Structure and Function of Proteins

This difference m reactivity especially toward hydrolysis has an important result We 11 see m Chapter 27 that the structure and function of proteins are critical to life Itself The bonds mainly responsible for the structure of proteins are amide bonds which are about 100 times more stable to hydrolysis than ester bonds These amide bonds are stable enough to maintain the structural integrity of proteins m an aqueous environment but susceptible enough to hydrolysis to be broken when the occasion demands... 

Creighton, T. E., 1984. Proteins Structure and Molecular Properties. New York W. H. Freeman and Co. An advanced textbook on die. structure and function of proteins. 

John.son, L. N., and Barford, D., 1993. The effects of pho.sphorylation on the. structure and function of proteins. Annual Review of Biophysics and Biomolecular Structure 22 199-232. A review of protein pho.sphorylation and its role in regrdation of enzymatic activity, with particular empha.sis on glycogen pho.sphoryla.se. 

Introduction of heme residues and different artificial receptors in protein molecules in chemical modification of structures and functions of proteins by the cofactor reconstruction method 99Ef0539. 

RNA-editing is a posttranscriptional mechanism mediated by RNA editases, which results in a site-selective deamination of adenosine to inosine. This alters codons and splicing in nuclear transcripts and thereby alters the structure and function of proteins. 

Johnson LN, Barford D The effect of phosphorylation on the structure and function of proteins. Annu Rev Biophys Bio-mol Struct 1993 22 199. 

Section I deals with the structures and functions of proteins and enTymes, the workhorses of the body. Because almost all of the reactions in cells are catalyzed by enzymes, it is vital to understand the properties of enzymes before considering other topics. 

Cold Spring Harbor Symposia on Quantitative Biology. Vol. 36, Structure and Function of Proteins at the Three-Dimensional Level, 1972. 

Proteomics, on the other hand, is the application of molecular biology, biochemistry, and genetics to study the structures and functions of proteins expressed by cells. Unhke the genome, which is reasonably static, the proteome changes constantly in response to intra- and extracellular signals. As proteins are vital to our cells and the biological pathways, an in-depth understanding of proteomics would help to elucidate the processes of disease and to devise means to counteract errant cells and processes. 

The real value in the genome sequence is to find out the regions of the genome that encode proteins. Proteomics, the study of the structures and functions of proteins, further enhances our understanding of proteins and their functions, leading to insights on how they are affected in normal and disease conditions. Exhibit A2.3 shows some of the medical conditions due to genetic problems. 

During the past 25 years a considerable body of data has been accumulated, often to atomic resolution, on the structure and function of proteins. In contrast we know far less about the life cycle of these proteins—those processes which put a protein in the part of the cell in which it is to function and the cellular movements (if any) of this protein as it carries out its function. We know even less about those processes which eventually single out the protein for degradation. 

Site-specific incorporation of biophysical probes into proteins allows the structure and function of proteins to be probed with greater precision and accuracy using various biophysical means. Genetically encoded biophysical probes in the form of unnatural amino acids further extend the potential of these studies into live cells, the... 

The biosynthesis of tryptophan is outlined in Fig. 25-2. This amino acid not only assumes great importance in the structure and functioning of proteins but is converted into hormones, both in animals and plants, and into alkaloids in some plants. Some of the pathways are indicated in Figs. 25-11 and 25-12. 

Part 2, Protein Structure and Function, contains four chapters that relate to the structures and functions of proteins. In chapter 3, The Building Blocks of Proteins Amino Acids, Peptides, and Polypeptides, we discuss basic structural and chemical properties of amino acids, peptides and polypeptides. In chapter 4, The Three-Dimensional Structures of Proteins, we describe how and why polypeptide chains fold into long fibrous molecules in some cases, or into compact globular molecules in other cases. In chapter... 

We have discussed both target receptors and pharmacokinetics in this book. Protein manufacture is under direct genetic control, and two factors are of particular relevance here. First, the precise structure and function of protein macromolecules (receptors) targeted by a specific drug molecule will vary in different individuals. Since the structure and function of the protein are directly related to how the drug molecule will interact with that protein, individuals responses to the drug will vary. Second, there are genetic variations in metabolic enzymes (proteins) and hence metabolism. Both of these processes fall neatly into the domain of pharmacoproteomics (see Section 14.8). 

Sharma, S., Kumar, P., Betzel, Ch., and Singh, T. P. 2001. Structure and function of proteins involved in milk allergies. J Chromatogr B Biomed SciAppl 756(1-2) 183-187. 

Oligonucleotide-directed site-specific mutagenesis is a powerful technique for the study of proteins and has brought about great progress in research on the structure and function of proteins. This technique makes it possible in theory to obtain any mutant enzyme desired. One of the goals of such protein engineering is to make the proteins more stable. 

Long before molecular geneticists began tinkering with the structure and function of proteins and metabolic pathways, researchers were ma-... 

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