R. Ficner et R. Huber, REFINED CRYSTAL-STRUCTURE OF PHYCOERYTHRIN FROM PORPHYRIDIUM-CRUENTUMAT 0.23-NM RESOLUTION AND LOCALIZATION OF THE GAMMA-SUBUNIT, European journal of biochemistry, 218(1), 1993, pp. 103-106
The three-dimensional structure of the light-harvesting pigment-protei
n b-phycoerythrin from the red alga Porphyridium cruentum has been det
ermined at 0.23-nm resolution. The b-phycoerythrin structure is very s
imilar to the structure of B-phycoerythrin from Porphyridium sordidum.
Besides three non-identical residues there are only small differences
between b-phycoerythrin and B-phycoerythrin alpha and beta subunits,
respectively. In the crystals b-phycoerythrin forms an (alphabeta)6 he
xamer (molecular mass: 236 kDa), whereas B-phycoerythrin additionally
contains a 30-kDa gamma subunit. The comparison of the b-phycoerythrin
and B-phycoerythrin electron-density maps clearly reveals, that the g
amma subunit is located inside the (alphabeta)6 aggregate.