Elementary plant Biochemistry and Biotechnology (2+1)

Occurrence

 
• Proteins are found in all living cells. They form essential constituent of protoplasm, cell membrane and nuclear material. They may be present as simple proteins or complexes with lipids or nucleic acids. Proteins from different tissues such as muscle, bone, brain, blood and other biological fluids differ in composition and properties . In cereal and leguminous plants, seeds contain comparatively higher amounts of protein than stem, leaves and flowers. Tuber crops usually contain less amounts of protein in all parts. Enzymes are specialized proteins with catalytic activities and are present in all living organisms. Proteins serve as regulators of metabolic reactions, directly as components of enzymes and indirectly in the form of chemical messengers known as hormones as well as receptors for hormones. They regulate and integrate the numerous physiological and metabolic processes in the body. Proteins are the center of action in many biological processes