R-phycocyanin (RPC) of Porphyra haitanensis (T. J. Chang et B. F. Zheng )' was chromatographed on Bio-Rex 70 column with urea solution (pH 3. 0) as an eluent, and a and β two subunits were isolated.Their molecula...R-phycocyanin (RPC) of Porphyra haitanensis (T. J. Chang et B. F. Zheng )' was chromatographed on Bio-Rex 70 column with urea solution (pH 3. 0) as an eluent, and a and β two subunits were isolated.Their molecular weights were determined on SDS-PAGE at 18 400 and 20 500, respetively,while those of a and β subunits of allophycocyanin (APC) at 18 800 and 19 700, respectively,and those of RPC and APC were at 117 000 and 122 000,respectively.Both the molar ratio of a and β subests of RPC and APC were 1:1, and the subunit composition was confirmed to be (αβ )3.It was ascertained that in RPC αsubunit contains one chromophore phycocyanobilin (PCB) and β subunit has one chromophore PCB and one phycoerythrobilin (PEB), while in APC both α and βsubunits contain one PCB.展开更多
A new phycocyanin（PC） fluorescent subunit namedβ_2（18kDa） was isolated and characterized by both SDS-PAGE and isoelectric focusing（IEF） from a species of cryptophytic alga Chroomonas placoidea.PC was separated ...A new phycocyanin（PC） fluorescent subunit namedβ_2（18kDa） was isolated and characterized by both SDS-PAGE and isoelectric focusing（IEF） from a species of cryptophytic alga Chroomonas placoidea.PC was separated and purified by ammonium sulfate sedimentation followed by two steps of Sephadex G-100 chromatography.After denatured in 4 mol/L urea for 48 h,PC was divided into two fractions by passing through a Sephacryl S-100 chromatography column twice.The blue fraction（S-1） containedβsubunits with a maximal absorbance at 595 nm in visible light region.While the green fraction（S-2） enriched inαsubunits showed a characteristic long wavelength absorbance at 680-700 nm region and exhibited a relatively low molecular weight of 9.4（α_1） and 8.5 kDa（α_2）.Fraction S-1 also consisted of two different fluorescent subunits with molecular weight of 20.1 kDa（β_1） and 18 kDa （β_2） and differed from each other on isoelectric points of pH 5.7（ft） and 6.0（ft）,respectively.Further investigation of peptide sequence will help a lot in elucidating the new subunit ft that was smaller in size and more neutral than the known ft subunit,and may provide an alternative explanation in structure of cryptophytic phycobiliproteins.展开更多
文摘R-phycocyanin (RPC) of Porphyra haitanensis (T. J. Chang et B. F. Zheng )' was chromatographed on Bio-Rex 70 column with urea solution (pH 3. 0) as an eluent, and a and β two subunits were isolated.Their molecular weights were determined on SDS-PAGE at 18 400 and 20 500, respetively,while those of a and β subunits of allophycocyanin (APC) at 18 800 and 19 700, respectively,and those of RPC and APC were at 117 000 and 122 000,respectively.Both the molar ratio of a and β subests of RPC and APC were 1:1, and the subunit composition was confirmed to be (αβ )3.It was ascertained that in RPC αsubunit contains one chromophore phycocyanobilin (PCB) and β subunit has one chromophore PCB and one phycoerythrobilin (PEB), while in APC both α and βsubunits contain one PCB.
基金granted by the National Science Fund of China(No.40976083)
文摘A new phycocyanin（PC） fluorescent subunit namedβ_2（18kDa） was isolated and characterized by both SDS-PAGE and isoelectric focusing（IEF） from a species of cryptophytic alga Chroomonas placoidea.PC was separated and purified by ammonium sulfate sedimentation followed by two steps of Sephadex G-100 chromatography.After denatured in 4 mol/L urea for 48 h,PC was divided into two fractions by passing through a Sephacryl S-100 chromatography column twice.The blue fraction（S-1） containedβsubunits with a maximal absorbance at 595 nm in visible light region.While the green fraction（S-2） enriched inαsubunits showed a characteristic long wavelength absorbance at 680-700 nm region and exhibited a relatively low molecular weight of 9.4（α_1） and 8.5 kDa（α_2）.Fraction S-1 also consisted of two different fluorescent subunits with molecular weight of 20.1 kDa（β_1） and 18 kDa （β_2） and differed from each other on isoelectric points of pH 5.7（ft） and 6.0（ft）,respectively.Further investigation of peptide sequence will help a lot in elucidating the new subunit ft that was smaller in size and more neutral than the known ft subunit,and may provide an alternative explanation in structure of cryptophytic phycobiliproteins.
