Definition of primary structure in English:

primary structure

noun

  • 1Biochemistry
    The characteristic sequence of amino acids forming a protein or polypeptide chain, considered as the most basic element of its structure.

    • ‘A protein's primary structure refers to the sequence of amino acids in the molecule.’
    • ‘The primary structure of peptides and proteins refers to the linear number and order of the amino acids present.’
    • ‘This, in turn, provides additional support for the hypothesis that life at high temperatures imposes unusual functional constraints on the primary structure of proteins.’
    • ‘The sequence of amino acids, called the primary structure of the enzyme, is determined by the gene coding for the enzyme.’
    • ‘Although various substitutions occur in primary structures of immunoglobulin light chains, no common amino acid has yet been identified which is unique to AL amyloidosis or other immunoglobulin-related diseases.’
  • 2Aviation
    The parts of an aircraft whose failure would seriously endanger safety.

    • ‘Fusion welded aluminum primary structures in airplanes are virtually nonexistent, because the high-strength alloys utilized have low weldability and low weld-joint efficiencies.’
    • ‘All of the airplane's primary structure was found at the accident site.’
    • ‘The certification of the 737 Composite Horizontal Stabilizer was the first large commercial aircraft primary structure in the world certified for commercial aircraft.’
    • ‘Primary structure for present transport aircraft is designed, based on average expected operational conditions and average fatigue test results, for 120,000 hrs.’