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Cultivating a Three-dimensional Reconstructed Human Epidermis at a Large Scale
Published on: May 28, 2021
The polypeptide composition of epidermal prekeratin.
H P Baden1, L A Goldsmith, B Fleming
1Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA.
Biochimica Et Biophysica Acta
|December 17, 2009
Summary
Cow snout epidermis yields alpha-fibrous prekeratin, revealing three distinct polypeptide chains via electrophoresis. Analysis indicates prekeratin is a heterogeneous protein mixture, not a single homogenous entity.
Area of Science:
- Biochemistry
- Protein Chemistry
- Structural Biology
Background:
- Prekeratin, an alpha-fibrous protein, is a key component of the epidermis.
- Understanding the composition of prekeratin is crucial for elucidating epidermal structure and function.
Purpose of the Study:
- To isolate and characterize the polypeptide components of prekeratin from cow snout epidermis.
- To investigate the homogeneity and structural properties of prekeratin.
Main Methods:
- Isolation of prekeratin using citrate buffer.
- Analysis of polypeptide chains using acrylamide electrophoresis with sodium dodecyl sulfate (SDS-PAGE).
- Molecular weight determination and protein separation using chromatography (Sepharose 2B) and enzymatic digestion (TPCK-trypsin).
Main Results:
- Prekeratin comprises three polypeptide chains with molecular weights of approximately 47,000 (two components) and 58,000 (one component).
- Chromatography and electrophoresis confirmed the presence of distinct components.
- The 58,000 MW component exhibited an amino acid composition suggesting a non-helical structure and was more susceptible to trypsin digestion.
Conclusions:
- Cow snout prekeratin is not homogenous but a mixture of interacting polypeptide chains.
- At least one component, the 58,000 MW chain, possesses a non-helical structure, differing from the typical alpha-fibrous nature.
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