Detection and quantification of free sulfhydryls in monoclonal antibodies using maleimide labeling and mass spectrometry.
AuthorsRobotham AC, Kelly JF
Journal
PubMed ID30894096
The detection of free sulfhydryls in proteins can reveal incomplete disulfide bond formation, indicate cysteine residues available for conjugation, and offer insights into protein stability and structure. Traditional spectroscopic methods of free sulfhydryl detection, such as Ellman's reagent, generally require a relatively large amount of sample, preventing their use for ... More
Regulating G protein-coupled receptors by topological inversion.
AuthorsDenard B, Han S, Kim J, Ross EM, Ye J
JournalElife
PubMed ID30835201
'G protein-coupled receptors (GPCRs) are a family of proteins containing seven transmembrane helices, with the N- and C-terminus of the protein located at the extracellular space and cytosol, respectively. Here, we report that ceramide or related sphingolipids might invert the topology of many GPCRs that contain a GXXXN motif in ... More
Transducin activates cGMP phosphodiesterase by trapping inhibitory ? subunit freed reversibly from the catalytic subunit in solution.
AuthorsAsano T, Kawamura S, Tachibanaki S
JournalSci Rep
PubMed ID31076603
'Activation of cGMP phosphodiesterase (PDE) by activated transducin a subunit (Ta*) is a necessary step to generate a light response in vertebrate photoreceptors. PDE in rods is a heterotetramer composed of two catalytic subunits, PDEa and PDEß, and two inhibitory PDE? subunits, each binding to PDEa or PDEß. Activation of ... More
Profilin and formin constitute a pacemaker system for robust actin filament growth.
AuthorsFunk J, Merino F, Venkova L, Heydenreich L, Kierfeld J, Vargas P, Raunser S, Piel M, Bieling P
JournalElife
PubMed ID31647411
'The actin cytoskeleton drives many essential biological processes, from cell morphogenesis to motility. Assembly of functional actin networks requires control over the speed at which actin filaments grow. How this can be achieved at the high and variable levels of soluble actin subunits found in cells is unclear. Here we ... More
Structural and Functional Characterization of the Bacterial Type III Secretion Export Apparatus.
AuthorsDietsche T, Tesfazgi Mebrhatu M, Brunner MJ, Abrusci P, Yan J, Franz-Wachtel M, Schärfe C, Zilkenat S, Grin I, Galán JE, Kohlbacher O, Lea S, Macek B, Marlovits TC, Robinson CV, Wagner S
JournalPLoS Pathog
PubMed ID27977800
'Bacterial type III protein secretion systems inject effector proteins into eukaryotic host cells in order to promote survival and colonization of Gram-negative pathogens and symbionts. Secretion across the bacterial cell envelope and injection into host cells is facilitated by a so-called injectisome. Its small hydrophobic export apparatus components SpaP and ... More
Sequential Translocation of Polypeptides across the Bacterial Outer Membrane through the Trimeric Autotransporter Pathway.
AuthorsSikdar R, Bernstein HD
JournalmBio
PubMed ID31641085
Trimeric autotransporter adhesins (TAAs) are a family of bacterial outer membrane (OM) proteins that are comprised of three identical subunits. Each subunit contains an N-terminal extracellular ("passenger") domain and a short C-terminal segment that contributes four ß strands to a single 12-stranded ß barrel. The mechanism by which the passenger ... More
Insights Into Enhanced Complement Activation by Structures of Properdin and Its Complex With the C-Terminal Domain of C3b.
Authorsvan den Bos RM, Pearce NM, Granneman J, Brondijk THC, Gros P
JournalFront Immunol
PubMed ID31552043
Properdin enhances complement-mediated opsonization of targeted cells and particles for immune clearance. Properdin occurs as dimers, trimers and tetramers in human plasma, which recognize C3b-deposited surfaces, promote formation, and prolong the lifetime of C3bBb-enzyme complexes that convert C3 into C3b, thereby enhancing the complement-amplification loop. Here, we report crystal structures ... More
Computationally Designed Peptides for Zika Virus Detection: An Incremental Construction Approach.
AuthorsMascini M, Dikici E, Robles Mañueco M, Perez-Erviti JA, Deo SK, Compagnone D, Wang J, Pingarrón JM, Daunert S
JournalBiomolecules
PubMed ID31533374
Herein, and in contrast to current production of anti-Zika virus antibodies, we propose a semi-combinatorial virtual strategy to select short peptides as biomimetic antibodies/binding agents for the detection of intact Zika virus (ZIKV) particles. The virtual approach was based on generating different docking cycles of tetra, penta, hexa, and heptapeptide ... More
Omomyc Reveals New Mechanisms To Inhibit the MYC Oncogene.
AuthorsDemma MJ, Mapelli C, Sun A, Bodea S, Ruprecht B, Javaid S, Wiswell D, Muise E, Chen S, Zelina J, Orvieto F, Santoprete A, Altezza S, Tucci F, Escandon E, Hall B, Ray K, Walji A, O'Neil J
JournalMol Cell Biol
PubMed ID31501275
The MYC oncogene is upregulated in human cancers by translocation, amplification, and mutation of cellular pathways that regulate Myc. Myc/Max heterodimers bind to E box sequences in the promoter regions of genes and activate transcription. The MYC inhibitor Omomyc can reduce the ability of MYC to bind specific box sequences ... More
A new class of recombinant human albumin with multiple surface thiols exhibits stable conjugation and enhanced FcRn binding and blood circulation.
AuthorsSchelde KK, Nicholls K, Dagnæs-Hansen F, Bunting K, Rawsthorne H, Andersen B, Finnis CJA, Williamson M, Cameron J, Howard KA
JournalJ Biol Chem
PubMed ID30602565
Human serum albumin is an endogenous ligand transport protein whose long circulatory half-life is facilitated by engagement with the human cellular recycling neonatal Fc receptor (hFcRn). The single free thiol located at Cys-34 in domain I of albumin has been exploited for monoconjugation of drugs. In this work, we increased ... More
New drugs for pharmacological extension of replicative life span in normal and progeroid cells.
AuthorsVatolin S, Radivoyevitch T, Maciejewski JP
JournalNPJ Aging Mech Dis
PubMed ID30675378
A high-throughput anti-aging drug screen was developed that simultaneously measures senescence-associated ß-galactosidase activity and proliferation. Applied to replicatively pre-aged fibroblasts, this screen yielded violuric acid (VA) and 1-naphthoquinone-2-monoxime (N2N1) as its top two hits. These lead compounds extended the replicative life spans of normal and progeroid human cells in a ... More
Structure-based Design of JOC-x, a Conjugatable Tumor Tight Junction Opener to Enhance Cancer Therapy.
AuthorsPitner R, Kim J, Davis-Bergthold J, Turner C, Vassal-Stermann E, Wang H, Adams J, Carter L, Ahlgren JA, Fender P, Lieber A, Carter D, Gray SA
JournalSci Rep
PubMed ID30992466
Disorganized intercellular junctions are critical for maintaining the integrity of solid epithelial tumors and prevent the infiltration of oncological therapies into the bulk of the malignancy. We have developed small, recombinant proteins which bind a critical junction protein, desmoglein 2, triggering the transient and specific opening of tumor tight junctions ... More
The MsrAB reducing pathway of Streptococcus gordonii is needed for oxidative stress tolerance, biofilm formation, and oral colonization in mice.
AuthorsJalal N, Lee SF
JournalPLoS One
PubMed ID32084213
The ability of Streptococcus gordonii to cope with oxidative stress is important for survival and persistence in dental plaque. In this study, we used mutational, phenotypic, and biochemical approaches to characterize the role of a methionine sulfoxide reductase (MsrAB) and proteins encoded by genes in the msrAB operon and an ... More