Here is your Paragraph on the Chemical Nature of Lysosomes!

Chemically lysosomes are defined as “a body rich in acid hydrolase.” Acid phosphatases have been found in many cells of plant roots, fungi, and liver, kidney and endocrine glands.

Enzymes of Lysosomes. Lysosomes are a group of cytoplasmic organelles which contain intracellular proteases (cathepsins) and other hydrolytic enzymes. About 36 hydrolytic enzymes have been identified in lysosomes, including those that digest proteins (5), nucleic acids (4), polysaccharides (15), lipids (6), organic-linked sulphate (2), and organic-linked phosphate (4), although all do not occur in any one lysosome. Oxidative enzymes are completely absent in lysosomes unlike mitochondria.

In addition second type of lysosome, or ‘uricase particle’, is also recognized which contains the enzymes uricase, catalase, and D-amino acid oxidase. One important property of lysosomes is their stability in the living cell. This is because the enzymes are enclosed within membrane and the whole process of digestion is carried out with in the lysosome. Most lysosomal enzymes act in an acidic medium.

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The enzymes may be released from lysosomes by lysosome labilizers, such as action of blenders, freezing and thawing, ultraviolet radiation, vitamin K, detergents, protease and treatment with carbon tetrachloride, all of which disrupt the membrane.

Cortisone (a hormone), chloroquine (an antimalarial drug), and cholesterol, all of which strengthen the membrane, and are called lysosome stabilizers (De Duve, 1969). It has also been found that vitamin A tends to increase permeability, whereas vitamin E protects the lysosome membrane.

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