Separation of high-molecular mass RNAs by high-performance liquid chromatography on hydroxyapatite

1990 ◽  
Vol 515 ◽  
pp. 611-619 ◽  
Author(s):  
Shinichiro Hori ◽  
Sachiko Ohtani ◽  
Kenji Miyazaka ◽  
Toshihiro Ishikawa ◽  
Hitoshi Tanabe
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Molecular Mass ◽  
High Performance ◽  
High Molecular Mass

Angiotensin I–Converting Enzyme Inhibitory Activity of Peptides Derived from Egg White Proteins by Enzymatic Hydrolysis

2004 ◽  
Vol 67 (9) ◽  
pp. 1914-1920 ◽  
Author(s):  
M. MIGUEL ◽  
I. RECIO ◽  
J. A. GÓMEZ-RUIZ ◽  
M. RAMOS ◽  
R. LÓPEZ-FANDIÑO
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Molecular Mass ◽  
Inhibitory Activity ◽  
High Performance ◽  
Egg White ◽  
Reversed Phase ◽  
Converting Enzyme ◽  
Ace Inhibitory Activity ◽  
Ace Inhibitory

The hydrolysis of crude egg white with pepsin, trypsin, and chymotrypsin produced peptides with angiotensin-converting enzyme (ACE) inhibitory properties. These peptides were mainly derived from the proteolysis of ovalbumin. The most active hydrolysates were obtained after treatment with pepsin (50% inhibitory concentration [IC50], 55.3 μg/ml), with the fraction having a molecular mass lower than 3,000 Da giving the highest ACE inhibitory activity (IC50, 34.5 μg/ml). Nine subfractions were collected from the fraction with a molecular mass lower than 3,000 Da using semipreparative reversed-phase high-performance liquid chromatography. Considerable ACE inhibitory activity (IC50 < 40 μg/ml) was found in three of them. These subfractions were analyzed by reversed-phase high-performance liquid chromatography–tandem mass spectrometry, and 14 peptides were identified. These sequences were synthesized, and their ACE inhibitory activities were measured. Among the identified peptides, two novel sequences with potent ACE inhibitory activity were found. The amino acid sequences of these inhibitors were identified as Arg-Ala-Asp-His-Pro-Phe-Leu and Tyr-Ala-Glu-Glu-Arg-Tyr-Pro-Ile-Leu and showed IC50 values of 6.2 and 4.7 μM, respectively.

Does the B820 Subcomplex of the B880 Complex Retain Carotenoids?

1996 ◽  
Vol 51 (5-6) ◽  
pp. 309-318 ◽  
Author(s):  
Andrey Moskalenko ◽  
Olga Toropygina ◽  
Nina Kuznetsova
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Molecular Mass ◽  
Gel Electrophoresis ◽  
High Performance ◽  
Rhodospirillum Rubrum ◽  
Complex Structure ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
The Common

Abstract A study is reported on the modification of the B880-RC assembly of Chromatium minutissimum during octyl-β-D -glucopyranoside/dodecyl-β-D -maltoside/Deriphat polyacrylamide gel electrophoresis followed by electroelution with dodecyl-β-D-maltoside and high performance liquid chromatography with octyl-β-D-glucopyranoside according to the method developed by Kerfeld et al. (Biochim. Biophys. Acta 1185, 193-202 [1994a]) for isolation of the B820 subcomplexes of Chromatium purpuratum. The B880-RC assembly of Chromatium minutissimum isolated by electrophoresis was contaminated by the B 800-850 complex. It was further separated into four components, three of which were in agreement with the cited work: (i) colorless contaminations, (ii) the B880-RC assembly, (iii) the B 800-850 complex. In contrast with Kerfeld et al. (1994a), the fourth band was a band of free pigments (Bchl or Bchl-t-carotenoids) which had the same molecular mass as the B820 subcomplex of Chromatium purpuratum. For comparison, the B880-RC enriched fraction of Rhodospirillum rubrum modified by lyophilization in the presence of octyl-β-D-glucopyranoside with or w ithout carotenoids was separated by high performance liquid chromatography with octyl-β-D-glucopyranoside. The apparent molecular mass of the B820 subcomplex was 30 kD a for the sample without carotenoids and 245 kD a for that with carotenoids. The common principles of organization of the B880 complex, the interaction of the B 800- 850 complex with the B880-RC assembly, the participation of carotenoids in the stabilization of the B880 complex structure and the ability of different isolation steps to modify the structure of the B880 complex are discussed. It was concluded that there are other explanations for the presence of carotenoids in the B820 subcomplex. Hence, the question of whether the B820 subcomplex retains carotenoids remains open.

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