#protein

• Albuminuria — A pathological condition manifested by the abnormal presence or excretion of albumin in the urine, serving as a major clinical indicator of damage to or increased permeability of the kidneys' filtering membrane (nephrotic syndrome, diabetic, or hypertensive nephropathy).
• Albumose — A term utilized in older biochemical nomenclature to designate proteoses, a group of soluble macromolecular products resulting from the partial hydrolysis or enzymatic digestion of albumins, which do not coagulate with heat and precipitate under the action of ammonium sulfate.
• Albumosuria — A pathological condition manifested by the presence or excretion of albumoses (proteoses) in the urine; a term used in older clinical nomenclature to describe a particular form of proteinuria, historically associated with conditions such as multiple myeloma (known as Bence-Jones albumosuria) or severe infections.
• Egg white — A fluid, viscous, transparent organic substance rich in proteins (especially ovalbumin) that surrounds the yolk of a bird or reptile egg. Upon thermal treatment or mechanical whipping, it becomes opaque, white, and solid, serving an essential biological role in protecting and nourishing the embryo, as well as a major structural use in culinary arts and confectionery.
• Aldolase — An enzyme belonging to the lyase class that catalyzes the reversible cleavage of fructose-1,6-bisphosphate into two triose phosphates (glyceraldehyde-3-phosphate and dihydroxyacetone phosphate), a core step in the glycolytic pathway. Clinical measurements of its serum levels are utilized to diagnose acute muscle or hepatic disorders.
• Aleurone — An archaic form or morphological variant derived for aleurone, designating the totality of reserve protein granules stored in the peripheral layer of the endosperm in cereal seeds. Adjectivally, the term describes a plant structure or seminal tissue with a high concentration of nitrogenous substances and crystalline protein inclusions, playing an essential role in embryo nutrition during germination.
• Aleuron — A reserve protein substance, with an amorphous or crystalloid granular structure, deposited in the cells of the outermost layer of the endosperm in plant seeds (particularly in grasses). It represents a biochemical complex rich in amino acids, phosphates, and enzymes, playing a vital structural role in nourishing and metabolically supporting the embryo during the early stages of germination.
• Aleurone — The granular protein formation localized in the cells of the outermost endosperm layer within cereal seeds and other natural or genetically modified plants. It represents a biochemical aggregate stored as crystalloids and globuloids in dehydrated vacuoles, with the fundamental function of providing amino acids, minerals, and hydrolytic enzymes required to nourish the embryo during initial germination stages.
• Aleuronat — A dietary food preparation in the form of coarse flour or powder, industrially manufactured by artificially enriching cereal flour with proteins extracted from the aleurone layer (gluten and phytoglobulins). It is widely used in specialized nutrition and in manufacturing hypoglycemic products intended for patients suffering from diabetes or metabolic disorders, due to its massive nitrogen supply and extremely low carbohydrate content.
• Aleuronic — Pertaining to aleurone, belonging to aleurone, or containing a large amount of reserve protein granules. In structural plant biology, the term describes tissues, cells, or seminal layers defined by intense enzymatic activity and the presence of nitrogenous crystalloid inclusions involved in plant germinative metabolism.
• Alexin — A historical term used in early immunology, introduced by Hans Buchner and popularized by Jules Bordet, to designate the complement system; a thermolabile protein substance present in normal blood serum capable of destroying bacteria and other foreign cells in cooperation with specific antibodies (sensitizers). In modern biochemistry, its action is studied as an integral part of the innate non-specific immune response of cell lysis.
• Allotypic — Pertaining to or relating to an allotype, or presenting a structural variation specific to a subset of individuals within the same species. In immunogenetics, it describes antigenic determinants or polymorphic sequence modifications of serum proteins; in psychology, it can refer to behaviors or traits externally adapted or determined by complementary factors.
• Amide — An organic compound functionally derived from a carboxylic acid where the hydroxyl group (-OH) has been replaced by an amino group (-NH2, -NHR, or -NR2), having the general structural formula R-CO-NR2. Amides are fundamental in nature and industry, forming the peptide bonds that link amino acids into proteins and synthetic polymers like nylon, characterized by high chemical stability due to the conjugation of electrons from the nitrogen atom with the carbonyl group.
• Amyloid — An insoluble protein macromolecular aggregate with a pathological fibrillar structure folded into beta-sheets, which abnormally deposits in the intercellular spaces of various organs and tissues. Although its historical name suggests a resemblance to starch due to its specific staining reaction with iodine, amyloid is composed of conformationally altered proteins and is directly responsible for the onset and progression of amyloidosis and severe neurodegenerative disorders, such as Alzheimer's disease.
• Amyloid — The feminine form of the adjective 'amiloid', used to describe a substance, degeneration, senile plaque, or organic infiltration that exhibits the structural, physicochemical, or tinctorial characteristics of amyloid. It is frequently encountered in established medical phrases such as 'amyloid substance' or 'amyloid plaque', indicating the presence of pathological protein polymers.
• Amyloidosis — A systemic or localized metabolic and progressive disorder characterized by the abnormal deposition of amyloid (faultily folded insoluble proteins in beta-sheets) within the extracellular spaces of vital organs, such as the kidneys, heart, liver, or nervous system. This structural accumulation causes progressive atrophy of the cellular parenchyma and severe dysfunctions or organ failures, classified into primary, secondary, hereditary, or aging-associated forms.
• Aminoacetic — Derived from acetic acid by substituting a hydrogen atom in the methyl group with an amino group. The term is used almost exclusively in the phrase 'aminoacetic acid', the systematic name for glycine (or glycocoll), the simplest natural aliphatic amino acid, a basic structural constituent of animal proteins, used in medicine as a nutrient and in industry as a buffer solution.
• Amino acid — An organic compound with a mixed function, containing in its molecule one or more amino groups (-NH2) and carboxyl groups (-COOH). These structural compounds are the fundamental building blocks of proteins, classified into essential (which cannot be synthesized by the organism and must be provided by diet) and non-essential, playing a crucial role in cellular metabolism, enzyme synthesis, and nerve impulse transmission.
• Aminopeptidase — An enzyme of the exopeptidase class that catalyzes the specific hydrolysis of peptide bonds at the free N-terminal end of a polypeptide chain, successively releasing terminal amino acids. This biocatalyst plays an essential structural role in the final phases of protein digestion within the intestinal mucosa, as well as in intracellular protein degradation and recycling processes.
• Anabolic — Stimulating or pertaining to anabolism; a metabolic process of biosynthesis through which the organism transforms simple nutrients into complex cellular compounds (proteins, muscle tissue), consuming energy. As a neuter noun (in plural, anabolic steroids), it designates synthetic substances or hormones used medically for recovery or, improperly in sports, for fast muscle mass gain.