Protein-Energy Malnutrition, Natural Peptides, and Enzymology

Comprehensive vocabulary flashcards covering Protein-Energy Malnutrition (PEM), Kwashiorkor, Marasmus, Natural Peptides, Enzymology, Enzyme Classification, Industrial Applications, Clinical Enzymology, and Diagnostic Biomarkers.

Underweight

Low weight-for-age in children; serves as a composite marker for both acute and chronic undernutrition.

Stunted

Low height-for-age resulting from chronic malnutrition, long-term insufficient nutrient intake, and frequent infections.

Wasted

Low weight-for-height representing acute malnutrition and dangerous thinness caused by recent rapid weight loss or failure to gain weight.

Protein-Energy Malnutrition (PEM)

A pathological state resulting from severe calorie or protein deficit, causing impaired protein synthesis for energy production.

Kwashiorkor

The wet or edematous form of severe PEM resulting primarily from severe protein deficiency relative to energy intake, characterized by generalized edema and preserved subcutaneous fat.

Marasmus

The dry form of severe PEM caused by total starvation, characterized by complete wasting of subcutaneous fat and muscle tissue without edema.

Depranocytosis

Hereditary blood disorder (Sickle-Cell Disease) caused by abnormal hemoglobin (HbS) that crystallizes when oxygen-depleted, distorting red blood cells into rigid sickle shapes.

Natural Peptides

Short chains of amino acids linked by peptide bonds that act as metabolic regulators, hormones, and neurotransmitters in cellular homeostasis.

Glutathione

A natural peptide present in most living cells that functions as a powerful antioxidant and stimulates tissue growth.

Bradykinin

A hypotensive vasodilator peptide that acts directly on vascular smooth muscle to regulate blood pressure.

Endothelin

A potent vasoconstrictor peptide structurally similar to certain snake venoms.

Melittin

A peptide component of honey bee venom used experimentally and clinically for rheumatism.

Biological Catalysts

Specialized organic proteins (enzymes) that accelerate cellular chemical reactions up to 107-fold without being consumed.

Enzymology

The scientific study of enzyme structure, kinetic mechanisms, and metabolic functions.

Apoenzyme

The inactive protein component of a conjugated enzyme that provides the 3D framework but requires a cofactor for catalytic activity.

Holoenzyme

The complete, active conjugated enzyme complex consisting of an apoenzyme bound to its cofactor.

Coenzymes

Non-protein organic helper molecules, frequently derived from B-vitamins, required for enzyme activity.

Metalloenzymes

Enzymes that contain tightly bound inorganic metal ion activators (such as $\text{Zn}^{2+}$, $\text{Fe}^{2+}$, or $\text{Mg}^{2+}$) necessary for catalytic activity.

Pellagra

A nutritional deficiency disease caused by a lack of Niacin (Vitamin B3), precursor to NAD+ and NADP+, characterized by Dermatitis, Diarrhea, and Dementia.

Beriberi

A deficiency condition caused by a lack of Thiamine (Vitamin B1), precursor to Thiamine Pyrophosphate (TPP).

Oxidoreductases

EC Class 1 enzymes that catalyze oxidation-reduction reactions between two substrates via electron or hydrogen transfer.

Transferases

EC Class 2 enzymes that catalyze the transfer of functional groups (such as amino or phosphate groups) between pairs of substrates.

Hydrolases

EC Class 3 enzymes that catalyze bond cleavage (ester, peptide, glycosyl) with the addition of water.

Lyases

EC Class 4 enzymes that catalyze the removal of groups without hydrolysis, forming double bonds.

Isomerases

EC Class 5 enzymes that catalyze the interconversion of optical, geometric, or positional isomers.

Ligases

EC Class 6 enzymes that catalyze the joining of two molecules coupled with ATP pyrophosphate cleavage.

Synthetases

ATP-dependent enzymes belonging strictly to EC Class 6 (Ligases) that catalyze biosynthetic joining reactions requiring direct ATP breakdown.

Synthases

ATP-independent enzymes belonging to classes other than Ligases that catalyze synthetic reactions without direct ATP breakdown.

Pepsin

A gastric protease derived from stomach mucosa of Sus scrofa that converts complex proteins to proteoses and peptones in acidic environments.

Erepsin

A digestive enzyme mixture found in human intestinal juice that converts proteoses and peptones into free amino acids.

Bromelains

Proteolytic enzymes derived from Ananas comosus used as meat tenderizers and anti-inflammatory aids for episiotomy repair.

Papain

A latex extract from Carica papaya used in contact lens cleaning, skin renewal whitening, meat tenderization, and chill-proofing beer.

Chymopapain

A plant enzyme injected into the nucleus pulposus to treat herniated lumbar intervertebral discs by lowering intradiscal pressure.

Streptokinase

A purified bacterial protein from Group C beta-hemolytic streptococci that converts plasminogen to active plasmin to dissolve fibrin blood clots.

Diastase

An amorphous powder from malt infusion capable of converting 50 times its own weight of potato starch into sugars.

Hyaluronidase

A mucolytic spreading factor that hydrolyzes hyaluronic acid to increase tissue permeability and speed subcutaneous absorption.

Collagenase

An enzyme derived from Clostridium histolyticum that cleaves native collagen fibers in necrotic tissue to debride severe ulcers and burns.

L-Asparaginase

An enzyme derived from Escherichia coli used to induce remission in pediatric acute lymphocytic leukemia (ALL) by starving tumor cells of L-asparagine.

Lock and Key Model

Fischer's binding model asserting that an enzyme's active site has a rigid, pre-formed structure complementary to its specific substrate.

Induced Fit Theory

Koshland's model stating that substrate binding induces dynamic conformational changes in the enzyme to correctly position catalytic groups.

Alanine Transaminase (ALT)

A liver transaminase enzyme whose elevation in serum serves as a specific biomarker for liver cell damage and hepatitis.

Creatine Phosphokinase (CPK)

An enzyme with distinct isoenzymes (CK-MM, CK-MB, CK-BB), where elevated CK-MB serves as a specific serum biomarker for acute myocardial infarction.