The structure of form I crystals of d-ribulose-1,5-diphosphate carboxylase

Abstract

Single crystals of D-ribulose-1,5-diphosphate carboxylase from tobacco leaves, Nicotiana tabacum (variety Turkish Samsun), have been examined by X-ray diffraction, electron microscopy, and optical diffraction. Twelve molecules are loosely packed into a body-centered cubic unit cell, space group 14 1 32 with cell dimension a = 383 Å. The asymmetric unit is one quarter of a molecule, and the minimum molecular symmetry is 222. This symmetry when combined with estimates of the two subunit masses and stoichiometry is compatible with a molecular structure of the composition L 8 S 8 (L is large subunit, S is small). If all bonds between large and small subunits are equivalent, the true molecular symmetry is 422; this symmetry is consistent with molecular images in micrographs.

Unique and Overlapping Expression Patterns among Members of Photosynthesis-Associated Nuclear Gene Families in Arabidopsis

“…The physiological fine-tuning of the cell would be further enhanced if protein family members cooperated in multimeric complexes of variable composition. RbcS and Lhc proteins can interact with members of the same family to form heterodimers, trimers, and higher-order complexes (Baker et al, 1975;Jansson, 1994;Ben-Shem et al, 2003;Lucinski et al, 2006). However, the existence of overlapping expression among members of these gene families is a prerequisite for such type of interaction to occur in vivo.…”

“…Rubisco is a multimeric enzyme consisting of eight small subunits and eight large subunits (Baker et al, 1975), and while the large subunits are encoded by a single chloroplast gene (Bedbrook et al, 1979), the small subunits are encoded by a family of nuclear genes (Dean et al, 1989). In Arabidopsis (Arabidopsis thaliana), the RbcS gene family comprises four members (RbcS1A, RbcS1B, RbcS2B, RbcS3B) that have been divided into two subfamilies, A and B, on the basis of linkage and sequence similarities (Krebbers et al, 1988).…”

The stoichiometry of polypeptide chains in the pyruvate dehydrogenase multienzyme complex of E. Coli determined by a simple novel method

“…of the native enzyme and of its denatured sub-units suffices to establish the number of protein chains in the oligomer. With larger structures, however, evidence may often have to be drawn from other sources, such as X-ray diffraction analysis, electron microscopy and arguments from symmetry [ 1,2] .…”

Cloning, mapping, and in vitro transcription-translation of the gene for the large subunit of ribulose-1,5-bisphosphate carboxylase from spinach chloroplasts

“…In most plants the chloroplast enzyme ribulose-1,5-bisphosphate carboxylase [RuP2 carboxylase; 3-phospho-D-glycerate carboxy-lyase (dimerizing), EC 4.1.1.39] is composed of eight identical large subunits (LS) and eight identical small subunits (1). Various methods have shown that the small subunit is coded by nuclear DNA and LS is coded by chloroplast DNA (cpDNA) (2).…”