BOTANY WITH THE BASICS OF HYDROBOTANY (AQUATIC PLANTS OF UKRAINE) - B.Ye. Yakubenko - 2011

IV. PLANT ANATOMY AND MORPHOLOGY

Organic Compounds of Primary Origin

Proteins

Proteins are high-molecular-weight nitrogen-containing Organic compounds and Biopolymers composed of amino acid residues. The Elemental Composition of Amino Acids includes carbon, hydrogen, oxygen, nitrogen, and, in some cases, sulfur.

Currently, about 150 Amino acids are known, but only 20 of them are incorporated into protein molecules. Based on their chemical Structure, amino acids are classified into monoaminomonocarboxylic (Glycine, Alanine, valine, leucine, isoleucine, Serine, Threonine, Cysteine, cystine, Methionine, phenylalanine, Tyrosine); monoaminodicarboxylics (aspartic acid, glutamic acid); diaminomonocarboxylics (Arginine, Lysine); and heterocyclic (Proline, hydroxyproline, Tryptophan, Histidine).

Green plants are capable of synthesizing all amino acids, whereas Human and Animal organisms cannot synthesize Eight amino acids: tryptophan, phenylalanine, methionine, lysine, valine, threonine, isoleucine, and leucine. Since these amino acids are vital for life, they are referred to as essential or indispensable, and care is taken to ensure they are supplied to the body in adequate amounts.

A protein molecule has a strictly defined structure, the disruption of which leads to Protein Denaturation and the loss of its Properties and Functions. Based on their shape, protein molecules are divided into fibrillar (thread-like) and globular (spherical). The majority of plant proteins have a globular molecular shape.

Proteins are divided into simple proteins (proteins proper), whose molecules contain only amino acid residues, and Conjugated Proteins (proteids), which contain a non-protein moiety In addition to the protein part. In plants, simple proteins are represented by reserve and structural (supportive) proteins. Conjugated proteins are of particular importance in carrying out the vital Functions of the Cell.

Simple proteins include albumins (leucosin of wheat germ, legumelin of pea seeds), globulins of legume and oilseed seeds (phaseolin of beans, edestin of hemp, glycinin of soy, ricin of castor bean), prolamins—cereal seed proteins (gliadin of wheat, hordein of barley, avenin of oats), glutelins (glutenin of wheat, oryzenin of rice, corn glutelin), and proteinoids—Fibrillar Proteins (Silk Fibroin, Hair keratin, horn, hooves, tendons).

Depending on The Nature of the non-protein prosthetic group, conjugated proteins are classified into Lipoproteins (components of cytoplasmic membrane structures, particularly METABOLISM/14.html">Chloroplasts), Glycoproteins (Compounds of proteins with high-molecular-weight CARBOHYDRATES), and Nucleoproteins (compounds of proteins with Nucleic Acids).

In the plant Organism, proteins perform structural (membranes), catalytic (Enzymes), and storage functions.

Proteins are found in almost all food products, except for sugar and oil, as well as in feeds. Their biological value is determined by the content of Essential Amino Acids. Dietary proteins that contain all essential amino acids—which are predominantly animal proteins—are called complete proteins, in contrast to incomplete proteins, which are mainly of plant origin.

Amino acids are used primarily in medicine (preparations of cystine, methionine, histidine, and glutamic acid) and microbiology. They have a positive effect on immunochemical reactions.

Enzymes are specific protein substances that drive chemical transformations in organisms during metabolism. According to their composition, enzymes are divided into two groups: single-component (simple) enzymes, which consist of catalytic proteins, and two-component (complex) enzymes, which consist of a protein part (apoenzyme) and a non-protein part (coenzyme, or prosthetic group). Vitamins serve as Coenzymes for many enzymes.

The catalytic function within the enzyme molecule is performed by its specific region known as the Active Site.

Currently, over 1,000 different enzymes are known, which, based on the nature of their action, are divided into six classes: oxidoreductases, transferases, Hydrolases, lyases, isomerases, and ligases.

Enzymes found in feed components and foods of plant origin can cause their spoilage. For example, lipase, under conditions of elevated Temperature and humidity during the storage of flour, groats, and other high-fat products, can cause them to turn rancid.

The enzyme tyrosinase oxidizes The amino acid tyrosine into a dark-colored compound called melanin, which causes the dark color of rye bread and the darkening of pasta during the drying process. The browning of a cut apple or potato tuber is caused by polyphenol oxidase.

The enzyme lipoxygenase catalyzes the atmospheric oxygen Oxidation of Unsaturated Fatty acids within fat molecules, resulting in the rancidity of groats, flour, and other food products.

The enzyme pectase carries out the hydrolytic breakdown of pectic substances. It is abundant in Molds, alfalfa, potatoes, and citrus fruits.

Amylases obtained from dried sprouted grain (malt) break down starch and Glycogen (animal starch) to form dextrins, maltose, and glucose. The enzyme cellulase hydrolyzes Cellulose, producing the disaccharide cellobiose. This enzyme is characteristic of wood-decaying Fungi and Bacteria found in the gut of herbivorous animals.

Medical practice utilizes enzymes of animal origin (Pepsin, Trypsin, pancreatin, lidase), as well as those derived from dried cultures of mold fungi of the genus *Aspergillus* (amylorisin, glucavamorin, pectavamorin, xylavamorin). Microorganisms are used to produce amylases, dextrinases, maltases, cellulases, hemicellulases, pectinases, proteases, lipases, and Other Enzymes, which are utilized in animal husbandry to increase livestock weight gain and prevent diseases.