scholarly journals Interaction of the small proteoglycan decorin with fibronectin. Involvement of the sequence NKISK of the core protein

1991 ◽  
Vol 280 (2) ◽  
pp. 411-414 ◽  
Author(s):  
G Schmidt ◽  
H Hausser ◽  
H Kresse
Keyword(s):  
Core Protein ◽  
Solid Phase ◽  
Repetitive Sequences ◽  
Central Position ◽  
Independent Manner ◽  
High Affinity ◽  
Kd Values ◽  
Solid Phase Assay ◽  
20 Nm ◽  
Small Proteoglycan

Decorin, an interstitial small proteoglycan, was shown to interact with fibronectin via its core protein. In a solid-phase assay, both high-affinity (KD values between 10 and 20 nM) and low-affinity (KD values between 110 and 130 nM) binding sites were found. The central position of decorin core protein is made up of several repeats containing NKISK in positions 85-89 and similar sequences in other repeats. The pentapeptide inhibited, albeit not completely, the high-affinity interaction between decorin and fibronectin in a specific charge-independent manner. Half-maximal inhibition occurred at a peptide concentration of 10 microM. Core-protein-derived peptides that had been produced by endoproteinase Lys-C digestion were not inhibitory, but endoproteinase Arg-C-generated peptides served as inhibitors of binding. These results suggest that NKISK as a component of repetitive sequences of decorin is involved in the interaction between the proteoglycan and fibronectin.

scholarly journals Binding of heparin and of the small proteoglycan decorin to the same endocytosis receptor proteins leads to different metabolic consequences.

1991 ◽  
Vol 114 (1) ◽  
pp. 45-52 ◽  
Author(s):  
H Hausser ◽  
H Kresse
Keyword(s):  
Cultured Cells ◽  
Dermatan Sulfate ◽  
Core Protein ◽  
Affinity Binding ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Receptor Proteins ◽  
High Affinity ◽  
Dermatan Sulfate Proteoglycan ◽  
Small Proteoglycan

Decorin, a small interstitial dermatan sulfate proteoglycan, is turned over in cultured cells of mesenchymal origin by receptor-mediated endocytosis followed by intralysosomal degradation. Two endosomal proteins of 51 and 26 kD have been implicated in the endocytotic process because of their interaction with decorin core protein. However, heparin and protein-free dermatan sulfate were able to inhibit endocytosis of decorin in a concentration-dependent manner. After Western blotting of endosomal proteins, there was competition for binding to the 51- and 26-kD proteins between heparin and decorin. In spite of its high-affinity binding, heparin was poorly cleared from the medium of cultured cells and then catabolized in lysosomes. In contrast to decorin, binding of heparin to the 51- and 26-kD proteins was insensitive to acidic pH, thus presumably preventing its dissociation from the receptor in the endosome. Recycling of heparin to the cell surface after internalization could indeed be demonstrated.

scholarly journals Influenza Viruses Display High-Affinity Binding to Human Polyglycosylceramides Represented on a Solid-Phase Assay Surface

Virology ◽  
1996 ◽  
Vol 223 (2) ◽  
pp. 413-416 ◽  
Author(s):  
Mikhail Matrosovich ◽  
Halina Miller-Podraza ◽  
Susann Teneberg ◽  
James Robertson ◽  
Karl-Anders Karlsson
Keyword(s):  
Solid Phase ◽  
Influenza Viruses ◽  
Affinity Binding ◽  
High Affinity Binding ◽  
High Affinity ◽  
Solid Phase Assay

scholarly journals Identification of a binding site on retinal transducin α for the phosphodiesterase inhibitory γ subunit

1994 ◽  
Vol 297 (1) ◽  
pp. 87-91 ◽  
Author(s):  
J Cunnick ◽  
C Twamley ◽  
I Udovichenko ◽  
K Gonzalez ◽  
D J Takemoto
Keyword(s):  
Binding Site ◽  
Solid Phase ◽  
Specific Binding ◽  
Dependent Manner ◽  
Gamma Subunit ◽  
High Affinity ◽  
Catalytic Function ◽  
Alpha Beta ◽  
Solid Phase Assay

Transducin alpha (T alpha) activates retinal rod cyclic GMP phosphodiesterase (PDE) by interacting with and removing the inhibitory PDE gamma subunit. A T alpha-PDE gamma complex can be isolated in vitro, and our previous work [Morrison, Rider and Takemoto (1987) FEBS Lett. 222, 266-270; Morrison, Cunnick, Oppert and Takemoto (1989) J. Biol. Chem. 264, 11671-11681] has identified a region of PDE gamma, residues 24-45, that binds to T alpha. The C-terminal region of PDE gamma is the site that interacts with PDE alpha/beta and inhibits catalytic function. The site on T alpha that binds to the PDE gamma 24-45 region has not been identified. Synthetic peptides (15-mers) which span the bovine T alpha sequence were tested for binding to purified recombinant PDE gamma using a solid-phase assay. The peptides were also tested for ability to activate a PDE complex. We have identified a region, residues 250-275 of T alpha, which shows a high affinity of PDE gamma and for the PDE gamma (24-45) binding peptide. The peptide did not bind to the C-terminal residues 50-87 of PDE gamma. Likewise, a region of T alpha, 1-25 did not exhibit high-affinity binding to PDE gamma or to the 24-45 PDE gamma peptide. Specific binding of the 250-275 peptide to PDE gamma was confirmed by its ability to compete with T alpha binding to PDE gamma, although a higher concentration was required (10x). The T alpha-(250-275) peptide activated a fully inhibited PDE alpha beta gamma 2 complex in a dose-dependent manner. These results suggest that a region on T alpha that recognizes the PDE gamma-binding site is found within residues 250-275 of T alpha.

Synthesis and Screening of A DNA-Encoded Library of Non-Peptidic Macrocycles

2020 ◽  
Author(s):  
Eric Koesema ◽  
Animesh Roy ◽  
Nicholas G. Paciaroni ◽  
Thomas Kodadek
Keyword(s):  
Solid Phase Synthesis ◽  
Solid Phase ◽  
Cell Permeability ◽  
Phase Synthesis ◽  
Protein Ligands ◽  
High Affinity ◽  
Scaffold Diversity

There is considerable interest in the development of libraries of non-peptidic macrocycles as a source of ligands for difficult targets. We report here the solid-phase synthesis of a DNA-encoded library of several hundred thousand thioether-linked macrocycles. The library was designed to be highly diverse with respect to backbone scaffold diversity and to minimize the number of amide N-H bonds, which compromise cell permeability. The utility of the library as a source of protein ligands is demonstrated through the isolation of compounds that bind streptavidin, a model target, with high affinity.

scholarly journals Design of PSMA ligands with modifications at the inhibitor part: an approach to reduce the salivary gland uptake of radiolabeled PSMA inhibitors?

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Veronika Barbara Felber ◽  
Manuel Amando Valentin ◽  
Hans-Jürgen Wester
Keyword(s):  
Salivary Gland ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis ◽  
In Vivo Studies ◽  
Tumor Xenograft ◽  
Tumor Uptake ◽  
Lncap Cells ◽  
High Affinity

Abstract Aim To investigate whether modifications of prostate-specific membrane antigen (PSMA)-targeted radiolabeled urea-based inhibitors could reduce salivary gland uptake and thus improve tumor-to-salivary gland ratios, several analogs of a high affinity PSMA ligand were synthesized and evaluated in in vitro and in vivo studies. Methods Binding motifs were synthesized ‘on-resin’ or, when not practicable, in solution. Peptide chain elongations were performed according to optimized standard protocols via solid-phase peptide synthesis. In vitro experiments were performed using PSMA+ LNCaP cells. In vivo studies as well as μSPECT/CT scans were conducted with male LNCaP tumor xenograft-bearing CB17-SCID mice. Results PSMA ligands with A) modifications within the central Zn2+-binding unit, B) proinhibitor motifs and C) substituents & bioisosteres of the P1′-γ-carboxylic acid were synthesized and evaluated. Modifications within the central Zn2+-binding unit of PSMA-10 (Glu-urea-Glu) provided three compounds. Thereof, only natLu-carbamate I (natLu-3) exhibited high affinity (IC50 = 7.1 ± 0.7 nM), but low tumor uptake (5.31 ± 0.94% ID/g, 1 h p.i. and 1.20 ± 0.55% ID/g, 24 h p.i.). All proinhibitor motif-based ligands (three in total) exhibited low binding affinities (> 1 μM), no notable internalization and very low tumor uptake (< 0.50% ID/g). In addition, four compounds with P1′-ɣ-carboxylate substituents were developed and evaluated. Thereof, only tetrazole derivative natLu-11 revealed high affinity (IC50 = 16.4 ± 3.8 nM), but also this inhibitor showed low tumor uptake (3.40 ± 0.63% ID/g, 1 h p.i. and 0.68 ± 0.16% ID/g, 24 h p.i.). Salivary gland uptake in mice remained at an equally low level for all compounds (between 0.02 ± 0.00% ID/g and 0.09 ± 0.03% ID/g), wherefore apparent tumor-to-submandibular gland and tumor-to-parotid gland ratios for the modified peptides were distinctly lower (factor 8–45) than for [177Lu]Lu-PSMA-10 at 24 h p.i. Conclusions The investigated compounds could not compete with the in vivo characteristics of the EuE-based PSMA inhibitor [177Lu]Lu-PSMA-10. Although two derivatives (3 and 11) were found to exhibit high affinities towards LNCaP cells, tumor uptake at 24 h p.i. was considerably low, while uptake in salivary glands remained unaffected. Optimization of the established animal model should be envisaged to enable a clear identification of PSMA-targeting radioligands with improved tumor-to-salivary gland ratios in future studies.

Solid-phase crystallization of ultra-thin amorphous Ge layers on insulators

2021 ◽  
Author(s):  
Ryo Oishi ◽  
Koji ASAKA ◽  
Bolotov Leonid ◽  
Noriyuki Uchida ◽  
Masashi Kurosawa ◽  
...  
Keyword(s):  
Grain Size ◽  
Grain Boundary ◽  
Barrier Height ◽  
Carrier Mobility ◽  
Solid Phase ◽  
Hole Mobility ◽  
Solid Phase Crystallization ◽  
Simple Method ◽  
20 Nm ◽  
Grain Boundary Barrier

Abstract A simple method to form ultra-thin (< 20 nm) semiconductor layers with a higher mobility on a 3D-structured insulating surface is required for next-generation nanoelectronics. We have investigated the solid-phase crystallization of amorphous Ge layers with thicknesses of 10−80 nm on insulators of SiO2 and Si3N4. We found that decreasing the Ge thickness reduces the grain size and increases the grain boundary barrier height, causing the carrier mobility degradation. We examined two methods, known effective to enhance the grain size in the thicker Ge (>100 nm). As a result, a relatively high Hall hole mobility (59 cm2/Vs) has been achieved with a 20-nm-thick polycrystalline Ge layer on Si3N4, which is the highest value among the previously reported works.

Analysis and Characterization of Solid and Liquid Organic Fertilizer from Hydrothermal Carbonization (HTC) of Chicken Feather and Blood Waste

2021 ◽  
Vol 21 (3) ◽  
pp. 651
Author(s):  
Agus Kuncaka ◽  
Rizky Ibnufaatih Arvianto ◽  
Almas Shafira Ramadhanty Bunga Latifa ◽  
Munawir Ramadhan Rambe ◽  
Adhitasari Suratman ◽  
...  
Keyword(s):  
Iron Content ◽  
Solid Phase ◽  
Organic Fertilizer ◽  
Liquid Product ◽  
Hydrothermal Carbonization ◽  
Mass Ratio ◽  
Solid Product ◽  
Chicken Waste ◽  
20 Nm

Conversion of feather and blood from chicken slaughterhouse waste for producing solid and liquid organic fertilizer excluding composting process with a variation of the mass ratio of feather and blood of a chicken has been conducted. The nitrogen, sulfur, and iron content in the solid and liquid product of the hydrothermal carbonization process were analyzed to identify and characterize the possibility of hydrolysate as a source of nitrogen, sulfur, and iron in soil fertilizer. Feather and blood of chicken waste were introduced to a hydrothermal carbonization reactor with the addition of limestone at a temperature range of 160–170 °C for the preparation of solid and liquid organic fertilizer. According to the FTIR interpretation, the solid product had functional groups such as NH, OH, CH sp3, SH, C=O, C=C, C–O–C, and C–H aromatic. The nitrogen, sulfur, and iron content of the optimal ratio in the solid phase were 4.67%, 1.63%, and 3694.56 ppm, while their contents in the liquid fertilizer were 3.76%, 1.80%, and 221.56 ppm, respectively. The vibration of 478 cm–1 is attributed to Fe–O paramagnetic (Fe2O3) confirmed by TEM images showed the diameter size less than 20 nm indicating the presence of superparamagnetic material.

scholarly journals Suppression of autocrine and paracrine functions of basic fibroblast growth factor by stable expression of perlecan antisense cDNA.

1997 ◽  
Vol 17 (4) ◽  
pp. 1938-1946 ◽  
Author(s):  
D Aviezer ◽  
R V Iozzo ◽  
D M Noonan ◽  
A Yayon
Keyword(s):  
Growth Factor ◽  
Fibroblast Growth Factor ◽  
Core Protein ◽  
Critical Role ◽  
Receptor Activation ◽  
Fibroblast Growth ◽  
Proliferating Cells ◽  
Transfected Cells ◽  
High Affinity

Heparan sulfate proteoglycans (HSPG) play a critical role in the formation of distinct fibroblast growth factor (FGF)-HS complexes, augmenting high-affinity binding and receptor activation. Perlecan, a secreted HSPG abundant in proliferating cells, is capable of inducing FGF-receptor interactions in vitro and angiogenesis in vivo. Stable and specific reduction of perlecan levels in mouse NIH 3T3 fibroblasts and human metastatic melanoma cells has been achieved by expression of antisense cDNA corresponding to the N-terminal and HS attachment domains of perlecan. Long-term perlecan downregulation is evidenced by reduced levels of perlecan mRNA and core protein as indicated by Northern blot analysis, immunoblots, and immunohistochemistry, using DNA probes and antibodies specific to mouse or human perlecan. The response of antisense perlecan-expressing cells to increasing concentrations of basic FGF (bFGF) is dramatically reduced in comparison to that in wild-type or vector-transfected cells, as measured by thymidine incorporation and rate of proliferation. Furthermore, receptor binding and affinity labeling of antisense perlecan-transfected cells with 125I-bFGF is markedly inhibited, indicating that eliminating perlecan expression results in reduced high-affinity bFGF binding. Both the binding and mitogenic response of antisense-perlecan-expressing clones to bFGF can be rescued by exogenous heparin or perlecan. These results support the notion that perlecan is a major accessory receptor for bFGF in mouse fibroblasts and human melanomas and point to the possible use of perlecan antisense constructs as specific modulators of bFGF-mediated responses.

114-P: Removing interference for solid phase assay: DTT treatment vs. heat inactivation

2009 ◽  
Vol 70 ◽  
pp. S69
Author(s):  
Patricia Willey ◽  
D. Phelan ◽  
G. Morris ◽  
T. Mohanakumar
Keyword(s):  
Solid Phase ◽  
Heat Inactivation ◽  
Solid Phase Assay
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