A1 Refereed original research article in a scientific journal
Structural characterization of NDH-1 complexes of Thermosynechococcus elongatus by single particle electron microscopy
Authors: Arteni AA, Zhang PP, Battchikova N, Ogawa T, Aro EM, Boekema EJ
Publisher: ELSEVIER SCIENCE BV ELSEVIER SCIENCE BV
Publication year: 2006
Journal:: BBA - Bioenergetics
Journal name in source: BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS
Journal acronym: BBA-BIOENERGETICS
Volume: 1757
Issue: 11
First page : 1469
Last page: 1475
Number of pages: 7
ISSN: 0005-2728
DOI: https://doi.org/10.1016/j.bbabio.2006.05.042
Abstract
The structure of the multifunctional NAD(P)H dehydrogenase type 1 (NDH-1) complexes from cyanobacteria was investigated by growing the wild type and specific ndh His-tag mutants of Thermosynechococcus elongatus BP-1 under different CO2 conditions, followed by an electron microscopy (EM) analysis of their purified membrane protein complexes. Single particle averaging showed that the complete NDH-1 complex (NDH-1L) is L-shaped, with a relatively short hydrophilic arm. Two smaller complexes were observed, differing only at the tip of the membrane-embedded ann. The smallest one is considered to be similar to NDH-1M, lacking the NdhD1 and NdhF1 subunits. The other fragment, named NDH-1I, is intermediate between NDH-1L and NDH-1M and only lacks a mass compatible with the size of the NdhF1 subunit. Both smaller complexes were observed under low- and high-CO2 growth conditions, but were much more abundant under the latter conditions. EM characterization of cyanobacterial NDH-1 further showed small numbers of NDH-1 complexes with additional masses. One type of particle has a much longer peripheral ann, similar to the one of NADH: ubiquinone oxidoreductase (complex 1) in E. coli and other organisms. This indicates that Thermosynechococcus elongatus must have protein(s) which are structurally homologous to the E. coli NuoE, -F, and -G subunits. Another low-abundance type of particle (NDH-1U) has a second labile hydrophilic arm at the tip of the membrane-embedded arm. This U-shaped particle has not been observed before by EM in a NDH-1 preparation. (c) 2006 Elsevier B.V. All rights reserved.
The structure of the multifunctional NAD(P)H dehydrogenase type 1 (NDH-1) complexes from cyanobacteria was investigated by growing the wild type and specific ndh His-tag mutants of Thermosynechococcus elongatus BP-1 under different CO2 conditions, followed by an electron microscopy (EM) analysis of their purified membrane protein complexes. Single particle averaging showed that the complete NDH-1 complex (NDH-1L) is L-shaped, with a relatively short hydrophilic arm. Two smaller complexes were observed, differing only at the tip of the membrane-embedded ann. The smallest one is considered to be similar to NDH-1M, lacking the NdhD1 and NdhF1 subunits. The other fragment, named NDH-1I, is intermediate between NDH-1L and NDH-1M and only lacks a mass compatible with the size of the NdhF1 subunit. Both smaller complexes were observed under low- and high-CO2 growth conditions, but were much more abundant under the latter conditions. EM characterization of cyanobacterial NDH-1 further showed small numbers of NDH-1 complexes with additional masses. One type of particle has a much longer peripheral ann, similar to the one of NADH: ubiquinone oxidoreductase (complex 1) in E. coli and other organisms. This indicates that Thermosynechococcus elongatus must have protein(s) which are structurally homologous to the E. coli NuoE, -F, and -G subunits. Another low-abundance type of particle (NDH-1U) has a second labile hydrophilic arm at the tip of the membrane-embedded arm. This U-shaped particle has not been observed before by EM in a NDH-1 preparation. (c) 2006 Elsevier B.V. All rights reserved.