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Rosenfelder G, Chang JY, Braun DG. Sphingosine determination at the picomole level using dimethylaminoazobenzene sulphonyl chloride. JOURNAL OF CHROMATOGRAPHY 1983; 272:21-7. [PMID: 6404916 DOI: 10.1016/s0378-4347(00)86099-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A sensitive method (lower detection limit 5 picomoles) is proposed for the determination of sphingoid bases liberated from mammalian glycosphingolipids by acid hydrolysis. The azo dye 4-dimethylaminoazobenzene-4'-sulfonyl chloride reacts with the primary amino group of the sphingosine bases, forming a stable derivative. Excess reagent, which is degraded during the derivatization, and free amino sugars as common hydrolysis products of glycosphingolipids are completely separated by reversed-phase high-performance liquid chromatography. This method was applied to the determination of the glycosphingolipid content of mouse spleen and thymus.
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277
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Chang JY, Knecht R, Braun DG. Amino acid analysis in the picomole range by precolumn derivatization and high-performance liquid chromatography. Methods Enzymol 1983; 91:41-8. [PMID: 6406788 DOI: 10.1016/s0076-6879(83)91009-1] [Citation(s) in RCA: 126] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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278
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Chang JY. Manual micro-sequence analysis of polypeptides using dimethylaminoazobenzene isothiocyanate. Methods Enzymol 1983; 91:455-66. [PMID: 6406789 DOI: 10.1016/s0076-6879(83)91043-1] [Citation(s) in RCA: 131] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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279
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280
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Chang JY, Knecht R, Ball R, Alkan SS, Braun DG. A sensitive peptide mapping method. Identification of three amino acid substitutions within two anti-azobenzenearsonate monoclonal antibody light chains. EUROPEAN JOURNAL OF BIOCHEMISTRY 1982; 127:625-9. [PMID: 6816589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Peptide mixtures, precolumn-derivatized with dimethylaminoazobenzene isothiocyanate, have been separated by reversed-phase high-performance liquid chromatography to generate a dimethylaminoazobenzene thiocarbamoyl peptide map. The eluted peptide derivatives are detected in the visible region with a sensitivity of 2-5 pmol and can be collected for direct structural analysis. This technique was applied to compare the sequence homology of two immunoglobulin light chains which were derived from two anti-azobenzenearsonate monclonal antibodies, namely 10K44-7A1 and 10K26-12A1. The complete variable region sequences of 10K44-7A1 and 10K26-12A1 light chains were established based on the sequence analysis of tryptic peptides, intact light chains and reference sequences obtained previously [Siegelman M. and Capra, J.D. (1981) Proc. Natl Acad. Sci. USA, 78, 7679-7683]. Altogether, three amino acid substitutions have been detected within complementary determining regions 1 and 2, and framework region 3, all requiring only a single base change at the DNA level. This new technique provides detection limits and the feasibility of analysing peptides which are not obtainable with conventional techniques.
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281
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Herbst H, Chang JY, Aebersold R, Braun DG. Murine VK25 isotype sequence: monoclonal antibody 2S1.3 specific for the group A streptococcal polysaccharide. HOPPE-SEYLER'S ZEITSCHRIFT FUR PHYSIOLOGISCHE CHEMIE 1982; 363:1069-76. [PMID: 7141411 DOI: 10.1515/bchm2.1982.363.2.1069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Antibodies 2S1.3 and 2S1.1 are hybridoma derived gamma 3K murine immunoglobulins with specificity for N-acetylglucosamine beta 1 leads to 3-linked to L-rhamnose, the immunodeterminant of the streptococcal group A polysaccharide. The VL 2S1.3 amino acid sequence is the second complete one reported with this specificity, and it is the first fully determined VK25 structure. The VK regions of this and the previously described monoclonal anti-A-CHO antibody 7S34.1 are compared with 17 selected partial and complete murine VK regions, preferentially from anti-polysaccharide antibodies. Both VK 2S1.3 and 7S34.1 increase the variability of existing murine VK regions; however, they are, as anti-A-CHO antibodies, most homologous to each other sharing the so far unique residue argine 74. The amino acid sequence of the constant region of 2S1.3 light chain was also determined. It was found to be identical with that of MOPC21, but different from MOPC41 and MOPC70 in residue positions 127, 129, 163 and 166.
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282
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Chang JY, Knecht R, Braun DG. A complete separation of dimethylaminoazobenzenesulphonyl-amino acids. Amino acid analysis with low nanogram amounts of polypeptide with dimethylaminoazobenzenesulphonyl chloride. Biochem J 1982; 203:803-6. [PMID: 6810876 PMCID: PMC1158301 DOI: 10.1042/bj2030803] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A chromatographical system has been developed to give a complete baseline separation of all dimethylaminoazobenzenesulphonyl (DABS)-amino acids for high-sensitivity amino acid analysis [Chang, Knecht & Braun (1981) Biochem. J. 199, 547--556]. The system, which uses a Merck RP-18 column with phosphate buffer (12 mM, pH 6.5)/acetonitrile mixture, allows reliable analysis of DABS-amino acids at the 1--2 pmol level. The accuracy of this new system is demonstrated by the composition analysis of two immunoglobulin light chains (214 amino acid residues) with differences at only three amino acid residue positions.
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283
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Alpert NM, Chesler DA, Correia JA, Ackerman RH, Chang JY, Finklestein S, Davis SM, Brownell GL, Taveras JM. Estimation of the local statistical noise in emission computed tomography. IEEE TRANSACTIONS ON MEDICAL IMAGING 1982; 1:142-146. [PMID: 18238267 DOI: 10.1109/tmi.1982.4307561] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A simple modification of the filtered backprojection algorithm is presented for the computation of the local statistical noise in emission computed tomography. The technique is general in that any distribution of radioactivity may be accommodated. When applied to positron emission tomography, it is shown that the effects of photon absorption, random coincidences, radioactive decay, and detector nonuniformity may be included. Calculations have shown the effects of resolution, object size, and photon absorption on the statistical noise of disk-shaped emitters. Comparison of calculation and experiment show close agreement both in magnitude and spatial variation. Measurements of the noise level in tomograms of the brain obtained during continuous inhalation of 150-CO2 demonstrate that estimates of radioactivity concentration with a precision of a few percent are readily attainable.
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284
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Abstract
This paper describes a manual method for N-terminal sequence analysis of polypeptides at subnanomole sensitivity. The polypeptide is degraded stepwise by using the dimethylaminoazobenzene isothiocyanate/phenyl isothiocyanate double-coupling method, and the released dimethylaminoazobenzenethiohydantoins of amino acids were identified by reversed-phase high-pressure liquid chromatography. The dimethylaminoazobenzenethiohydantoins are coloured compounds and can be detected in the visible region with the sensitivity limit of 1 pmol (signal-to-baseline noise ratio 5). A high-pressure liquid-chromatographic method was developed for complete analysis of all amino acid dimethylaminoazobenzenethiohydantoin derivatives, including the by-products of serine and threonine. Thus, without use of an automatic sequenator or radioactive materials, it is possible to determine the complete sequence of peptides and N-terminal sequence of proteins with less than 1 nmol of material.
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285
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Chang JY, Knecht R, Braun DG. Amino acid analysis at the picomole level. Application to the C-terminal sequence analysis of polypeptides. Biochem J 1981; 199:547-55. [PMID: 6803769 PMCID: PMC1163409 DOI: 10.1042/bj1990547] [Citation(s) in RCA: 142] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Amino acids labelled with dimethylaminoazobenzenesulphonyl chloride can be separated by reversed-phase high-pressure liquid chromatography and detected in the visible region (436 nm). All 19 naturally occurring amino acids can be separated on a Zorbax ODS column by employing two different gradient systems consisting of an acetonitrile/aqueous buffer mixture. As little as 2--5 pmol of an individual dimethylaminoazobenzenesulphonyl-amino acid can be quantitatively analysed with reliability, and only 10--30 ng of the dimethylaminoazobenzenesulphonylated protein hydrolysate is needed for each complete amino acid analysis. This new technique is as sensitive as any of the current amino acid analysis methods involving ion-exchange separation plus fluorescence detection, and is technically much simpler. By the combination of this sensitive amino acid-analysing technique with carboxypeptidase, we have been able to determine the C-terminal sequence of polypeptides at the picomole level.
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286
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Chang JY. Isolation and characterization of polypeptide at the picomole level. Pre-column formation of peptide derivatives with dimethylaminoazobenzene isothiocyanate. Biochem J 1981; 199:537-45. [PMID: 6803768 PMCID: PMC1163408 DOI: 10.1042/bj1990537] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Polypeptides coupled with dimethylaminoazobenzene isothiocyanate through their amino groups to form dimethylaminoazobenzenethiocarbamoyl- (DABTC-)peptides can be separated by reversed-phase high-pressure liquid chromatography and detected in the visible region (436 nm). As little as 1 ng (2 pmol) of a DABTC-pentapeptide can be identified against a stable base-line with the signal-to-noise ratio of 10. The DABTC-peptides can also be recovered from the column, and their N-terminal amino acids (obtained by direct treatment with aqueous acid) and amino acid compositions and sequences can be all analysed at the picomole level. The power of this method is demonstrated by the complete separation and characterization of model peptides, peptide hormones and peptides derived from enzymic fragmentation of proteins. This new technique should provide a sensitive and efficient tool for peptide analysis at the nanogram level.
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287
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Chang JY, Gleich GJ, Atassi MZ. The role of the thiol group and the disulfide bond in the conformation and the IgE and IgG binding activities of ragweed allergen Ra3. Mol Immunol 1981; 18:991-7. [PMID: 6176852 DOI: 10.1016/0161-5890(81)90117-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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288
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Chang JY, Martin P, Bernasconi R, Braun DG. High-sensitivity amino acid analysis: measurement of amino acid neurotransmitter in mouse brain. FEBS Lett 1981; 132:117-20. [PMID: 6117477 DOI: 10.1016/0014-5793(81)80441-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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289
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Barr SI, Kottke BA, Chang JY, Mao SJ. Immunochemistry of human plasma apolipoprotein C-II as studied by radioimmunoassay. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 663:491-505. [PMID: 7213782 DOI: 10.1016/0005-2760(81)90177-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The immunoreactivity of human plasma apolipoprotein C-II was investigated using a specific radioimmunoassay. In whole plasma, the mean value quantitated was 2.21 +/- 0.415 mg/dl, while in delipidated plasma, a mean value of 3.84 +/- 1.186 mg/dl was obtained, suggesting that the antigenic sites of the apolipoprotein were not fully detected in unmodified plasma by our antibody preparation. Two detergents, Tween-20 and Triton X-100, were studied to determine if they could enhance the immunoreactivity of apolipoprotein C-II in whole plasma. At concentrations of 0.012-0.06%, Tween-20 markedly increased the immunoreactivity of whole plasma, but not of delipidated plasma, indicating that antigenic sites of plasma apolipoprotein C-II has been exposed by Tween-20. In contrast, Triton X-100 had no effect on the immunoreactivity of whole plasma apolipoprotein C-II. A radioimmunoassay conducted in the presence of 0.06% Tween-20, resulted in a mean value in whole plasma (3.39 +/- 1.11 mg/dl) that was not significantly different from that obtained when the assay was done on delipidated samples. The immunoreactivity of VLDL apolipoprotein C-II was also drastically enhanced following lipolysis by bovine milk lipoprotein lipase, supporting the hypothesis that antigenic sites are masked by the lipids. Finally, the mechanism responsible for the effect of Tween-20 on apolipoprotein C-II immunoreactivity was investigated. The results obtained from circular dichroism and ultracentrifugation suggest that the detergent may dissociate the apolipoprotein from lipoprotein particles, thus fully exposing the antigenic sites for reaction with antibodies.
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290
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Chang JY, Lehmann A, Wittmann-Liebold B. Analysis of dimethylaminoazobenzene-thiohydantoins of amino acid by high-pressure liquid chromatography. Anal Biochem 1980; 102:380-3. [PMID: 6775553 DOI: 10.1016/0003-2697(80)90171-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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291
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Chang JY. Amino-terminal analysis of polypeptide using dimethylaminoazobenzene isothiocyanate. Anal Biochem 1980; 102:384-92. [PMID: 6775554 DOI: 10.1016/0003-2697(80)90172-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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292
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Deng JS, Chang JY, Lü YC. Clinical significance and correlation of antinuclear antibodies and anti-DNA antibodies. J Dermatol 1979; 6:227-32. [PMID: 90686 DOI: 10.1111/j.1346-8138.1979.tb01905.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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293
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Chang JY. Manual solid phase sequence analysis of polypeptides using 4-N-N,-dimethylaminoazobenzene 4'-isothiocyanate. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 578:188-95. [PMID: 110357 DOI: 10.1016/0005-2795(79)90126-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A manual solid-phase method for sequence analysis of polypeptides is described. The immobilized polypeptide was subjected to stepwise degradation by Edman-type reagent, using the 4-N,N-dimethylaminoazobenzene 4'-isothiocyanate phenyllisothiocyanate double coupling method. The N-terminal amino acids were released (after conversion reaction) as 4-N,N-dimethylaminoazobenzene 4'-thiohydantoin (identified by thin layer chromatography) and phenylthiohydantoin derivatives. The method required 2--10 nmol polypeptide.
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294
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Chang JY. The destruction of serine and threonine thiohydantoins during the sequence determination of peptides by 4-N,N-dimethylaminoazobenzene 4'-isothiocyanate. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 578:175-87. [PMID: 36922 DOI: 10.1016/0005-2795(79)90125-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
1. A mechanism for the destruction of serine and threonine thiohydantoins during protein sequence analysis by the Edman-type degradation is proposed. The mechanism begins with the dehydration of serine and threonine side chains (at the cyclization stage) which occurs mainly in anhydrous acid solution. The dehydrated derivatives finally polymerize by way of the reactive methylene group (enamine) to form polymers with various molecular weights. In aqueous acid solution, the dehydrated thiohydantoins of serine and threonine undergo hydration (according to the Markovnikov rule) and ring fission, which leads to the irreversible breakdown of thiohydantoin ring. The serine derivative shows a much greater tendency to undergo these side-reactions than the threonine derivative. 2. In the presence of oxygen, the alkaline hydrolysis of amino acid thiohydantoins goes through an oxidation-deamination reaction at the C-N bond of the thiohydantoin ring and leads to the formation of thiourea derivative and keto acids. This reaction mechanism accounts for the low recoveries of amino acid obtained from the alkaline hydrolysis of amino acid thiohydantoins.
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295
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Chang JY, Deng JS, Lü YC. Significance of titers and patterns of antinuclear antibodies. TAIWAN YI XUE HUI ZA ZHI. JOURNAL OF THE FORMOSAN MEDICAL ASSOCIATION 1978; 77:852-8. [PMID: 370339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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296
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Chang JY. A novel Edman-type degradation: direct formation of the thiohydantion ring in alkaline solution by reaction of Edman-type reagents with N-monomethyl amino acids. FEBS Lett 1978; 91:63-8. [PMID: 27387 DOI: 10.1016/0014-5793(78)80018-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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297
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Chang JY, Creaser EH, Hughes GJ. Improved coupling of proteins to the support for solid phase protein sequencing. FEBS Lett 1977; 84:187-90. [PMID: 590520 DOI: 10.1016/0014-5793(77)81086-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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298
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Chang JY, Creaser EH, Hughes GJ. Separation of 4-N,N-dimethylaminoazobenzene-4'-thiohydantoins of amino acids by thin-layer chromatography on silica gel. J Chromatogr A 1977; 140:125-8. [PMID: 408371 DOI: 10.1016/s0021-9673(00)83613-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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299
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Chang JY. High-sensitivity sequence analysis of peptides and proteins by 4-NN-dimethylaminoazobenzene 4'-isothiocyanate. Biochem J 1977; 163:517-20. [PMID: 406900 PMCID: PMC1164732 DOI: 10.1042/bj1630517] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A manual high-sensitivity sequencing method is described, in which 4-NN-dimethylaminoazobenzene 4'-isothiocyanate is used for the stepwise degradation of amino acid residues from the peptides. The 4-NN-dimethylaminoazobenzene 4'-thiazolinones of amino acids that were released, after conversion into their thiohydantoin derivatives, were identified by t.l.c. on polyamide sheets. This new method is simple and sensitive, and requires only 2-10nmol of peptides or proteins for extended sequence analysis. The method was tested on the sequence analysis of a hexapeptide (Leu-Trp-Met-Arg-Phe-Ala), bradykinin, glucagon and native lysozyme. Results show that the proposed procedure is a sensitive method for the sequence determination of short peptides as well as for the partial sequence determination of intact proteins.
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300
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Chang JY, Creaser EH, Hughes GJ. A new approach for the solid phase sequence determination of proteins. FEBS Lett 1977; 78:147-50. [PMID: 326576 DOI: 10.1016/0014-5793(77)80293-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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