Characterization of a cathepsin D protease from CHO cell-free medium and mitigation of its impact on the stability of a recombinant therapeutic protein

Metal/polysilicon investigations contribute to an understanding of issues relevant to the stability of electrical contacts in semiconductor devices. These investigations also contribute to an understanding of Si lateral solid-phase epitactic growth. Metals such as Au, Al and Ag form eutectics with Si. reactions in these metal/polysilicon systems lead to the formation of large-grain silicon. Of these systems, the Al/polysilicon system has been most extensively studied. In this study, the behavior upon thermal annealing of Au/polysilicon bilayers is investigated using cross-section transmission electron microscopy (XTEM). The unique feature of this system is that silicon grain-growth occurs at particularly low temperatures ∽300°C).Gold/polysilicon bilayers were fabricated on thermally oxidized single-crystal silicon substrates. Lowpressure chemical vapor deposition (LPCVD) at 620°C was used to obtain 100 to 400 nm polysilicon films. The surface of the polysilicon was cleaned with a buffered hydrofluoric acid solution. Gold was then thermally evaporated onto the samples.

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Preparation and Characterization of β-glucosidase Films for Stabilization and Handling in Dry Configurations

Current Pharmaceutical Biotechnology ◽

10.2174/1389201020666191202145351 ◽

2020 ◽

Vol 21 (8) ◽

pp. 741-747

Author(s):

Liguang Zhang ◽

Yanan Shen ◽

Wenjing Lu ◽

Lengqiu Guo ◽

Min Xiang ◽

...

Keyword(s):

Tensile Strength ◽

Protein Function ◽

Protein Stabilization ◽

Functional Protein ◽

Elongation At Break ◽

Gelatin Films ◽

The Stability ◽

And Function ◽

General Method

Background: Although the stability of proteins is of significance to maintain protein function for therapeutical applications, this remains a challenge. Herein, a general method of preserving protein stability and function was developed using gelatin films. Method: Enzymes immobilized onto films composed of gelatin and Ethylene Glycol (EG) were developed to study their ability to stabilize proteins. As a model functional protein, β-glucosidase was selected. The tensile properties, microstructure, and crystallization behavior of the gelatin films were assessed. Result: Our results indicated that film configurations can preserve the activity of β-glucosidase under rigorous conditions (75% relative humidity and 37°C for 47 days). In both control films and films containing 1.8 % β-glucosidase, tensile strength increased with increased EG content, whilst the elongation at break increased initially, then decreased over time. The presence of β-glucosidase had a negligible influence on tensile strength and elongation at break. Scanning electron-microscopy (SEM) revealed that with increasing EG content or decreasing enzyme concentrations, a denser microstructure was observed. Conclusion: In conclusion, the dry film is a promising candidate to maintain protein stabilization and handling. The configuration is convenient and cheap, and thus applicable to protein storage and transportation processes in the future.

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Chemical characterization of cathepsin D inhibitor from potatoes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19772279 ◽

1977 ◽

Vol 42 (7) ◽

pp. 2279-2286 ◽

Cited By ~ 2

Author(s):

L. Rupova ◽

H. Keilová ◽

V. Tomášek

Keyword(s):

Cathepsin D ◽

Chemical Characterization

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The Different Colors of mAbs in Solution

Antibodies ◽

10.3390/antib10020021 ◽

2021 ◽

Vol 10 (2) ◽

pp. 21

Author(s):

Alexandre Ambrogelly

Keyword(s):

Visual Inspection ◽

Quantitative Methods ◽

Geographical Area ◽

Therapeutic Protein ◽

Protein Solutions ◽

Protein Solution ◽

Critical Quality Attribute ◽

Recombinant Therapeutic Protein ◽

Protein Variants ◽

Antibody Solution

The color of a therapeutic monoclonal antibody solution is a critical quality attribute. Consistency of color is typically assessed at time of release and during stability studies against preset criteria for late stage clinical and commercial products. A therapeutic protein solution’s color may be determined by visual inspection or by more quantitative methods as per the different geographical area compendia. The nature and intensity of the color of a therapeutic protein solution is typically determined relative to calibrated standards. This review covers the analytical methodologies used for determining the color of a protein solution and presents an overview of protein variants and impurities known to contribute to colored recombinant therapeutic protein solutions.

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Characterization of the Domoic Acid Uptake Mechanism of the Mussel (Mytilus galloprovincialis) Digestive Gland

Toxins ◽

10.3390/toxins13070458 ◽

2021 ◽

Vol 13 (7) ◽

pp. 458

Author(s):

Juan Blanco ◽

Carmen Mariño ◽

Helena Martín ◽

Gonzalo Álvarez ◽

Araceli E. Rossignoli

Keyword(s):

Digestive Gland ◽

Domoic Acid ◽

Mytilus Galloprovincialis ◽

Metabolic Inhibitor ◽

Acid Uptake ◽

Free Medium ◽

Shellfish Poisoning ◽

Uptake Mechanism ◽

Amnesic Shellfish Poisoning

Cultures of the mussel Mytilus galloprovincialis are frequently affected by accumulation of the amnesic shellfish poisoning toxin domoic acid (DA). This species is characterized by a fast uptake and release of the toxin. In this work, the main characteristics of the uptake mechanism have been studied by incubation of digestive gland thin slices in media with different composition and DA concentration. DA uptake seems to follow Michaelis–Menten kinetics, with a very high estimated KM (1722 µg DA mL−1) and a Vmax of 71.9 µg DA g−1 h−1, which is similar to those found for other amino acids in invertebrates. Replacement of NaCl from the incubation media by Cl-choline (Na+-free medium) did not significantly reduce the uptake, but replacement by sorbitol (Na+-free and Cl−-depleted medium) did. A new experiment replacing all chlorides with their equivalent gluconates (Na+- and Cl−-free medium) showed an important reduction in the uptake that should be attributed to the absence of chloride, pointing to a Na+-independent, Cl− (or anion-) dependent transporter. In media with Na+ and Cl−, neither decreasing the pH nor adding cyanide (a metabolic inhibitor) had significant effect on DA uptake, suggesting that the transport mechanism is not H+- or ATP-dependent. In a chloride depleted medium, lowering pH or adding CN increased the uptake, suggesting that other anions could, at least partially, substitute chloride.

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Characterization of purified cathepsin D from malignant human breast tissue.

International Journal of Oncology ◽

10.3892/ijo.14.2.315 ◽

1999 ◽

Author(s):

S Bazel ◽

J A Alhadeff

Keyword(s):

Cathepsin D ◽

Breast Tissue ◽

Human Breast ◽

Human Breast Tissue

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Effect of pH and temperature on the infectivity of human coronavirus 229E

Canadian Journal of Microbiology ◽

10.1139/m89-160 ◽

1989 ◽

Vol 35 (10) ◽

pp. 972-974 ◽

Cited By ~ 40

Author(s):

Alain Lamarre ◽

Pierre J. Talbot

Keyword(s):

Incubation Period ◽

Storage Conditions ◽

Viral Infectivity ◽

Human Coronavirus ◽

Virus Growth ◽

The Stability ◽

And Storage ◽

Influence Of Ph ◽

Human Coronavirus 229E

The stability of human coronavirus 229E infectivity was maximum at pH 6.0 when incubated at either 4 or 33 °C. However, the influence of pH was more pronounced at 33 °C. Viral infectivity was completely lost after a 14-day incubation period at 22, 33, or 37 °C but remained relatively constant at 4 °C for the same length of time. Finally, the infectious titer did not show any significant reduction when subjected to 25 cycles of thawing and freezing. These studies will contribute to optimize virus growth and storage conditions, which will facilitate the molecular characterization of this important pathogen.Key words: coronavirus, pH, temperature, infectivity, human coronavirus.

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