The nitrogen source-dependent 126-kDa protein from Synechococcus PCC 7942 plasmalemma: a trimer of the NrtA nitrate-binding protein.
Expression of a 126-kDa protein in the plasmalemma (cytoplasmic membrane) from Synechococcus PCC 7942 is dependent on the nitrogen source. Polyclonal antibody raised against the NrtA protein reacted with the 126-kDa protein. Two peptide sequences from the 126-kDa protein were retrieved in NrtA. FPLC purification of plasmalemma solubilised in Triton X-100 gave a fraction consisting mainly of a 126-kDa component (72.6%), as shown by sedimentation velocity. Equilibrium sedimentation of the same fraction gave evidence of the existence of an oligomeric structure (Ka = 2 x 10(3) and 2.9 subunits). Thus, the 126-kDa protein is considered as a trimeric arrangement of the 45-kDa protein in the plasmalemma.
Fresneau
C
C
Laboratoire de Bioénergétique Membranaire, A.N. Bakh Institute of Biochemistry, Russian Academy of Science, Moscow. chantal.fresneau@bioen.u-psud.fr
Zinovieva
M
M
Blanot
D
D
Batelier
G
G
Arrio
B
B
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002499:Centrifugation, Density Gradient; D002851:Chromatography, High Pressure Liquid; D000458:Cyanobacteria / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008970:Molecular Weight; D009566:Nitrates / Q000378:metabolism*; D020836:Protein Structure, Quaternary; D021122:Protein Subunits
D000596:Amino Acids; D001426:Bacterial Proteins; D002352:Carrier Proteins; D008565:Membrane Proteins; D009566:Nitrates; D021122:Protein Subunits