The PAGE (lane 1 and 2) and IEF (lane 3 and 4) of the purified R-PE in native situation.

<p>The PAGE had a 6.5% (w/v) separation gel in the neutral buffer system and the IEF had 5.5% (w/v) polyacrylamide gel in a pH range from 4.0 to 6.5. Lane 1 and 3 yellow fluorescent bands of the R-PE in native red color under UV-light at 365 nm; lane 2 and 4 blue bands of the R-PE showed after the gel was stained by Coomassie Blue G-250.</p

The polypeptide analysis of the purified R-PE by SDS-PAGE.

<p>The SDS-PAGE was performed with a gradient separating gel of 13%-17% (w/v) in pH 9.2 Tris-HCl buffer and 4% (w/v) stacking gel in pH 6.8 Tris-HCl buffer. Lane 1 and 3 showed the polypeptide bands after Coomassie Blue G-250 staining. Lane 2 and 4 showed fluorescent bands of the subunits under UV-light at 365 nm after Zn(SO4)2 staining. Lane M showed marker proteins. The right part was the profile curve corresponding to band density and area of the Coomassie Blue G-250 stained pattern of the SDS-PAGE.</p

Absorption (solid line) and fluorescent emission (dash line) spectra of the purified R-PE.

<p>The ratio of A₅₆₆/A₂₈₀ reaches 5.26. The fluorescent emission spectrum was recorded in pH 7.0 phosphate buffer on the excitation at 495 nm. The spectra were normalized to the absorbance at 566 nm and to the fluorescent emission at 577 nm, respectively.</p

Absorption spectra of three R-PE samples in pH 7.0 phosphate buffer.

<p>(a) The phycobiliprotein extract; (b) the R-PE fraction from the gel filtration on Sepharose CL-4B; (c) the R-PE fraction from the gel filtration on Sephadex G-150. The spectra were normalized to the absorbance at 566 nm.</p

The isolation of the R-PE extracted from marine red alga <i>P</i>. <i>urceolata</i> by gel filtrations.

<p>(a) The gel filtration on Sepharose CL-4B which was developed with 50 mM phosphate buffer (pH 7.0) containing 4% (v/v) Triton X-100; (b) the gel filtration on Sephadex G-150 (solid line) developed with 50 mM phosphate buffer (pH 7.0) and the chromatography of Triton X-100 micelle on Sephadex G-150 (dash line) developed with 50 mM phosphate buffer (pH 7.0).</p

The purification of the isolated R-PE by the ion exchange chromatography on DEAE Sepharose FF.

<p>The chromatography was developed at 0.5 ml/min with a linear gradient of NaCl from 0–400 mM in 500 ml of 25 mM phosphate buffer (pH 7.0). After the gradient elution, the column was eluted with 1500 mM NaCl in 25 mM phosphate buffer at 0.5 ml/min.</p

The polypeptide examination of the purified R-PE by IEF in denaturing situation.

<p>Lane 1 and 2 in a pH range from 4.0 to 6.5 and lane 3 and 4 in a pH range from 3.0 to 10.0. The polypeptide bands were observed in native red color (lane 2), in blue color after Coomassie Blue G-250 staining (lane 4) and in fluorescence (lane 1 and 3) under UV-light at 365 nm.</p

The SDS-PAGE analysis of the subunits occurred at pH 5.0 (low pI band, L) and at pH 5.8 (high pI band, H) in the denaturing IEF.

<p>The gel disk of the low pI band (lane L) was cut out from the IEF gel rod and equilibrated in SDS solution at 60C for 30 min, and that of the high pI band (lane H) at 60C for 15 min before they were loaded on the SDS-PAGE with 13% slab gel in pH 9.2 Tris-HCl. The subunits were showed in blue bands after Coomassie Blue G-250 staining and in fluorescence bands under UV-light at 365 nm after Zn(SO₄)₂ staining. Lane M showed marker proteins and lane PE was the prepared R-PE.</p

The mass spectra of γ subunit γ^34.6 (a) and γ^31.6 (b) measured by MALDI-TOF/TOF mass spectrometry.

<p>The mass spectra of γ subunit γ^34.6 (a) and γ^31.6 (b) measured by MALDI-TOF/TOF mass spectrometry.</p

The resolution of AP in Bis-tris-HEPES-MES buffer system without stacking gel.

<p>The PAGE was carried out with a resolving gel of 9% in pH 6.5 Bis-tris−HEPES−MES buffer and with no stacking gel exclusively for the AP preparation. (a) the bands in natural colors, (b) the bands of native state in grey scale without red filter, (c) the bands of native state in grey scale with red filter, (d) the bands in fluorescence under UV-light at 365 nm and (e) the bands stained by Coomassie Blue G-250. The Tricine−Bis-tris electrode buffers in pH 6.3 were used in the PAGE. The sample used in the PAGE was the R-PC and AP fraction from the ion exchange chromatography.</p