Three-dimensional structures of C-phycocyanin and B-phycoerythrin at 5-A resolution.

Three-dimensional structures of C-phycocyanin and B-phycoerythrin at 5-A resolution.

Single crystal x-ray diffraction studies are proceeding on two phycobiliproteins: C-Phycocyanin from Anabaena variabilis and B-Phycoerythrin from Porphyridium cruentum. C-Phycocyanin consists of six alpha and six beta subunits. A three-dimensional x-ray diffraction study of this light-harvesting protein (P6(3); a = b = 154.1 A, c = 40.1 A) at 5-A resolution shows that the molecule is 110 A in d...

Characterization of R-phycocyanin. Chromophore content of R-phycocyanin and C-phycoerythrin.

R-phycocyanin was purified from two independent isolates of the unicellular red alga Porphyridium cruentum. At pH 7.0 the protein sediments as a single component with s 20,w of 5.98 S (at 2 mg/ml, gamma/2=0.02). Over a protein concentration range of 0.2 to 0.5 mg/ml (gamma/2=0.16), sedimentation equilibrium gave a molecular weight of 103,000 +/- 6,000 with no evidence of heterogeneity. In commo...

High-resolution crystal structures of trimeric and rod phycocyanin.

The phycobilisome light-harvesting antenna in cyanobacteria and red algae is assembled from two substructures: a central core composed of allophycocyanin surrounded by rods that always contain phycocyanin (PC). Unpigmented proteins called linkers are also found within the rods and core. We present here two new structures of PC from the thermophilic cyanobacterium Thermosynechococcus vulcanus. W...

The three-dimensional structures of methanol dehydrogenase from two methylotrophic bacteria at 2.6-A resolution.

The structures of methanol dehydrogenase (MEDH) from two closely related methylotrophic bacteria, Methylophilus methylotrophus and W3A1, have been determined at 2.6-A resolution. The molecule, a quinoprotein of molecular mass of about 138 kDa, contains two heavy (H) and two light (L) subunits of unknown sequence and two molecules of noncovalently associated pyrroloquinoline quinone. The two enz...

Dynamic Analysis of Three Dimensional Asymmetric Isolated Structures