Globular proteins metabolic

DKPs are important metabolic intermediates and provoke the destruction of the secondary globular protein... 

A protein called keratin is insoluble in water but binds to other keratin molecules to form hard structures. Proteins like keratin are known as structural proteins or fibrous proteins. Keratin is the main component in hair and fingernails. A different protein called insulin is soluble in water and achieves a certain shape as an individual molecule. Proteins like insulin are known as globular proteins. Insulin in the bloodstream regulates glucose metabolism. 

Globular proteins/polypeptides are frequently employed in cells as functional proteins, responsible for respiration, metabolism and communication. However, the vast majority of proteins inside and indeed outside cells have structural, scaffolding functions. In these cases. 

Of all the functions of proteins, catalysis is probably the most important. In the absence of catalysis, most reactions in biological systems would take place far too slowly to provide products at an adequate pace for a metabolizing organism. The catalysts that serve this function in organisms are called enzymes. With the exception of some RNAs (ribozymes) that have catalytic activity (described in Sections 11.7 and 12.4), aU other enzymes are globular proteins (section 4.3). Enzymes are the most efficient catalysts known they can increase the rate of a reaction by a factor of up to 10 ° over uncatalyzed reactions. Non-enzymatic catalysts, in contrast, typically enhance the rate of reaction by factors of 102 to 104... 

Proteins are relatively complicated molecules made up from the 20 naturally occurring a-L-amino acids, which are linked to each other via peptide bonds. Fibrous proteins give mechanical strength to bones and muscles. Globular proteins such as antibodies and enzymes have specific functions in the immune system and in metabolism. The macromolecular chain of a protein is folded in a very specific way. This folding is essential for the protein s function and activity. The sequence of the amino acids is referred to as the primary structure of the protein. Parts of the amino acid chain form domains of regular structures such as a-helices and /3-pleated sheets. These make up the secondary structure of the protein. The whole three-dimensional shape of the amino acid chain including interactions between different secondary domains is referred as the tertiary structure. Some proteins consist of... 

Proteins are commonly classified into two main classes, viz fibrous and globular proteins. The former are the principal structural components of such materials as feathers, hair, nails and silk they consist of essentially linear polymers which are not dispersible in water. Globular proteins occur in materials such as egg-white, enzymes, metabolic intermediates and milk they are relatively compact cross-linked polymers and are dispersible in water. 

Muscle is a complex assembly of proteins embracing the metabolic capabilities characteristic of globular proteins and the structural capabilities of fibrous proteins and is thus well suited to perform the dual roles of converting chemical energy into mechanical energy and sustaining tension. Over 40 years ago a combination of electron microscopy and X-ray fibre... 

A group of proteins known as globular proteins have compact, spherical shapes because sections of the polypeptide chain fold over on top of each other dne to the various interactions between R groups. It is the globular proteins that carry ont the work of the cells functions such as synthesis, transport, and metabolism. 

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