Lupus antibody bivalency is required to enhance prothrombin binding to phospholipid.
AuthorsField SL, Chesterman CN, Dai YP, Hogg PJ
JournalJ Immunol
PubMed ID11342631
'Lupus anticoagulants (LA) are a family of autoantibodies that are associated with in vitro anticoagulant activity but a strong predisposition to in vivo thrombosis. They are directed against plasma phospholipid-binding proteins including prothrombin. We have proposed that LA propagates coagulation in flowing blood by facilitating prothrombin interaction with the damaged ... More
Conformation coupled enzyme catalysis: single-molecule and transient kinetics investigation of dihydrofolate reductase.
'Ensemble kinetics and single-molecule fluorescence microscopy were used to study conformational transitions associated with enzyme catalysis by dihydrofolate reductase (DHFR). The active site loop of DHFR was labeled with a fluorescence quencher, QSY35, at amino acid position 17, and the fluorescent probe, Alexa555, at amino acid 37, by introducing cysteines ... More
Ligand binding regulates the directed movement of beta1 integrins on fibroblasts.
AuthorsFelsenfeld DP, Choquet D, Sheetz MP
JournalNature
PubMed ID8837776
'To enable cells to crawl, adhesion receptors such as integrins must bind to extracellular molecules and simultaneously interact with force-generating components of the cytoskeleton. We show here that the binding of extracellular ligand in living cells induces the attachment of beta1 integrins to the retrograde-moving cytoskeleton. Unliganded integrins are not ... More
Preparation of avidin conjugates.
AuthorsHaugland RP, Bhalgat MK
JournalMethods Mol Biol
PubMed ID9664375
Improved immunocytochemical detection of biotinylated probes with Neutralite avidin.
Authorsvan Roy N, Mangelschots K, Speleman F
JournalTrends Genet
PubMed ID8488564
Coupling of antibodies with biotin.
AuthorsHaugland RP, You WW
JournalMethods Mol Biol
PubMed ID9664374
Tumor-specific detection of an optically targeted antibody combined with a quencher-conjugated neutravidin
AuthorsOgawa M, Kosaka N, Choyke PL, Kobayashi H,
JournalBioconjug Chem
PubMed ID19072537
In vivo molecular cancer imaging with monoclonal antibodies has great potential not only for cancer detection, but also for cancer characterization. However, the prolonged retention of intravenously injected antibody in the blood causes low target tumor-to-background ratio (TBR). Avidin has been used as a ... More
Fluorescence nanoscopy in whole cells by asynchronous localization of photoswitching emitters.
AuthorsEgner A, Geisler C, von Middendorff C, Bock H, Wenzel D, Medda R, Andresen M, Stiel AC, Jakobs S, Eggeling C, Schönle A, Hell SW,
JournalBiophys J
PubMed ID17660318
We demonstrate nanoscale resolution in far-field fluorescence microscopy using reversible photoswitching and localization of individual fluorophores at comparatively fast recording speeds and from the interior of intact cells. These advancements have become possible by asynchronously recording the photon bursts of individual molecular switching cycles. We present images from the microtubular ... More
Single-molecule analysis of 1D diffusion and transcription elongation of T7 RNA polymerase along individual stretched DNA molecules.
AuthorsKim JH, Larson RG,
JournalNucleic Acids Res
PubMed ID17526520
Using total internal reflection fluorescence microscopy, we directly visualize in real-time, the 1D Brownian motion and transcription elongation of T7 RNA polymerase along aligned DNA molecules bound to substrates by molecular combing. We fluorescently label T7 RNA polymerase with antibodies and use flow to convect them orthogonally to the DNA ... More
Assessing the sensitivity of commercially available fluorophores to the intracellular environment.
AuthorsChen AK, Cheng Z, Behlke MA, Tsourkas A,
JournalAnal Chem
PubMed ID18700780
The use of fluorescence has become commonplace in the biological sciences, with many studies utilizing probes based on commercially available fluorophores to provide insight into cell function and behavior. As these imaging applications become more advanced, it becomes increasingly important to acquire accurate quantitative measurements of the fluorescence signal. Absolute ... More
Surface biopassivation of replicated poly(dimethylsiloxane) microfluidic channels and application to heterogeneous immunoreaction with on-chip fluorescence detection.
AuthorsLinder V, Verpoorte E, Thormann W, de Rooij NF, Sigrist H
JournalAnal Chem
PubMed ID11569807
Poly(dimethylsiloxane) (PDMS) appeared recently as a material of choice for rapid and accurate replication of polymer-based microfluidic networks. However, due to its hydrophobicity, the surface strongly interacts with apolar analytes or species containing apolar domains, resulting in significant uncontrolled adsorption on channel walls. This contribution describes the application and characterization ... More
Angiostatin formation involves disulfide bond reduction and proteolysis in kringle 5 of plasmin.
Plasmin is processed in the conditioned medium of HT1080 fibrosarcoma cells producing fragments with the domain structures of the angiogenesis inhibitor, angiostatin, and microplasmin. Angiostatin consists of kringle domains 1-4 and part of kringle 5, while microplasmin consists of the remainder of kringle 5 and the serine proteinase domain. Our ... More