Protein biosynthetic system amino acids

As we have noted, the outcome of a virus infection is the synthesis of viral nucleic acid and viral protein coats. In effect, the virus takes over the biosynthetic machinery of the host and uses it for its own synthesis. A few enzymes needed for virus replication may be present in the virus particle and may be introduced into the cell during the infection process, but the host supplies everything else energy-generating system, ribosomes, amino-acid activating enzymes, transfer RNA (with a few exceptions), and all soluble factors. The virus genome codes for all new proteins. Such proteins would include the coat protein subunits (of which there are generally more than one kind) plus any new virus-specific enzymes. 

The contributions of Richard Block to the serum protein problem originated from the hypothesis of Kossel. From recent data on the amino acid composition of the proteins found in animal sera, a formulation is derived which reflects the properties of a continuous system of molecular species originating from a common biosynthetic pathway, as if from mixed polymers of monomeric peptides of lower molecular weight. Indirect evidence of this is found in the amino acid interrelationship, and direct evidence is limited to the isolation of peptides of common composition, whose primary structures are still under investigation. These findings suggest that undifferentiated proteins may be continuous systems rather than discrete molecular species. 

So what is a gamma-globulin molecule Could it not be a continuous system of molecular species, each slightly different from the next, wherein their properties would have a gaussian distribution The concept developed in this report shows how one could examine the properties of a system of closely related proteins in such a way that the molar ratio of certain amino acids, when related to mobility, exclude molecule species that do not belong to the same system. These parameters not only relate one molecular species to another, but possibly suggest their biosynthetic origin. 

In order to use fluorinated amino acids to study biological systems, they need to be synthesized and incorporated. Despite the challenges in both steps, there are several methods available. For instance, enantiomerically pure fluorinated amino acids may be prepared by asymmetric synthesis or by stereochemical resolution using enzymatic methods [48], Fluorinated amino acids can be introduced into proteins biosynthetically, or chemically by SPPS. Several reviews that detail the synthesis of enantiomerically pure fluorinated amino acids and incorporation methods into proteins are available [48-51],... 

In addition to these major processes, many other chemical events also occur. Mitochondria concentrate Ca ions and control the entrance and exit of Na, K, dicarboxylafes, amino acids, ADP, Pj and ATP, and many other substances. Thus, they exert regulatory functions both on catabolic and biosynthetic sequences. The glycine decarboxylase system (Fig. 15-20) is found in the mitochondrial matrix and is especially active in plant mitochondria (Fig. 23-37). Several cytochrome P450-dependent hydroxylation reactions, important to the biosynthesis and catabolism of sferoid hormones and to the metabolism of vitamin D, take place within mitochondria. Mitochondria make only a few of their ovm proteins but take in several hrmdred other proteins from the cytoplasm as they grow and multiply. 

The indole nucleus is embedded in many biological systems including the essential amino acid tryptophan, the neurotransmitter serotonin, and the mammalian hormone melatonin. Tryptophan is a structural constituent of many proteins as well as the biosynthetic precursor of serotonin, which in turn serves as the precursor of melatonin. Serotonin plays a critical role in neuronal cell formation and maintenance, sleep, cognition, appetite, and mood, while melatonin is a natural bioregulator that induces and maintains sleep [1,2]. 

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