100aminoacid

100aminoacid refers to a polypeptide chain composed of 100 amino acid residues. In proteins, this length commonly corresponds to a single structural domain, a unit capable of folding independently into a stable three-dimensional shape. The average molecular weight of an amino acid residue is about 110 daltons, so a 100-residue peptide has an approximate mass near 11 kilodaltons, though the exact value varies with composition.

Structure and properties on the 100-amino-acid scale can vary widely. Such polypeptides can adopt diverse folds, including all-α, all-β, or mixed α/β architectures. The stability of a 100-aa protein depends on factors like hydrophobic core packing, disulfide bonds, and solvent conditions. Shorter or highly charged sequences may be more flexible and prone to aggregation, while well-designed or naturally occurring 100-aa domains can be remarkably stable and compact.

Synthesis, expression, and analysis: 100-aa polypeptides can be produced chemically by solid-phase synthesis or biologically via recombinant expression. Challenges include aggregation, proteolytic degradation, and solubility limits. Purification often employs standard chromatographic methods, and verification uses mass spectrometry. Structural characterization employs circular dichroism for secondary structure, and techniques such as NMR or X-ray crystallography for detailed three-dimensional information.

Applications and relevance: 100-aa proteins are common targets in folding studies, protein design, and engineering projects. They serve as model systems for understanding domain formation, stability, and function, and can be used to create scaffoldings, binders, or small therapeutic or diagnostic motifs.