Home » Publications

Publications

Discover how PEPperPRINT Peptide Microarray products have been used in different fields of research.

Binding epitope for recognition of human TRPM4 channel by monoclonal antibody M4M

Wei, Shunhui; Behn, Julian; Poore, Charlene Priscilla; Low, See Wee; Nilius, Bernd; Fan, Hao; Liao, Ping
Sci Rep.
Nov 2022
Abstract Mouse monoclonal antibody M4M was recently designed to block human TRPM4 channel. The polypeptide for generating M4M is composed of peptide A1 between the transmembrane segment 5 (S5) and the pore, and a second peptide A2 between the pore and the transmembrane segment 6 (S6). Using peptide microarray, a 4-amino acid sequence EPGF within the A2 was identified to be the binding epitope for M4M. Substitution of EPGF with other amino acids greatly reduced binding affinity. Structural analysis of human TRPM4 structure indicates that EPGF is located externally to the channel pore. A1 is close to the EPGF binding epitope in space, albeit separated by a 37-amino acid peptide. Electrophysiological study reveals that M4M could block human TRPM4, but with no effect on rodent TRPM4 which shares a different amino acid sequence ERGS for the binding motif. Our results demonstrate that M4M is a specific inhibitor for human TRPM4.

A heterotypic assembly mechanism regulates CHIP E3 ligase activity

Das, Aniruddha; Thapa, Pankaj; Santiago, Ulises; Shanmugam, Nilesh; Banasiak, Katarzyna; Dąbrowska, Katarzyna; Nolte, Hendrik; Szulc, Natalia A; Gathungu, Rose M; Cysewski, Dominik; Krüger, Marcus; Dadlez, Michał; Nowotny, Marcin; Camacho, Carlos J; Hoppe, Thorsten; Pokrzywa, Wojciech
The EMBO Journal.
Aug 2022
CHIP (C‐terminus of Hsc70‐interacting protein) and its worm ortholog CHN‐1 are E3 ubiquitin ligases that link the chaperone system with the ubiquitin‐proteasome system (UPS). CHN‐1 can cooperate with UFD‐2, another E3 ligase, to accelerate ubiquitin chain formation; however, the basis for the high processivity of this E3s set has remained obscure. Here, we studied the molecular mechanism and function of the CHN‐1–UFD‐2 complex in Caenorhabditis elegans. Our data show that UFD‐2 binding promotes the cooperation between CHN‐1 and ubiquitin‐conjugating E2 enzymes by stabilizing the CHN‐1 U‐box dimer. However, HSP70/HSP‐1 chaperone outcompetes UFD‐2 for CHN‐1 binding, thereby promoting a shift to the autoinhibited CHN‐1 state by acting on a conserved residue in its U‐box domain. The interaction with UFD‐2 enables CHN‐1 to efficiently ubiquitylate and regulate S‐adenosylhomocysteinase (AHCY‐1), a key enzyme in the S‐adenosylmethionine (SAM) regeneration cycle, which is essential for SAM‐dependent methylation. Our results define the molecular mechanism underlying the synergistic cooperation of CHN‐1 and UFD‐2 in substrate ubiquitylation.

Histatin 5 binds to Porphyromonas gingivalis hemagglutinin B (HagB) and alters HagB-induced chemokine responses

Borgwardt, Derek S.; Martin, Aaron D.; Van Hemert, Jonathan R.; Yang, Jianyi; Fischer, Carol L.; Recker, Erica N.; Nair, Prashant R.; Vidva, Robinson; Chandrashekaraiah, Shwetha; Progulske-Fox, Ann; Drake, David; Cavanaugh, Joseph E.; Vali, Shireen; Zhang, Yang; Brogden, Kim A.
Sci Rep.
Jan 2014
Histatins are human salivary gland peptides with anti-microbial and anti-inflammatory activities. In this study, we hypothesized that histatin 5 binds to Porphyromonas gingivalis hemagglutinin B (HagB) and attenuates HagB-induced chemokine responses in human myeloid dendritic cells. Histatin 5 bound to immobilized HagB in a surface plasmon resonance (SPR) spectroscopy-based biosensor system. SPR spectroscopy kinetic and equilibrium analyses, protein microarray studies and I-TASSER structural modeling studies all demonstrated two histatin 5 binding sites on HagB. One site had a stronger affinity with a KD1 of 1.9 μM and one site had a weaker affinity with a KD2 of 60.0 μM. Binding has biological implications and predictive modeling studies and exposure of dendritic cells both demonstrated that 20.0 μM histatin 5 attenuated (p < 0.05) 0.02 μM HagB-induced CCL3/MIP-1α, CCL4/MIP-1β and TNFα responses. Thus histatin 5 is capable of attenuating chemokine responses, which may help control oral inflammation.

Sensing Immune Responses with Customized Peptide Microarrays

Schirwitz, Christopher; Loeffler, Felix F.; Felgenhauer, Thomas; Stadler, Volker; Breitling, Frank; Bischoff, F. Ralf
Biointerphases.
Aug 2012
The intent to solve biological and biomedical questions in high-throughput led to an immense interest in microarray technologies. Nowadays, DNA microarrays are routinely used to screen for oligonucleotide interactions within a large variety of potential interaction partners. To study interactions on the protein level with the same efficiency, protein and peptide microarrays offer similar advantages, but their production is more demanding. A new technology to produce peptide microarrays with a laser printer provides access to affordable and highly complex peptide microarrays. Such a peptide microarray can contain up to 775 peptide spots per cm², whereby the position of each peptide spot and, thus, the amino acid sequence of the corresponding peptide, is exactly known. Compared to other techniques, such as the SPOT synthesis, more features per cm² at lower costs can be synthesized which paves the way for laser printed peptide microarrays to take on roles as efficient and affordable biomedical sensors. Here, we describe the laser printer-based synthesis of peptide microarrays and focus on an application involving the blood sera of tetanus immunized individuals, indicating the potential of peptide arrays to sense immune responses.

Physical Characterization of the “Immunosignaturing Effect”

Stafford, Phillip; Halperin, Rebecca; Legutki, Joseph Bart; Magee, Dewey Mitchell; Galgiani, John; Johnston, Stephen Albert
Mol Cell Proteomics.
Apr 2012
Identifying new, effective biomarkers for diseases is proving to be a challenging problem. We have proposed that antibodies may offer a solution to this problem. The physical features and abundance of antibodies make them ideal biomarkers. Additionally, antibodies are often elicited early in the ontogeny of different chronic and infectious diseases. We previously reported that antibodies from patients with infectious disease and separately those with Alzheimer’s disease display a characteristic and reproducible immunosignature on a microarray of 10,000 random sequence peptides. Here we investigate the physical and chemical parameters underlying how immunosignaturing works. We first show that a variety of monoclonal and polyclonal antibodies raised against different classes of antigens produce distinct profiles on this microarray and the relative affinities are determined. A proposal for how antibodies bind the random sequences is tested. Sera from vaccinated mice and people suffering from a fugal infection are individually assayed to determine the complexity of signals that can be distinguished. Based on these results, we propose that this simple, general and inexpensive system could be optimized to generate a new class of antibody biomarkers for a wide variety of diseases.

Quote form