Lyme disease is an abundantly present vector-born disease, with nearly 400,000 new cases in the U.S. diagnosed each year. While treatment with antibiotics is effective, if the disease goes unnoticed and unchecked it can lead to lifelong damage to the nervous and musculoskeletal system. Hence, it is critical to detect the disease as early as possible, however this becomes a complex issue since not every case results in erythema migrans (EM), the characteristic skin lesion of Lyme disease. This issue is further complicated since current serodiagnostics lack sensitivity in early Lyme disease detection, when treatment would be the most effective. One group sought to solve this issue by developing a method more sensitive and more specific than the current ones, ultimately using linear peptide epitomes to better diagnose Lyme disease.

Linear peptide epitomes lead to higher specificity and sensitivity in Lyme disease assays

LifeTein synthesized peptides from prominent B. burgdorferi antigens expressed during human infection of Lyme disease for the group to utilize. Their idea is to use synthetic peptides that contain the linear epitomes necessary, rather than protein antigens that often have cross-reactive epitomes. Eliminating the cross-reactive epitomes leads to more specificity within the tests, and more sensitivity as well. While the results for the single peptide epitomes were less than anticipated, the group found that using the epitome peptides in pairs resulted in the specificity and sensitivity they had hypothesized.

Diagnostic assessment of Lyme disease is in dire need of an improvement to efficiently catch it in the early stages, and these linear peptide epitomes are shaping to be a key part of the solution. The group hopes that their research will allow future works to improve upon their studies and one day include the linear peptide epitomes as part of a potential multi-peptide-based assay for the laboratory diagnosis of Lyme disease.

Arnaboldi PM, Katseff AS, Sambir M, Dattwyler RJ. Linear Peptide Epitopes Derived from ErpP, p35, and FlaB in the Serodiagnosis of Lyme Disease. Pathogens. 2022; 11(8):944. https://doi.org/10.3390/pathogens11080944

As the world moves on through the ongoing pandemic that is COVID-19, great minds across every field and corner of the world are doing their part to further our collective understanding of the virus. A recent study specifically took greater notice in the population of antibodies increasing in more sever cases of COVID-19 over mild ones. Specifically, there was a study conducted on the higher HERV-W and IFN-I antibody presence detected in intensive care COVID-19 patients, utilizing peptides for the experiment.

HERV-W and IFN-I antibody presence higher in severe COVID-19 cases

LifeTein supplied the group with the HERV-W-env(248–262), IFN-α, and IFN-ω peptides necessary for the report. Not only did the studies prove higher levels of anti-IFN-I autoantibodies and HERV-W antibodies are much more prevalent in severe COVID-19 cases than in mild ones, but it opened up a new perspective on how the humoral responses against HERV-W-env(248–262) and IFN-α are correlated across ICU patients. Hopefully, this research leads to more beneficial breakthroughs over time, for COVID-19 cases and potentially other life-threatening conditions as well.

Simula, E. R., Manca, M. A., Noli, M., Jasemi, S., Ruberto, S., Uzzau, S., Rubino, S., Manca, P., & Sechi, L. A. (2022). Increased Presence of Antibodies against Type I Interferons and Human Endogenous Retrovirus W in Intensive Care Unit COVID-19 Patients. In H. H. Mostafa (Ed.), Microbiology Spectrum. American Society for Microbiology. https://doi.org/10.1128/spectrum.01280-22

Platinum based anticancer drugs generally go hand-in-hand with DNA, however their interactions with proteins are important to understand as well. A group focused their work on discovering and further exploring binding sites of cisplatin onto both an oligonucleotide and two peptides corresponding to segments of H2A and H2B histone proteins via mass spectrometry. The study revealed key interactions and the mechanism of cisplatin binding with oligonucleotides and peptides, and eventually DNA as well.

Peptide and oligonucleotide competitive binding with platinum

LifeTein supplied the group with two peptides for the project; P1, from the acidic region of H2a, and P2, from the α2-helix of H2B human histone protein. These peptides and an oligonucleotide model of DNA were analyzed using electrospray ionization high-resolution mass spectrometry and tested with substantial theoretical figures to match the fragments. Here the group found the preferred binding sites on both of the peptides and the oligonucleotide, of relevance are the multiple histidine and methionine residues on P2 that saw the most binding to cisplatin over P1.

The adducts formed on platinated P2 were tested and incubated solely with the oligonucleotide, where after two days the group found that a portion of the platinum fragments had migrated from the peptide to the oligonucleotide. This observation not only showed that the oligonucleotide was perhaps the more thermodynamically favored product, but also gave insight into how the cisplatin drug takes to DNA during chemotherapy, by binding to the proteins first and then reversing the reaction and migrating. The long-term implications of this mechanism will surely be researched and explored in the future of platinum drug delivery and cancer treatment.

Mansouri, F., Patiny, L., Ortiz, D. et al. Simultaneous mass spectrometry analysis of cisplatin with oligonucleotide-peptide mixtures: implications for the mechanism of action. J Biol Inorg Chem 27, 239–248 (2022). https://doi.org/10.1007/s00775-022-01924-9

After the gut, the mouth is the most important microbiome in the human body, with the inhabitants ranging from bacteria and fungi to viruses and protozoa. If this careful balance of microorganisms is thrown off even by a little, certain pathogens could propagate and cause serious periodontal diseases. One such pathogen is Porphyromonas gingivalis (P. gingivalis), which degrades the specialized basal lamina components that protect supporting teeth tissues. However, one component of this specialized basal lamina, the secretory calcium-binding phosphoprotein proline-glutamine rich 1 (SCPPPQ1) protein, had shown to be not only resistant to P. gingivalis, but also to affect the cell membrane of P. gingivalis itself. A group of researchers then decided to explore the antimicrobial properties of the SCPPPQ1 protein and its peptide derivatives.

SCPPPQ1 protein and peptide derivatives as antibacterial agents

Using the SCPPPQ1 protein itself and derived peptides synthesized by LifeTein, the group sought to test how they fared against P. gingivalis in isolated conditions. After incubating the two together, results showed a rapid and significant decrease of P. gingivalis population. The means of which were narrowed down to aggregation of bacteria and membrane disruption.

The group went further and tested the antibacterial properties against other pathogens, and though there were results, none were as significant as those against P. gingivalis. The results point towards a more honed treatment against P. gingivalis using this knowledge of the SCPPPQ1 protein and its peptide derivatives. Since the protein itself is native to the human mouth, further application to treat periodontal pathogens with its antibacterial properties is not out of the question.

Mary, C., Fouillen, A., Moffatt, P. et al. Effect of human secretory calcium-binding phosphoprotein proline-glutamine rich 1 protein on Porphyromonas gingivalis and identification of its active portions. Sci Rep 11, 23724 (2021). https://doi.org/10.1038/s41598-021-02661-w

Peptide nucleic acids (PNAs) are synthetic mimics of DNA.  The deoxyribose phosphate backbone of PNAs is replaced by a pseudo-peptide polymer. These specific physicochemical properties are exploited to develop a wide range of powerful biomolecular tools, including molecular probes, biosensors, and antigene agents. The PNA molecules can routinely be labeled with biotin, azido, cell penetration peptide fragments, or fluorophores such as FITC, Cy3, Cy5, Cy7, Alexa Dyes, and pyrene.

The uncharged synthetic backbone provides PNA with unique hybridization characteristics. It gives higher stability, or a higher thermal melting temperature (Tm) to the PNA–DNA or PNA–RNA duplexes than the natural homo- or heteroduplexes. In addition, the unnatural backbone of PNAs is not degraded by nucleases or proteases.

It was shown that the binding of PNA to complementary DNA can efficiently block transcriptional elongation and inhibit the binding of transcriptional factors. Thus, the PNAs can be used as antisense or antigene therapeutic agents. PNAs can be used as adapters to link peptides, drugs, or molecular tracers to plasmid vectors. One concept is to form the duplexes of PNAs – cell penetration peptides. The duplexes can penetrate into cells and be used in anticancer applications. The nuclear localization signal (NLS) peptide-PNAs duplexes gave a much higher nuclear localization of a coupled nuclear localization signal than did the free oligonucleotide.

The strategy of PNA-directed PCR clamping is used to inhibit the amplification of a specific target. This PNA–DNA complex formed at one of the primer sites effectively blocks the formation of the PCR product. The procedure can be used to detect single base-pair gene variants for mutation screening and gene isolation. The biotinylated short PNA probes can be used as generic capture probes for the purification of nucleic acids via streptavidin beads. Other applications could be solid-phase hybridization, and fluorescence in situ hybridization (PNA-FISH).

PNA-based applications benefit from the unique Physico-chemical properties of PNA molecules, enabling the development of cell penetration peptide-PNA assays in molecular genetics. 

Reference

Adult type 2 diabetics are at very high risk of obesity-associated hypertension, where the end result can be as grave as heart failure. The systems involved in the human body regarding these conditions can be complex, but scientists have identified cases of stroke and refractory hypertension that harbored increased plasma IgG, 5-hydroxytryptamine 2A receptor (5-HT2AR)-targeting autoantibodies.

Serotonin 2A-Receptor Decoy Peptide Lowers Blood Pressure

The goal was to test whether a decoy receptor peptide could lower blood pressure in an animal model of obesity-associated hypertension. The team developed the decoy receptor peptide, SCLLADDN (Sertuercept), and LifeTein synthesized it successfully for the project. Using Zucker hypertensive diabetic fatty rats as the model, the team proved their theory.

Results showed after implementing the decoy receptor peptide, acute and long-lasting significant systolic and diastolic blood pressure-lowering occurred within the rat models. This followed through without any long-term side effects after chronic administration. Hopefully, these results are fruitful in later applications and the same peptide can be used to help significantly lower blood pressure in humans afflicted with type 2 diabetes as well.


Zimering MB. A Serotonin 2A-Receptor Decoy Peptide Potently Lowers Blood Pressure in Male Zucker Diabetic, Fatty, Hypertensive Rats. Endocrinology, Diabetes and Metabolism Journal. 2021 Aug;5(2). DOI: 10.31038/edmj.2021523. PMID: 35035793; PMCID: PMC8759716.

A linear synthetic peptide, SCLLADDN (SN..8 or P4) having a sequence
identical to that of a fragment of the second extracellular loop region of the human 5-
hydroxytryptamine 2A receptor was synthesized at Lifetein, Inc (Hillsborough, NJ) and
had > 95% purity. Substitutions of SCLLADDN containing a single alanine amino acid
replacement, e.g. SALLADDN, SCLLADAN were synthesized at Lifetein, Inc (Hillsborough,
NJ) and had purity of > 95%.

Grinberg, M.; Burton, J.; Pang, K.C.; Zimering, M.B. Neuroprotective Effects of a Serotonin Receptor Peptide Follow-ing Sham vs. Mild Traumatic Brain Injury in the Zucker Rat. Preprints 2023, 2023050004. https://doi.org/10.20944/preprints202305.0004.v1

Alzheimer’s disease as we know it today is a horrible and currently incurable neurodegenerative disorder characterized by neuronal loss, memory impairment, and cognitive decline. Ongoing research is always looking for ways to combat or slow down this disorder, and one such area of interest is the related formation of senile amyloid plaques mainly composed of amyloid β (Aβ) peptides, whose aggregation is thought to be responsible for Alzheimer’s disease pathology. Researchers are implementing gallium nitride nanoparticles as a means to inhibit the formation of the Aβ40 amyloid peptides.


Gallium nanoparticles inhibit amyloid β peptide formation

LifeTein supplied the scientists with the Aβ40 peptide necessary for this research, where they would synthesize their nanoparticle with gallium nitrate and observe its inhibition on the peptide in vitro. Gallium nitrate in particular is of interest due to its biocompatibility and aqueous stability, allowing the substance to be useful in numerous biological applications.

After observing their interactions together using the likes of ThT fluorescence, CR absorbance, turbidity, and SEM imaging, the group concluded that the nanoparticle did in fact inhibit the crucial oligomeric nucleus formation of the amyloid β peptide. The group believes a key factor in this is the polarization characteristic of the nanoparticle, where even more polarization could mean more interaction between the nanoparticle and the peptide, and thus less intermolecular interactions among the Aβ40 peptide monomers to form amyloids. Hopefully the future sees more studies on these gallium nitrate nanoparticles, and how further modifications could benefit the fight against Alzheimer’s through these critical Aβ40 peptides.

Torres, K. M., Delgado, A. S., Serrano, E. R., Falcón-Cruz, N. V., Meléndez, A., Ramos, I., Du, D., & Oyola, R. (2021). Gallium nanoparticles as novel inhibitors of Aβ40 aggregation. In Materials Advances (Vol. 2, Issue 16, pp. 5471–5478). Royal Society of Chemistry (RSC). https://doi.org/10.1039/d1ma00461a

A SARS-CoV-2-specific serological assay is necessary as the global pandemic persists. The ability of such an assay to quantify virus antibodies in high and low COVID-19 incidence communities has a multitude of benefits. These include assessment of exposure rates to the virus, the immune responses to vaccination, and the longevity of antibodies from either infection or vaccination.

Spike Protein Peptide Helps Develop Multiplex Assay

Scientists used multiple resources to develop their SARS-CoV-2 specific serological assay, including a synthetic peptide of the RBD region of the Spike protein (synthetic RBD) by LifeTein. Overall, the assay proved highly sensitive and specific in monitoring the immune response and antibodies in both individuals and communities.

Some innate limitations to this kind of assay would be cross-reactivity with other human coronaviruses, though this was not an issue in the small control group used in Ithaca. The amount of information attainable from the assay will help immensely in the future of this pandemic, as being able to assess infection risks in the population will save countless through precautions.

Guarino C, Larson E, Babasyan S, Rollins A, Joshi LR, Laverack M, et al. (2022) Development of a quantitative COVID-19 multiplex assay and its use for serological surveillance in a low SARS-CoV-2 incidence community. PLoS ONE 17(1): e0262868. https://doi.org/10.1371/journal.pone.0262868