide truncations are used to further narrow down the epitope sequence and mutagenesis of each amino acid such as alanine substitution can also indicate the binding affinity. Cross-reactive epitopes were found in Borrelia burgdorferi p66. Cross-reactive epitopes in Borrelia burgdorferi p66, Clinical and Vaccine Immunology, 2015

Cell Penetrating Peptides and Scrambled Peptides

The CD81 peptides tagged with cell penetrating peptide RRRRRRR were used for the binding assay. The synthetic peptides from LifeTein were used to investigate the role of CD81 in the regulation of defense mechanisms against microbial infections. The scrambled peptides, RRRRRRR- CCGIRNSSVY, were used as the negative control for the study. CD81 Controls Immunity to Listeria Infection through Rac-Dependent Inhibition of Proinflammatory Mediator Release and Activation of Cytotoxic T Cells, The Journal of Immunology, 2015

Receptor Binding Study

His-tagged GLP-1 (7-36), glucagon, and gastric inhibitory polypeptides (GIP) by LifeTein were used to study GLP-1 receptor signaling regulation. The GLP-1 peptides bind specifically with lipids but not that of exendin 4.The His-Tagged GLP-1 were used for the binding reaction. The free peptide was captured by Cu++-NTA resin. The results indicated that His-tagged GLP-1 peptide binds to OEA in a dose-dependent and saturable way. Modulation of Glucagon-like Peptide (GLP)-1 Potency by Endocannabinoid-like Lipids Represents A Novel Mode of Regulating GLP-1 Receptor Signaling. Journal of Biological Chemistry, 2015

Antibody Blocking Peptides

Peptides can be used as blocking peptides for the competition assay. The excess of blocking peptides (20:1 peptide: antibody ratio) from LifeTein were mixed with antibodies. The antibody was neutralized in this way by incubating with an excess of peptide that corresponds to the epitope recognized by the antibody. The neutralized antibody is then used side-by-side with the antibody alone, and the results are compared. Whole Exome Sequencing Reveals ZNF408 as a New Gene Associated With Autosomal Recessive Retinitis Pigmentosa with Vitreal Alterations, Human Molecular Genetics, 2015

Protein-Protein Interactions

The B-cell lymphoma 2 (Bcl-2) peptides were biotinylated at N terminus for the protein-protein interactions. The biotin-BH4-Bcl-XL peptide and the scrambled peptide were immobilized on different channels of a streptavidin-coated sensor chip. Studies showed that Bcl-XL bound to the central domain of RyR3 via its BH4 domain. Further analysis of a mutated peptide at a specific site Lys87 showed a reduced binding affinity. These data suggest that BH4 domain and its specific site of Lys87 contributes to the interaction. Ryanodine receptors are targeted by anti-apoptotic Bcl-XL involving its BH4 domain and Lys87 from its BH3 domain, Nature Scientific Reports, 2015