title: Identification of NdhL and Ssl1690 (NdhO) in NDH-1L and NDH-1M complexes of Synechocystis sp. PCC 6803.
abstract: The subunit compositions of two types of NAD(P)H dehydrogenase complexes of Synechocystis sp. PCC 6803, NDH-1L and NDH-1M, were studied by two-dimensional blue-native/SDS-PAGE followed by electrospray tandem mass spectrometry. Fifteen proteins were observed in NDH-1L including hydrophilic subunits (NdhH, -K, -I, -J, -M, and -N) and hydrophobic subunits (NdhA, -B, -E, -G, -D1, and -F1). In addition, NdhL and a novel subunit, Ssl1690 (designated NdhO), were shown to be components of this complex. All subunits mentioned above were present in the NDH-1M complex except NdhD1 and NdhF1. NdhL and Ssl1690 (NdhO) were homologous to hypothetical proteins encoded by genomic DNA in higher plants, suggesting that chloroplast NDH-1 complexes contain related subunits. Diagnostic sequence motifs were found for both NdhL and NdhO homologous proteins. Analysis of ndhL deletion mutant (M9) revealed the presence of assembled NDH-1L and NDH-1M complexes, but these complexes appear to be functionally impaired in the absence of NdhL. Both NDH-1 complexes were absent in the ndhB deletion mutant (M55).
authors.affiliation: Department of Biology, Plant Physiology and Molecular Biology, FIN-20014 University of Turku, Finland.
authors.forename: Natalia
authors.initials: N
authors.lastname: Battchikova
authors.forename: Pengpeng
authors.initials: P
authors.lastname: Zhang
authors.forename: Stephen
authors.initials: S
authors.lastname: Rudd
authors.forename: Teruo
authors.initials: T
authors.lastname: Ogawa
authors.forename: Eva-Mari
authors.initials: EM
authors.lastname: Aro
mesh_terms: D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D019295:Computational Biology; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel; D017353:Gene Deletion; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009154:Mutation; D009252:NADPH Dehydrogenase / Q000096:biosynthesis*; D010455:Peptides / Q000737:chemistry; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021122:Protein Subunits / Q000096:biosynthesis*; D017386:Sequence Homology, Amino Acid; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D046939:Synechocystis / Q000378:metabolism*
chemical_list: D010455:Peptides; D021122:Protein Subunits; D009252:NADPH Dehydrogenase