ISSN:0173-0835    

DOI:10.1002/elps.1150080102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

ISSN:0173-0835    

DOI:10.1002/elps.1150080103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractSteady state isoelectric focusing was treated as zero velocity isotachophoresis. From this standpoint, the author's theory of isotachophoresis was modified to deal with isoelectric focusing of protein molecules using carrier ampholytes, and mathematic simulations according to the modified theory were performed to calculate pH, voltag and concentration profiles in steady state isoelectric focusing. The results were in agreement with experiments with regard to resolving power for protein separation.

ISSN:0173-0835    

DOI:10.1002/elps.1150080104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractAn electrophoresis apparatus of the vertical slab gel type was designed to obtain a unit in which the number of spare parts and manual operations necessary for its assembly is significantly reduced as compared to the designs that are commonly used at present. The new apparatus is assembled in less than 60 s, and the gels are mouldedin situ.,i. e.without the use of a separate casting stand. With all electrode reservoirs placed within the base unit, the apparatus obviates the need for bulky external electrode reservoirs. The compact design is made possible by use of a permanently mounted porous plastic bridge that acts as a seal during moulding of the gel and as a conducting salt bridge during electrophoresis. The apparatus permits simultaneous running of two gels, and runs on single gels may be performed independently without filling the electrode reservoirs for the other gel.

ISSN:0173-0835    

DOI:10.1002/elps.1150080105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractProtein molecular weight standards labeled with different fluorochromes were tested for their usefulness in following the protein transfer from sodium dodecyl sulfate‐polyacrylamide gels to nitrocellulose and for electro‐elution of proteins from polyacrylamide gels. Dichlorotriazynylaminofluorescein labeled proteins appear to be useful for both purposes as they are stable, their detection sensitivity was high (about 10 ng of protein on nitrocellulose) and the coupling of the fluorochrome did not appreciably change the molecular weight of any protein examined. On the other hand, proteins labeled with tetramethylrhodamine isothiocyanate, or its heterocyclic derivative, were of limited usefulness as standards. Labeled proteins of molecular weight below 20 kDa formed diffuse bands on gels. Therefore, these particular fluorescent protein standards appear to be useful in following the elution from gels, or as references on nitrocellulose, only for proteins larger than 20–2

ISSN:0173-0835    

DOI:10.1002/elps.1150080106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA method has been developed for the two‐dimensional separation of proteins in a single thin‐layer gel, using sodium dodecyl sulfate‐polyacrylamide gel electrophoresis in the first dimension and isoelectric focusing in the second dimension. After two‐dimensional electrophoresis of concentrated culture supernatants fromStreptococcus mutans, the gels were directly stained with Coomassie Brilliant Blue R‐250 for protein and with periodic acid‐Schiff base reagent for glycoprotein. Glycosyl‐transferases were detected by incubating the gels in a sucrose‐containing buffer, either by visual observation of white spots of the product polysaccharides or by periodic acid‐Schiff staining of the products. All the procedures, including the staining steps, were done in a single gellayer covalently bound to a glass plate. The efficient removal of sodium dodecyl sulfate and renaturation of glycosyltransferases in the gel layers rendered this a simplified and rapid method for the relative molecular mass and isoelectric point determinations in the c

ISSN:0173-0835    

DOI:10.1002/elps.1150080107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractMicroscopical methods for sex determination of denatured samples in forensic laboratories are frequently unreliable. This paper describes the use of a recombinant DNA probe which hybridises specifically to a 2.47 kb repeat sequence of which 2000 copies are present on the Y chromosome. The technique enables rapid and reliable sex determinations of degraded DNA samples and produces results from blood stains greater than 4 years old in which only low molecular weight (<10 kb) DNA is present. Stains from less than 1 μL of blood or a single hair root is required for the test using dot blot hybridisations. Electrophoretic analyses revealed thatHaeIII restriction of DNA samples produced somatically stable patterns

ISSN:0173-0835    

DOI:10.1002/elps.1150080108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractMany highly polymorphic minisatellite loci can be detected simultaneously in the human genome by hybridisation to probes consisting of tandem repeats of the ‘core’ sequence. The resulting DNA fingerprints produced by Southern blot hybridisation are comprised of multiple hypervariable DNA fragments, show somatic and germline stability and are completely specific to an individual. DNA of high molecular weight can be isolated from blood and semen stains up to 4 years old. Sperm nuclei can be separated from vaginal debris and the sperm DNA examined in isolation, allowing the positive identification of rapists. Correspondingly, vaginal DNA can be isolated from extracts of penile swabs. DNA can also be isolated from extracts of buccal swabs. A blind trial involving 43 blood samples, 11 bloodstains and 11 semen stains has been successfully carried out. It is envisaged that genetic fingerprinting will shortly form an important part of casework procedure in forensic science laborator

ISSN:0173-0835    

DOI:10.1002/elps.1150080109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractHorizontal two‐dimensional (2‐D) electrophoresis with immobilized pH gradients (IPG) in the first dimension, described for soluble proteins inElectrophoresis1985, 6, 599–604, has been extended to an analysis of complex protein mixtures, such as leukemia cell proteins or bean proteins, in the presence of nonionic detergents. By optimizing the ratio of gel volumes for the first and second dimensional separation, and by decreasing the concentration of Nonidet P‐40 in the IPG gel, undistorted protein patterns in the 2‐D gel are obtained. Horizontal and vertical streaking are considerably diminished by optimized reswelling conditions of the dry IPG strips in presence of both urea and detergent. Resolution is improved and a reduced background is obtained when overcrowded gel areas are spread by flattening the pH gradient (in the first dimension) and the polyacrylamide gradient (in the second d

ISSN:0173-0835    

DOI:10.1002/elps.1150080110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractComparing the separation patterns achieved by hybrid isoelectric focusing in immobilized pH gradients of 1 and 3 meqv/pH/L buffering power, it is demonstrated that a significant proportion of sample protein is lost in gels with the higher buffering power. A buffering power of 1 meqv/pH/L was found to be the lowest acceptable limit for flat bed gel hybrid isoelectric focusing still ensuring adequate control of the immobilized pH gradient. Protein losses were manifested as diminished overall staining intensity, disappearance of individual zones in dilution series, tailing effects and residual material at the application site, all of the above effects being more pronounced for larger than smaller proteins. Adsorption of proteins to charged binding sites of the immobilized pH gradient offers a plausible explanation for the observed phenomena. The visible effects of adsorption could be reduced by the addition of carrier ampholytes, but not by urea or detergents like Triton X‐100, 3‐(3‐chol‐amidopropyl)‐dimethylammonio‐l‐propanesulfonate (CHAPS) or octyl β‐thio‐glucoside, indicating ionic interactions between the immobilized charged groups, carrier ampholytes and proteins. The adsorption phenomena may strongly affect the quantification of proteins in immobi

ISSN:0173-0835    

DOI:10.1002/elps.1150080111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY