Record Details

Plastocyanin microheterogeneity in Scenedesmus acutus MT8

NOPR - NISCAIR Online Periodicals Repository

View Archive Info
 
 
Field Value
 
Title Plastocyanin microheterogeneity in Scenedesmus acutus MT8
 
Creator Dimitrov, Mitko I
Donchev, Anthony A
Toromanov, Georgi R
Getov, Vladimir I
Toncheva-Panova, Tonka G
 
Subject Plastocyanin
Microheterogeneity
Dimorphism
Isoelectric focusing
Chromatofocusing
 
Description 310-316
Two total plastocyanin (PC) fractions — loosely bound (lPC) and strongly bound (sPC) were extracted (84% and 16%,
respectively) from the homogenate of Scenedesmus acutus MT8. Two-fold isolation-purification procedure including DE-52
chromatography separated lPC into a smaller oxidized [lPC (II)] and a larger reduced [lPC(I)] fractions, in contrast to sPC,
where sPC(II) greatly dominated over sPC(I). Analytical isoelectric focusing (IEF) separated lPC(II) into two main fractions
only in the presence of 8 M urea, implying microheterogeneity. Preparative IEF in immobiline pH-gradient of 3.2-4.1
separated lPC(II) into two blue fractions – a more alkaline lPC'(II) and a more acidic lPC''(II), which were probably
stereoisomers. Their UV-Vis spectra exhibited rarely observed tryptophane (291.5 nm) and some differences at 270 and 287
nm. The exact molecular masses of apo-/holo-lPC (10131 Da/10194 Da) were determined by mass spectrometry. The
number of -SH groups was determined from the mass difference between alkylated with 4-vinylpyridine (4-VP) and nonalkylated
protein. Additionally, a simple procedure for simultaneous separation of both primary structure and stereoisomers
of PC was developed.
 
Date 2008-11-06T04:09:44Z
2008-11-06T04:09:44Z
2008-10
 
Type Article
 
Identifier 0301-1208
http://hdl.handle.net/123456789/2372
 
Language en_US
 
Publisher CSIR
 
Source IJBB Vol.45(5) [October 2008]