54aminoacid

54aminoacid is a term used to describe a molecule consisting of fifty-four amino acids in a single polypeptide chain. In protein science and bioinformatics, 54aa peptides serve as a simple, well-defined length class for studying folding, stability, and function. The term is often abbreviated as 54aa or a 54-residue peptide; in sequence data it may appear as sequences of letters with length 54.

Composition and structure depend on the specific sequence. The properties of a 54aa peptide can vary widely, with potential for alpha-helical, beta-sheet, or largely unstructured conformations. The estimated molecular weight is about 6 kilodaltons, and the isoelectric point is determined by the relative abundance of charged residues. Researchers use computational models to predict structure and stability based on sequence, but exact behavior is sequence-specific.

Production and analysis can be achieved through chemical synthesis or recombinant expression. Chemically synthesizing a 54aa peptide is common for defined sequences, while longer constructs can be expressed as fusion proteins and subsequently cleaved to yield the target 54aa segment. Purification typically involves high-performance liquid chromatography, and verification may employ mass spectrometry, circular dichroism, or nuclear magnetic resonance spectroscopy.

Applications and significance include using 54aa peptides as model systems for folding studies, stability testing, and sequence-structure relationships. They can serve as immunogenic epitopes, components in nanomaterial design, or building blocks in de novo peptide design and computational benchmarking.

Limitations include the fact that many 54aa sequences do not fold into stable, well-defined structures and may be prone to proteolysis. There is no single canonical 54aa peptide; many distinct sequences exist and each presents unique properties.

See also: peptide, protein length, amino acids, de novo protein design, peptide synthesis.