CRC critical reviews in biochemistry最新文献

{"title":"Twenty questions concerning the reaction cycle of the sarcoplasmic reticulum calcium pump.","authors":"C Tanford","doi":"10.3109/10409238409113603","DOIUrl":"https://doi.org/10.3109/10409238409113603","url":null,"abstract":"<p><p>The problem of \"mechanism\" for the calcium pump may be divided into three parts. (1) It is an enzyme catalyzing the hydrolysis of ATP. (2) At some stage of the reaction cycle it provides a pathway through the otherwise impermeable phospholipid bilayer. (3) The two properties are linked so as to provide exchange of free energy between the two substrates (ATP and Ca2+), without any exchange of matter. The third part is the most interesting, and the mechanistic problem it poses is common to all chemiosmotic free energy transducers. All three aspects of the mechanism are reviewed here, with special emphasis on the remaining experimental questions that need to be resolved. The review will show that even such fundamental questions as the exact stoichiometry of the catalyzed reaction have not yet received definitive answers.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"17 2","pages":"123-51"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409113603","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17164606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The complement components of the major histocompatibility locus.","authors":"R R Porter","doi":"10.3109/10409238409102804","DOIUrl":"https://doi.org/10.3109/10409238409102804","url":null,"abstract":"Polymorphism of complement components, recognized by differences in either their antigenic specificity or their electrophoretic mobility, together with studies of inherited deficiencies, has enabled many of their structural genes to be mapped. In humans, three genes (for C2, C4, and factor B) have been placed between HLA-D and HLA-B on chromosome 6 and in mice, C4 between H2-I and H2-D, chromosome 17. Structural studies show that these components have exceptional features. C2 and factor B which contain the proteolytic active site of the C3 and C5 convertases are of the classical and alternative pathway respectively and are similar in structure and function. Both are novel types of serine proteases. C4 (as C3) contains an intrachain thioester bond essential for hemolytic activity. Molecular genetic investigations are determining the relative positions of these genes, and their precise structure, and should clarify their relation to the inherited diseases which are associated with defects in this section of the human genome.","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"16 1","pages":"1-19"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409102804","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17294815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thin filament proteins and thin filament-linked regulation of vertebrate muscle contraction.","authors":"P C Leavis,&nbsp;J Gergely","doi":"10.3109/10409238409108717","DOIUrl":"https://doi.org/10.3109/10409238409108717","url":null,"abstract":"<p><p>Recent developments in the field of myofibrillar proteins will be reviewed. Consideration will be given to the proteins that participate in the contractile process itself as well as to those involved in Ca-dependent regulation of striated (skeletal and cardiac) and smooth muscle. The relation of protein structure to function will be emphasized and the relation of various physiologically and histochemically defined fiber types to the proteins found in them will be discussed.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"16 3","pages":"235-305"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409108717","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17443515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and properties of N-, O-, and S-phospho derivatives of amino acids, peptides, and proteins.","authors":"A W Frank","doi":"10.3109/10409238409102806","DOIUrl":"https://doi.org/10.3109/10409238409102806","url":null,"abstract":"<p><p>The literature on chemical (i.e., nonenzymic) phosphorylation of amino acids, peptides, and proteins is reviewed through 1982. The review covers synthetic methods, chemical reactions, and physical properties, with emphasis on the techniques used for separation and characterization of the products. Synthetic methods are classified by reagent rather than product, and are illustrated by experimental procedures for the most important methods. Chemical reactions are classified into four groups depending on whether the reaction site is the phospho group, the amino group, the carboxyl group, or in the case of serine the hydroxyl group. Physical data are given for all of the known N-, O-, and S-phospho derivatives of the amino acids, peptides, and proteins, within certain limitations, and are discussed in detail in the section on physical properties. Emphasis is given to the techniques used for separation of the products, such as chromatography and electrophoresis, and for characterization of the products, particularly spectroscopy. Medical and other uses of the products are mentioned.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"16 1","pages":"51-101"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409102806","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17385840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The stereochemistry of peptides containing alpha-aminoisobutyric acid.","authors":"B V Prasad,&nbsp;P Balaram","doi":"10.3109/10409238409108718","DOIUrl":"https://doi.org/10.3109/10409238409108718","url":null,"abstract":"<p><p>The introduction of alpha-aminoisobutyric acid (Aib) into peptides dramatically limits the range of accessible backbone conformations. The presence of two geminal methyl groups at C alpha sterically compels Aib residues to largely favor structures in the right- or left-handed 3(10)/alpha-helical regions (phi approximately +/- 60 +/- 20 degrees, psi approximately +/- 30 +/- 20 degrees) of the peptide conformational map. Aib residues occur extensively in microbial peptides which form transmembrane channels. This observation has stimulated considerable interest in the stereochemistry of Aib peptides. This review summarizes theoretical studies on the conformations of Aib residues and examines the available data on solid-state structures, derived from single crystal X-ray diffraction studies. Crystal structures of over three dozen Aib-containing peptides, ranging in length from 2 to 11 residues, have been reported so far which exemplify various types of beta-turns, consecutive beta-turns, and helical structures. Examples of nonhydrogen bonded and cyclic structures are also described. The crystallographic results compare well with structural studies in solution, establishing that Aib peptides can provide rigid structural models for the development of spectroscopic methods of peptide conformational analysis.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"16 4","pages":"307-48"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409108718","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17449226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inhibitors of the biosynthesis and processing of N-linked oligosaccharides.","authors":"A D Elbein","doi":"10.3109/10409238409102805","DOIUrl":"https://doi.org/10.3109/10409238409102805","url":null,"abstract":"<p><p>A number of glycoproteins have oligosaccharides linked to protein in a GlcNAc----asparagine bond. These oligosaccharides may be either of the complex, the high-mannose or the hybrid structure. Each type of oligosaccharides is initially biosynthesized via lipid-linked oligosaccharides to form a Glc3Man9GlcNAc2-pyrophosphoryl-dolichol and transfer of this oligosaccharide to protein. The oligosaccharide portion is then processed, first of all by removal of all three glucose residues to give a Man9GlcNAc2-protein. This structure may be the immediate precursor to the high-mannose structure or it may be further processed by the removal of a number of mannose residues. Initially four alpha 1,2-linked mannoses are removed to give a Man5 - GlcNAc2 -protein which is then lengthened by the addition of a GlcNAc residue. This new structure, the GlcNAc- Man5 - GlcNAc2 -protein, is the substrate for mannosidase II which removes the alpha 1,3- and alpha 1,6-linked mannoses . Then the other sugars, GlcNAc, galactose, and sialic acid, are added sequentially to give the complex types of glycoproteins. A number of inhibitors have been identified that interfere with glycoprotein biosynthesis, processing, or transport. Some of these inhibitors have been valuable tools to study the reaction pathways while others have been extremely useful for examining the role of carbohydrate in glycoprotein function. For example, tunicamycin and its analogs prevent protein glycosylation by inhibiting the first step in the lipid-linked pathway, i.e., the formation of Glc NAc-pyrophosphoryl-dolichol. These antibiotics have been widely used in a number of functional studies. Another antibiotic that inhibits the lipid-linked saccharide pathway is amphomycin, which blocks the formation of dolichyl-phosphoryl-mannose. In vitro, this antibiotic gives rise to a Man5GlcNAc2 -pyrophosphoryl-dolichol from GDP-[14C]mannose, indicating that the first five mannose residues come directly from GDP-mannose rather than from dolichyl-phosphoryl-mannose. Other antibodies that have been shown to act at the lipid-level are diumycin , tsushimycin , tridecaptin, and flavomycin. In addition to these types of compounds, a number of sugar analogs such as 2-deoxyglucose, fluoroglucose , glucosamine, etc. have been utilized in some interesting experiments. Several compounds have been shown to inhibit glycoprotein processing. One of these, the alkaloid swainsonine , inhibits mannosidase II that removes alpha-1,3 and alpha-1,6 mannose residues from the GlcNAc- Man5GlcNAc2 -peptide. Thus, in cultured cells or in enveloped viruses, swainsonine causes the formation of a hybrid structure.(ABSTRACT TRUNCATED AT 400 WORDS)</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"16 1","pages":"21-49"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409102805","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17294816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The synthesis and biology of fluorinated prostacyclins.","authors":"W E Barnette","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Fluorination has been used extensively in the steroid field to alter and/or enhance activity and to increase chemical or biological stability taking advantage of the similarity in size between hydrogen and fluorine and its strong electronegativity. Thus, it is not surprising to find that the same principle has been applied to prostaglandins, more specifically prostacyclin. The specific activity and high instability of Prostacyclin make it an ideal candidate for similar fluorination techniques. The design and preparation of fluorinated analogs with the aim of improving the chemical and metabolic stability of this important molecule will be discussed.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"15 3","pages":"201-35"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17429558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Introduction of purified genes into mammalian cells.","authors":"R Kucherlapati,&nbsp;A I Skoultchi","doi":"10.3109/10409238409108719","DOIUrl":"https://doi.org/10.3109/10409238409108719","url":null,"abstract":"<p><p>There are a number of methods to introduce genes into mammalian cells. These include cell hybridization, chromosome-mediated and DNA-mediated gene transfer. DNA-mediated transfer can be achieved by direct microinjection methods or by indirect methods. The DNA enters the nucleus and is expressed in a high proportion of cells transiently. The DNA then becomes integrated into host cell DNA at random sites resulting in more stably expressing transformants. A number of genes for which selection systems exist can be introduced into mammalian cells. Nonselectable genes can also be introduced into cells by either ligating them to a selectable gene or by mixing them with carrier DNA and a selectable gene. If an amplifiable gene sequence is introduced into cells, it and other genes in its proximity can be coamplified. Amplification of the genes can also be achieved by the use of appropriate viral vectors and recipient cells. The foreign genes are expressed in the recipient cells if they contain the appropriate recognition signals for initiation and termination of transcription. Transfection systems are thus permitting identification of DNA sequences which have a regulatory role in gene expression. The identification of transcriptional signal sequences has formed the basis for construction of appropriate molecules which would permit expression of genes which cannot normally be expressed in mammalian cells (e.g., bacterial genes). The foreign genes are not only expressed in the recipient cells but they can also be subject to regulation in the appropriate environment. This observation is paving the way for identification of regulatory sequences. The foreign DNA sequences integrated into the host genome can be recovered by a variety of methods. Such methods permit isolation of genes which code for a selectable gene product.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"16 4","pages":"349-79"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409108719","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17161311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Processing of tRNA in prokaryotes and eukaryotes.","authors":"M P Deutscher","doi":"10.3109/10409238409110269","DOIUrl":"https://doi.org/10.3109/10409238409110269","url":null,"abstract":"<p><p>Considerable progress has been made in defining the steps in the conversion of a tRNA precursor to a mature tRNA. These steps, which differ in different systems, include removal of precursor-specific residues from the 5' and 3' termini of the initial transcript, addition of the 3'-C-C-A terminus, splicing of intervening sequences, and modification of nucleotide residues. Despite these advances in defining the \"pathways\" of tRNA processing, relatively little is known about most of the enzymes actually involved in these processing steps. In this article I describe the sequence of reactions needed to convert the initial tRNA transcript to a functional, mature tRNA, and discuss the specificity and properties of enzymes known to be involved in this process. In addition, I speculate on the expected specificities of other enzymes involved in tRNA processing which have not yet been identified, and on the structural organization of the processing machinery.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"17 1","pages":"45-71"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409110269","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17161314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dye-ligand affinity chromatography: the interaction of Cibacron Blue F3GA with proteins and enzymes.","authors":"S Subramanian","doi":"10.3109/10409238409102302","DOIUrl":"https://doi.org/10.3109/10409238409102302","url":null,"abstract":"<p><p>The dye Cibacron Blue F3GA has a high affinity for many proteins and enzymes. It has therefore been attached to various solid supports such as Sephadex, Sepharose, polyacrylamide, and the like. In the immobilized form the dye has rapidly been exploited as an affinity chromatographic medium to separate and purify a variety of proteins including dehydrogenases, kinases, serum albumin, interferons, several plasma proteins, and a host of other proteins. Such a diversity shown by the blue dye in binding several unrelated classes of proteins has generated considerable work in terms of studies of the chromophore itself and also the immobilized ligand. As a prelude to realizing the full potential of the immobilized Cibacron Blue F3GA, an understanding of the basic interactions of the dye with its surroundings must be gained. It has been recognized that the dye is capable of hydrophobic and/or electrostatic interactions at the instance of the ambient conditions. The study of interactions of the dye with salts, solvents, and other small molecules indicates the nature of the interactions of the dye with different kinds of groups at the interacting sites of proteins. The review will cover such interactions of the dye with the proteins, the interactions of the proteins with the immobilized ligand, and the media used to elute the bound protein in several cases, and thus consolidate the available information on such studies into a cogent and comprehensive explanation.</p>","PeriodicalId":75744,"journal":{"name":"CRC critical reviews in biochemistry","volume":"16 2","pages":"169-205"},"PeriodicalIF":0.0,"publicationDate":"1984-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3109/10409238409102302","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"17267883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}