Preliminary X-ray crystallographic study of wild-type and mutant ribulose-1,5-bisphosphate carboxylase/oxygenase from Chlamydomonas reinhardtii.
Ribulose-1,5-bisphosphate carboxylase/oxygenase is the key enzyme for photosynthesis. The wild-type and mutant (amino-acid substitutions in the catalytically important loop 6 region) enzymes from Chlamydomonas reinhardtii, a unicellular green alga, were crystallized. Wild-type, single-mutant (V331A) and two double-mutant (V331A/T342I and V331A/G344S) proteins were activated with cofactors CO2 and Mg2+, complexed with the substrate analog 2'-carboxyarabinitol-1,5-bisphosphate, and crystallized in apparently isomorphous forms. Unit-cell determinations have been completed for three of the enzymes. They display orthorhombic symmetry with similar cell parameters: wild type a = 130.4, b = 203. 3, c = 208.5 A; single mutant (V331A) a = 128.0, b = 203.0, c = 207. 0A; and double mutant (V331A/T342I) a = 130.0, b = 202.1, c = 209.7 A. Crystals of the wild-type and single-mutant (V331A) enzymes diffracted to approximately 2.8 A. A small crystal of the double-mutant (V331A/T342I) enzyme diffracted to approximately 6 A. A partial data set (68% complete) of the wild-type protein has been collected at room temperature to about 3.5 A.
Chemistry Department, University of Nebraska-Lincoln, Lincoln, NE 68588-0304, USA.
A
A
Yen
E J
EJ
Haas
K M
KM
Selbo
C R
CR
Ross 2nd
R J
RJ
Spreitzer
J J
JJ
Stezowski
D019943:Amino Acid Substitution; D000818:Animals; D016825:Chlamydomonas reinhardtii / Q000201:enzymology* / Q000235:genetics; D003460:Crystallization; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D010940:Plant Proteins / Q000737:chemistry* / Q000302:isolation & purification; D011487:Protein Conformation; D015800:Protozoan Proteins / Q000737:chemistry* / Q000302:isolation & purification; D012273:Ribulose-Bisphosphate Carboxylase / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification
D010940:Plant Proteins; D015800:Protozoan Proteins; D012273:Ribulose-Bisphosphate Carboxylase