@article{BergerEllersiekWesthoffetal.1993, author = {Berger, Susanne and Ellersiek, Ulrike and Westhoff, Peter and Steinm{\"u}ller, Klaus}, title = {Studies on the expression of NDH-H, a subunit of the NAD(P)H-plastoquinone-oxidoreductase of higher-plant chloroplasts}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31283}, year = {1993}, abstract = {The plastid genomes of higher plants contain eleven reading frames (ndhA-K) that are homologous to genes encoding subunits of the mitochondrial NADH-ubiquinone-oxidoreductase (complex I). The carboxyterminal end of the NDH-H subunit from rice (Oryza sativa L.) was expressed as a fusion protein in Escherichia coli and antibodies against the fusion protein were generated in rabbits. The antibody was used to study the expression of NDH-H, and the following results were obtained: (i) NDH-H is expressed in mono- and dicotyledonous plants, (ii) NDH-H is localized on the stroma lamellae of the thylakoid membrane and (iii) NDH-H is expressed in etioplasts. Together with the finding that two other ndh genes (ndhI and ndhK) are expressed in plastids, these results point to the existence of an NAD(P)H-plastoquinone-oxidoreductase on the thylakoid membrane. The possible function of the enzyme in plastids is discussed and it is suggested that it works in balancing the ATP/ADP and the NADPH/NADP ratios during changing external (i.e. light) or internal (i.e. ATP and NADPH demands of biosynthetic pathways of the plastid) conditions.}, language = {en} } @article{BergerEllersiekKinzeltetal.1993, author = {Berger, Susanne and Ellersiek, Ulrike and Kinzelt, Dagmar and Steinm{\"u}ller, Klaus}, title = {Immunopurification of a subcomplex of the NAD(P)H-plastoquinone-oxidoreductase from the cyanobacterium Synechocystis sp. PCC6803}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31249}, year = {1993}, abstract = {An antibody against the NDH-K subunit of the NAD(P)H-dehydrogenase from the cyanobacterium Synechocystis sp. PCC6803 was used to isolate a subcomplex ofthe enzyme from Triton X-lOO solubilized total membranes by immunoaffinity chromatography. The isolated subcomplex consisted of seven major polypeptides with molecular masses of 43, 27, 24, 21, 18, 14 and 7 kDa. The amino-terminal amino acid sequences of the polypeptides were determined. By comparing the sequences with the amino acid sequences deduced from DNA. three proteins were identified as NDH-H (43 kDa). NDH-K (27 kDa) and NDH-J (24 kDa). A fourth subunit (NDH-J, 21 kDa) was identified by Western blot analysis with an NDH-J antibody.}, language = {en} } @article{BergerEllersiekSteinmueller1991, author = {Berger, Susanne and Ellersiek, Ulrike and Steinm{\"u}ller, Klaus}, title = {Cyanobacteria contain a mitochrondrial complex I-homologous NADH-dehydrogenase}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31223}, year = {1991}, abstract = {Thylakoid and cytoplasmic membranes of the cyanobacterium Syncchocystis sp. PCC 6803 were purified by sucrose gradient centrifugation. Both membranes oxidize NADH in a rotenone-sensitive reaction. Antibodies prepared against psbG/ndhKand ndhJ fusion proteins detect the corresponding polypeptides in both membrane preparations. This demonstrates that a NADH-dehydrogenase, homologous to the mitochondrial NADHubiquinone-oxidoreductase (complex I of the respiratory chain) is present in cyanobacteria, The NADH-dehydrogenase can be solubilized with the detergent /-D-dodecylmaltoside. Sedimentation analysis of the solubilized enzyme on a sucrose gradient indicates that it is a multisubunit protein complex.}, language = {en} }