EC Number   |
Subunits |
Reference |
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   7.1.1.10 | More |
analysis of the 3.2-A-resolution cryo-EM structure of the ferredoxin (Fd)-NDH-1L complex from Thermosynechococcus elongatus, NdhS is a constitutive component of NDH-1L and adopts an SH3-like fold, it is the Fd-binding subunit in NDH-1L. But it is unlikely NdhS plays a major role in direct Fd binding, even though the C-terminal 10-residue tail of NdhS is not visible in the EM density. It is more likely that NdhS makes its contribution indirectly as a foothold holding the transient NdhV in the NDH-1L complex for Fd binding. NdhS is required for accumulation of NdhV in the thylakoid membranes but not vice versa. NdhV is a transient subunit of NDH-1L, NdhV can function as an Fd-binding cofactor, guiding the association of Fd to the NDH-1L complex. NdhV may also accelerate the electron transfer rate by helping stabilize the Fd-NdhI interface in an electron transfer-competent conformation. NdhO might be a negative regulator of NDH-CET activity. The Fd-NDH-1L complex structure reveals that all four OPS regulatory subunits are in close vicinity to the electron transport pathway in NDH-1L-NdhL adjacent to the electron acceptor PQ cavity while NdhV, NdhS, and NdhO are at the electron donor Fd-binding site. The peripheral arm of NDH-1L adopts a cylinder-shaped architecture organized by four conserved core subunits (NdhH-NdhK) and two OPS structural subunits (NdhM and NdhN). The central axis of the cylinder is the redox chain of three [4Fe-4S] clusters composed of distal and medial clusters N6a and N6b coordinated in NdhI and terminal cluster. OPS regulatory subunits NdhS, NdhV, and NdhO all fold into small compact structures, binding to the apex of the peripheral arm. NdhS stably sits in a groove of NdhI, holding NdhV to attach to and buttress NdhI for Fd binding and electron transfer. On the opposite side of NdhI, NdhO is secured on the surface of the peripheral arm through interactions with NdhJ, NdhK, and NdhN |
-, 761988 |
| 7.1.1.10 | More |
composition, structure, and membrane localization and topology of the different NDH1 complexes, detailed overview |
761330 |
| 7.1.1.10 | More |
determination of the presence of a supercomplex composed of NDH-1, CpcG2, and PSI (NDH-1-CpcG2-PBS-PSI), structure-function relationship and analysis, overview |
762156 |
| 7.1.1.10 | More |
different NDH-1 complexes are found in the cyanobacterial thylakoid membrane. All of these complexes contain the NDH-1M module, which is composed of both hydrophilic and hydrophobic domains and is presently known to comprise 14 subunits (NdhA-C, NdhE, NdhG-O, and NdhS). NDH-1M has no physiological function by itself but represents an assembly intermediate for functional NDH-1 complexes. The NdhH-K, NdhO, and NdhS subunits form the hydrophilic domain, while the NdhA-C, NdhE, NdhG, and NdhL-N subunits are components of the hydrophobic membrane domain. The NdhO subunit, assigned to the hydrophobic domain, is shown to strongly interact with the NdhI and NdhK subunits of the hydrophilic domain, thereby providing flexibility and maximal NDH-dependent cyclic electron transport (NDH-CET) activity under high-light conditions. The NdhS subunit of the hydrophilic domain of NDH-1M is essential for binding of Fd, the putative electron donor to cyanobacterial NDH-1 complexes, as in the case of plant chloroplasts |
760346 |
| 7.1.1.10 | More |
different NDH-1 complexes are found in the cyanobacterial thylakoid membrane. All of these complexes contain the NDH-1M module, which is composed of both hydrophilic and hydrophobic domains and is presently known to comprise 14 subunits (NdhA-C, NdhE, NdhG-O, and NdhS). NDH-1M has no physiological function by itself but represents an assembly intermediate for functional NDH-1 complexes. The NdhH-K, NdhO, and NdhS subunits form the hydrophilic domain, while the NdhA-C, NdhE, NdhG, and NdhL-N subunits are components of the hydrophobic membrane domain. The NdhO subunit, assigned to the hydrophobic domain, is shown to strongly interact with the NdhI and NdhK subunits of the hydrophilic domain, thereby providing flexibility and maximal NDH-dependent cyclic electron transport (NDH-CET) activity under high-light conditions. The NdhS subunit of the hydrophilic domain of NDH-1M is essential for binding of Fd, the putative electron donor to cyanobacterial NDH-1 complexes, as in the case of plant chloroplasts. The maturation factor, the Slr1097 (CRR6) protein, is involved in complex assembly in Synechocystis sp. PCC6803. The Synechocystis sp. PCC6803 genome contains six different ndhD genes (ndhD1-6) and three different ndhF genes (ndhF1, ndhF3, and ndhF4) |
760346 |
| 7.1.1.10 | More |
NDH adopts an L-shaped structure that is characteristic of respiratory NADH dehydrogenase complexes. NDH possesses 11 of the 14 core complex I subunits, as well as several oxygenic-photosynthesis-specific (OPS) subunits that are conserved from cyanobacteria to plants. However, the three core complex I subunits that are involved in accepting electrons from NAD(P)H are notably absent in NDH. OPS subunits NdhO and NdhS and the beta-hairpin of core subunit NdhI, surface model, structure-function analysis, overview |
762007 |
| 7.1.1.10 | More |
several strains of Thermosynechococcus elongatus are constructed by adding a His-tag to different subunits of NDH-1. Two strains with His-tag on CupA and NdhL are successfully used to isolate NDH-1 complexes by one-step Ni2+ column chromatography, revealing the presence of three complexes with molecular masses of about 450, 300 and 190 kDa, which are identified by MS to be NDH-1L, NDH-1M and NDH-1S respectively. A larger complex of about 490 kDa is also isolated from the NdhL-His strain. This complex, designated NDH-1MS, is composed of NDH-1M and NDH-1S (EC 7.1.1.11). The NDH-1L complex is recovered from wild-type cells of Thermosynechococcus elongatus by Ni2+ column chromatography. NdhF1 subunit present only in NDH-1L has a sequence of -HHDHHSHH- internally, which appears to have an affinity for the Ni2+ column. NDH-1S or NDH-1M are not recovered from wild-type cells by chromatography of this kind. The BN/SDS/PAGE analysis of membranes solubilized by a low concentration of detergent indicated the presence of abundant NDH-1MS, but not NDH-1M or NDH-1S. Thus, NDH-1S is associated with NDH-1M in vivo. Selection of the subunit for His tagging is crucial for isolation of NDH-1 complexes |
760518 |
| 7.1.1.10 | More |
subunit NdhP is essential for stable NDH-1L assembly in Thermosynechococcus elongatus. It is localized in the NDH-1L specific distal unit of the NDH-1 complex, that is formed by the subunits NdhD1 and NdhF1 |
762253 |
| 7.1.1.10 | More |
the subunit composition of the plant NDH-1 complex, overview. Chloroplast NDH-1 is structurally subdivided into five subcomplexes: A, B, M (membrane), L (lumen), and ED (electron donor). The 11 plastid-encoded subunits (NdhA-K) are conserved in all NDH-related protein complexes and form an L-shaped skeleton. Chloroplast NDH-1 is a large protein complex consisting of these 11 subunits and more than 19 nucleus-encoded subunits. Subcomplex A corresponds to the Q module of respiratory NADH dehydrogenases and includes four plastid-encoded subunits (NdhH-K). All the cofactors required for electron transport, from the soluble electron donor to the complex to plastoquinone (PQ), are probably harbored by these subunits. Chloroplast NDH-1 includes four additional nuclear-encoded subunits (NdhL-O). Subcomplex M consists of seven plastid-encoded subunits (NdhA-G) and forms the membrane arm that functions in proton translocation across the membrane (the P module in respiratory NADH dehydrogenase). Subcomplex B is composed of five subunits (PnsB1-5) and is specific to chloroplast NDH-1. PnsB4 and PnsB5 have transmembrane domains, whereas PnsB1, PnsB2, and PnsB3 are localized to the stroma side, probably anchored on PnsB4 and PnsB5. Although the molecular function of subcomplex B remains unelucidated, defects in its subunits result in the destabilization of the total complex. Subcomplex L contains at least five subunits (PnsL1-5) and is also specific to chloroplast NDH-1. Phylogenetically, the occurrence of subcomplex L is linked to the formation of a supercomplex between NDH-1 and PSI. Three of the subcomplex L subunits (PnsL1-3) show sequence similarities to lumenal subunits of PSII: PnsL1 is PsbP-like protein 2 (PPL2), and PnsL2 and PnsL3 are forms of PsbQ-like protein (PQL). In PSII, PsbP and PsbQ stabilize the PSII supercomplex by interacting with CP26 and CP47, supporting the idea that subcomplex L stabilizes the NDH-1-PSI supercomplex at the lumen side. Three subunits of subcomplex ED - NdhS, NdhT, and NdhU - have been identified by proteomic analysis of the NDH-1-PSI supercomplex. NdhS is involved in ferredoxin (Fd) binding. NdhT and NdhU are J and J-like proteins, respectively, that have a transmembrane domain and likely form a heterodimer required for stabilizing NdhS. NdhV is a subunit loosely bound to subcomplex ED, forming the most fragile part of the complex. Subcomplex ED interacts with subcomplex A to form the Fd-binding site, which includes the Fd-oxidizing site |
760346 |
| 7.1.1.10 | More |
the subunit composition of the plant NDH-1 complex, overview. Chloroplast NDH-1 is structurally subdivided into five subcomplexes: A, B, M (membrane), L (lumen), and ED (electron donor). The 11 plastid-encoded subunits (NdhA-K) are conserved in all NDH-related protein complexes and form an L-shaped skeleton. Chloroplast NDH-1 is a large protein complex consisting of these 11 subunits and more than 19 nucleus-encoded subunits. Subcomplex A corresponds to the Q module of respiratory NADH dehydrogenases and includes four plastid-encoded subunits (NdhH-K). All the cofactors required for electron transport, from the soluble electron donor to the complex to plastoquinone (PQ), are probably harbored by these subunits.ChloroplastNDH-1includes four additional nuclear-encoded subunits (NdhL-O). Subcomplex M consists of seven plastid-encoded subunits (NdhA-G) and forms the membrane arm that functions in proton translocation across the membrane (the P module in respiratory NADH dehydrogenase). Subcomplex B is composed of five subunits (PnsB1-5) and is specific to chloroplast NDH-1. PnsB4 and PnsB5 have transmembrane domains, whereas PnsB1, PnsB2, and PnsB3 are localized to the stroma side, probably anchored on PnsB4 and PnsB5. Although the molecular function of subcomplex B remains unelucidated, defects in its subunits result in the destabilization of the total complex. Subcomplex L contains at least five subunits (PnsL1-5) and is also specific to chloroplast NDH-1. Phylogenetically, the occurrence of subcomplex L is linked to the formation of a supercomplex between NDH-1 and PSI. Three of the subcomplex L subunits (PnsL1-3) show sequence similarities to lumenal subunits of PSII: PnsL1 is PsbP-like protein 2 (PPL2), and PnsL2 and PnsL3 are forms of PsbQ-like protein (PQL). In PSII, PsbP and PsbQ stabilize the PSII supercomplex by interacting with CP26 and CP47, supporting the idea that subcomplex L stabilizes the NDH-1-PSI supercomplex at the lumen side. Three subunits of subcomplex ED - NdhS, NdhT, and NdhU - have been identified by proteomic analysis of the NDH-1-PSI supercomplex. NdhS is involved in ferredoxin (Fd) binding. NdhT and NdhU are J and J-like proteins, respectively, that have a transmembrane domain and likely form a heterodimer required for stabilizing NdhS. NdhV is a subunit loosely bound to subcomplex ED, forming the most fragile part of the complex. Subcomplex ED interacts with subcomplex A to form the Fd-binding site, which includes the Fd-oxidizing site |
760346 |
