Nathan Nelson

Nathan Nelson
Tel Aviv University | TAU · Department of Biochemistry and Molecular Biology

PhD

About

389
Publications
44,843
Reads
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26,183
Citations
Introduction
Our lab concentrates on the study of membrane-proteins: Structure, function and molecular biology of photosystem I and other membrane complexes in higher plant chloroplasts. Plant PSI was solved to 3.1 A. Structural determination of super-complexes in biological membranes. Crystal structure of chloroplast photosystem II and ATP-synthase. Expression and structural determination of marine viruses-encoded membrane proteins. Harnessing Oxygenic Photosynthesis for Sustainable Energy Production.
Additional affiliations
October 1995 - present
Tel Aviv University
Position
  • Professor (Full)
October 1995 - present
Faculty of Life Sciences, Tel Aviv University
Position
  • Professor Emeritus

Publications

Publications (389)
Article
Full-text available
Water molecules play a pivotal functional role in photosynthesis, primarily as the substrate for Photosystem II (PSII). However, their importance and contribution to Photosystem I (PSI) activity remains obscure. Using a high-resolution cryogenic electron microscopy (cryo-EM) PSI structure from a Chlamydomonas reinhardtii temperature-sensitive photo...
Preprint
Full-text available
Photosystem II (PSII) generates an oxidant whose redox potential is high enough to enable water oxidation, a substrate so abundant that it assures a practically unlimited electron source for life on earth. Our knowledge on the mechanism of water photooxidation was greatly advanced by high-resolution structures of prokaryotic PSII. Here we show high...
Article
Full-text available
Photosynthesis in deserts is challenging since it requires fast adaptation to rapid night-to-day changes, that is, from dawn’s low light (LL) to extreme high light (HL) intensities during the daytime. To understand these adaptation mechanisms, we purified photosystem I (PSI) from Chlorella ohadii, a green alga that was isolated from a desert soil c...
Article
Full-text available
Photosystem I is defined as plastocyanin-ferredoxin oxidoreductase. Taking advantage of genetic engineering, kinetic analyses and cryo-EM, our data provide novel mechanistic insights into binding and electron transfer between PSI and Pc. Structural data at 2.74 Å resolution reveals strong hydrophobic interactions in the plant PSI-Pc ternary complex...
Article
Full-text available
Most of life’s energy comes from sunlight, and thus, photosynthesis underpins the survival of virtually all life forms. The light-driven electron transfer at photosystem I (PSI) is certainly the most important generator of reducing power at the cellular level and thereby largely determines the global amount of enthalpy in living systems (Nelson 201...
Article
Full-text available
Photosystem I is the most efficient photosynthetic enzyme with structure and composition highly conserved among all oxygenic phototrophs. Cyanobacterial Photosystem I is typically associated into trimers for reasons that are still debated. Almost universally, Photosystem I contains a number of long-wavelength-absorbing ‘red’ chlorophylls (Chls), th...
Preprint
Full-text available
Photosystem I is defined as plastocyanin-ferredoxin oxidoreductase. Taking advantage of genetic engineering, kinetic analyses and cryo-EM, our data provide novel mechanistic insights into binding and electron transfer between PSI and Pc. Structural data at 2.74 Å resolution reveals strong hydrophobic interactions in the plant PSI-Pc ternary complex...
Article
Full-text available
The ability of photosynthetic organisms to use sunlight as a sole source of energy is endowed by two large membrane complexes— photosystem I (PSI) and photosystem II (PSII). PSI and PSII are the fundamental components of oxygenic photosynthesis, providing oxygen, food and an energy source for most living organisms on Earth. Currently, high-resoluti...
Article
Full-text available
Temperature sensitive mutants have been widely used to study structure, biogenesis and function of a large variety of essential proteins. However, this method has not yet been exploited for the study of photosynthesis. We used negative selection to isolate temperature-sensitive-photoautotrophic (TSP) mutants in Chlamydomonas reinhardtii. From a pop...
Article
Oxygenic photosynthesis evolved more than 3 billion years ago in cyanobacteria. The increased complexity of photosystem I (PSI) became apparent from the high-resolution structures that were obtained for the complexes that were isolated from various organisms, ranging from cyanobacteria to plants. These complexes are all evolutionarily linked. In th...
Article
Full-text available
Solar energy harnessed by oxygenic photosynthesis supports most of the life forms on Earth. In eukaryotes, photosynthesis occurs in chloroplasts and is achieved by membrane-embedded macromolecular complexes that contain core and peripheral antennae with multiple pigments. The structure of photosystem I (PSI) comprises the core and light-harvesting...
Article
Full-text available
The evolution of photosynthesis from primitive photosynthetic bacteria to higher plants has been driven by the need to adapt to a wide range of environmental conditions. The red alga Cyanidioschyzon merolae is a primitive organism, which is capable of performing photosynthesis in extreme acidic and hot environments. The study of its photosynthetic...
Article
Full-text available
A single histidine addition to the C-terminus of PsaL of Synechocystis sp. PCC 6803 was previously reported by our lab to shift the trimer-to-monomer ratio of PSI in favor of the monomeric form. P700 re-reduction and NADP+ photo-reduction measurements of the PsaLHIS strain show no effect on PSI activity in comparison to the WT trimeric PSI. Crystal...
Article
Plant photosystem I (PSI) is one of the most intricate membrane complexes in nature. It comprises two complexes, a reaction center and light-harvesting complex (LHC), which together form the PSI-LHC supercomplex. The crystal structure of plant PSI was solved with two distinct crystal forms. The first, crystallized at pH 6.5, exhibitedP21 symmetry;...
Article
The ability of photosynthetic organisms to use the sun's light as a sole source of energy sustains life on our planet. Photosystems I (PSI) and II (PSII) are large, multi-subunit, pigment–protein complexes that enable photosynthesis, but this intriguing process remains to be explained fully. Currently, crystal structures of these complexes are avai...
Chapter
Plant photosystem I (PSI) is one of the most intricate membrane complexes in nature. It comprises two distinct building blocks; the reaction center and the lightharvesting complexes (LHC). They contain 16 subunits and over 200 prosthetic groups, including chlorophylls, carotenoids, quinines, phospholipids, glycolipids, and three iron-sulfur cluster...
Article
Full-text available
Modern energy production is required to undergo a dramatic transformation. It will have to replace fossil fuel use by a sustainable and clean energy economy while meeting the growing world energy needs. This review analyzes the current energy sector, available energy sources, and energy conversion technologies. Solar energy is the only energy sourc...
Article
Four elaborate membrane complexes carry out the light reaction of oxygenic photosynthesis. Photosystem I (PSI) is one of two large reaction centres responsible for converting light photons into the chemical energy needed to sustain life. In the thylakoid membranes of plants, PSI is found together with its integral light-harvesting antenna, light-ha...
Article
Full-text available
The need for energy and the associated burden are ever growing. It is crucial to develop new technologies for generating clean and efficient energy for society to avoid upcoming energetic and environmental crises. Sunlight is the most abundant source of energy on the planet. Consequently, it has captured our interest. Certain microalgae possess the...
Chapter
Oxygenic photosynthesis is the principal converter of sunlight into chemical energy on earth. The conversion of solar energy is catalyzed by four multi-subunit membrane protein complexes: photosystem I (PSI), photosystem II (PSII), the cytochrome b6-f complex (cytb 6f) and ATP-synthase (FOF1). These protein complexes are connected by soluble electr...
Article
Full-text available
Oxygenic photosynthesis is the principal converter of sunlight into chemical energy on Earth. Cyanobacteria and plants provide life with oxygen, food, fuel, fibers, and platform chemicals. Four multisubunit membrane proteins are involved: photosystem I (PSI), photosystem II (PSII), cytochrome b6f (cyt b6f) and ATP synthase (FOF1). Oxygenic photosyn...
Article
Full-text available
Oxygenic photosynthesis is the principal converter of sunlight into chemical energy on Earth. Cyanobacteria and plants provide the oxygen, food, fuel, fibers, and platform chemicals for life on Earth. The conversion of solar energy into chemical energy is catalyzed by two multisubunit membrane protein complexes, photosystem I (PSI) and photosystem...
Article
Full-text available
Extrusion of chloroquine (CQ) from digestive vacuoles through the Plasmodium falciparum CQ resistance transporter (PfCRT) is essential to establish CQ resistance of the malaria parasite. However, the physiological relevance of PfCRT and how CQ-resistant PfCRT gains the ability to transport CQ remain unknown. We prepared proteoliposomes containing p...
Patent
A cyanobacterial cell comprising a PSI complex which accepts electrons from at least one respiratory cytochrome is disclosed. Methods of generating same and use of same for the production of hydrogen gas are also disclosed.
Data
List of primers used in the construction of PsaJF. PsaJ was amplified with primers 5580 and 5581 and fused to PsaF fragment amplified with primers 5582 and 5583. The JF fusion gene was than ampified using ∼300 bp sequences containing the PsaF promoter and the PsaF down homology to create the entire gene cassette. This 970 bp fragment was cloned int...
Article
Full-text available
Life on earth is governed by light, chemical reactions, and the second law of thermodynamics, which defines the tendency for increasing entropy as an expression of disorder or randomness. Life is an expression of increasing order, and a constant influx of energy and loss of entropic wastes are required to maintain or increase order in living organi...
Article
Full-text available
Recent structural determinations and metagenomic studies shed light on the evolution of photosystem I (PSI) from the homodimeric reaction centre of primitive bacteria to plant PSI at the top of the evolutionary development. The evolutionary scenario of over 3.5 billion years reveals an increase in the complexity of PSI. This phenomenon of ever-incr...
Article
Full-text available
A ring of 8-15 identical c-subunits is essential for ion-translocation by the rotary electromotor of the ubiquitous F(O)F(1)-ATPase. Here we present the crystal structure at 3.4Å resolution of the c-ring from chloroplasts of a higher plant (Pisum sativum), determined using a native preparation. The crystal structure was found to resemble that of an...
Data
Comparison of the slowest types of motion of the green pea c-ring, c-ring of Bacillus pseudofirmus (PDB ID 2×2v) and c-ring of the bovine F1-c8 sub-complex (PDB ID 2xnd). The deformations of the corresponding types of motion (Table S1) are shown, colored by their GNM-derived cross-correlations, according to the color bar below, with negative (blue)...
Data
Comparison between normal mode analyses of different c-rings. For each ring [9], [10], [11], [12], [13], [14], [15], the GNM and ANM modes corresponding to motions of types I, II and III are specified (colored green, blue and red, respectively). Modes were matched according to the ANM deformations as well as the GNM cross-correlations, as exemplifi...
Data
Association of GNM and ANM modes. As all types of motion consisted of the same hinge regions (Fig. 3A), we matched the GNM and ANM modes using their inter-residue cross-correlations. For motion type I, derived from the average GNM1-2 mode, ANM1 displayed a very similar cross-correlation distribution. The exact same matrix was observed for ANM2, ANM...
Data
Normal mode analysis: GNM and ANM. (DOCX)
Data
Motion type II – ANM5. The ANM5 deformations are viewed as cartoons from the side, with the lumen below. The colors, corresponding to GNM3 (Fig. 5), depict two oppositely correlated dynamical elements, consisting of the lumen- and stroma-facing halves, separated by the hinge at the ring center. The two dynamical elements undergo twisting motions in...
Data
Motion type III – ANM7. The deformations predicted by ANM7 are shown from the side and colored by the cross-correlations of the N-terminal of chain A with the rest of the structure, blue-to-red indicating negative-to-positive correlation. The motion consists of bending and stretching of the structure towards the membrane, affecting the exposure of...
Data
Crystal contacts and packing. The c-ring is viewed in cartoon representation. A. Crystal contacts between the c-ring (blue) and its adjacent symmetry mates (green), with interactions of either the stroma loops or the N- and C- termini. B. Crystal contacts at the hydrophobic region between adjacent rings, mediated by density corresponding to single...
Data
Electron density map of the proton binding site. Side view of the c-ring, with the lumen below. The binding site residues are shown as sticks, with their attributed electron density shown as mesh. Density map (2Fo–Fc), contoured at 1.3σ. (TIF)
Data
Motion type I – ANM1. The deformations of ANM1, matched to the first type of motion, are shown as cartoons and viewed from the lumen. The coloring corresponds to the inter-residue correlation of chain A of GNM1-2, ranging from red to blue (Figs. 4A and 4B). The motion manifests extraction/contraction of the ring emphasized at the lumen end, with op...
Data
Motion type I – ANM3. Same as Movie S1, with ANM3 viewed from the stroma. This shows the extraction/contraction motion manifested at the stroma-facing ends. (MOV)
Article
Micrometer-thick plant photosystem I crystals made of up to 1000 layers of serially arranged protein complexes generate unprecedented high photovoltages when placed on a conducting solid surface and measured using Kelvin probe force microscopy. The successive layers form serially photoinduced dipoles in the crystal that give rise to electric fields...
Article
N. Nelson and co-workers describe on page 2988 micrometre-thick plant photosystem I crystals of up to 1000 layers of serially arranged protein chlorophyll complexes. In these proteins, photosynthesis efficiently converts light to electricity, generating unprecedented photovoltages (>49 V). The crystals are self-assembled from nanometre-sized protei...
Article
Sustainable hydrogen production in cyanobacteria becomes feasible as a result of our recent studies of the structure of photosystem I encoding operon in a marine phage. We demonstrated that the fused PsaJF subunit from the phage, substituted for the two separate subunits in Synechocystis, enabled the mutated PSI to accept electrons from additional...
Article
Cyanobacteria play a key role in marine photosynthesis, which contributes to the global carbon cycle and to the world oxygen supply. Genes encoding the photosystem-II (PSII) reaction centre are found in many cyanophage genomes, and it was suggested that the horizontal transfer of these genes might be involved in increasing phage fitness. Recently,...
Article
Because life on earth is governed by the second law of thermodynamics, it is subject to increasing entropy. Oxygenic photosynthesis, the earth's major producer of both oxygen and organic matter, is a principal player in the development and maintenance of life, and thus results in increased order. The primary steps of oxygenic photosynthesis are dri...
Article
Full-text available
Membrane proteins constitute 20–30% of all proteins encoded by the genome of various organisms. Large amounts of purified proteins are required for activity and crystallization attempts. Thus, there is an unmet need for a heterologous membrane protein overexpression system for purification, crystallization, and activity determination. We developed...
Article
Full-text available
Photosystem I functions as a sunlight energy converter, catalyzing one of the initial steps in driving oxygenic photosynthesis in cyanobacteria, algae, and higher plants. Functionally, Photosystem I captures sunlight and transfers the excitation energy through an intricate and precisely organized antenna system, consisting of a pigment network, to...
Article
Full-text available
Cyanobacteria of the Synechococcus and Prochlorococcus genera are important contributors to photosynthetic productivity in the open oceans. Recently, core photosystem II (PSII) genes were identified in cyanophages and proposed to function in photosynthesis and in increasing viral fitness by supplementing the host production of these proteins. Here...
Article
Full-text available
The life of every eukaryotic cell depends on the function of vacuolar H(+)-ATPase (V-ATPase). Today we know that V-ATPase is vital for many more physiological and biochemical processes than it was expected three decades ago when the enzyme was discovered. These range from a crucial role in the function of internal organelles such as vacuoles, lysos...
Article
Photosystem I (PSI) is a membrane protein complex that catalyzes sunlight-driven transmembrane electron transfer as part of the photosynthetic machinery. Photosynthetic organisms appeared on the Earth about 3.5 billion years ago and provided an essential source of potential energy for the development of life. During the course of evolution, these p...
Article
Full-text available
Hydrogen is one of the most promising energy carriers among environmentally friendly and clean energy sources for the future. If the extremely effective photosynthetic energy conversion could be efficiently combined with a biological process of hydrogen production, it will represent a significant step toward this goal. The best candidate to do the...
Article
Over the past several years, many crystal structures of photosynthetic pigment-protein complexes have been determined, and these have been used extensively to model spectroscopic results obtained on the same proteins in solution. However, the crystal structure is not necessarily identical to the structure of the protein in solution. Here, we studie...
Article
Full-text available
The life of every eukaryotic cell depends on the function of vacuolar H(+)-ATPase (V-ATPase). Because of its complexity and its challenging properties, the study of this enzyme has lagged behind that of its close relative, F-ATPase. We now know that V-ATPase is vital for many more physiological and biochemical processes than anticipated when the en...
Article
Despite its enormous complexity, a plant Photosystem I (PSI) is arguably the most efficient nano-photochemical machine in Nature. It emerged as a homodimeric structure containing several chlorophyll molecules over 3.5 billion years ago, and has perfected its photoelectric properties ever since. The recently determined structure of plant PSI, which...
Article
Membranes of Chlorobium tepidum contain about 35, 45 and 2-10 molecules of menaquinone-7, chlorobium quinone (1'-oxo-menaquinone-7) and of the polar menaquinone (probably 1'-OH-menaquinone-7) per reaction center, respectively. None of these quinones was retained during the isolation of P840-reaction centers beyond the detection limit of about 0.2 q...
Article
There are 3,200,000 amino acid sequences of length 5 (penta-peptides). Statistically, we expect to see a distribution of penta-peptides that is determined by the frequency of the participating amino acids. We show, however, that not only are there thousands of such penta-peptides that are absent from all known proteomes, but many of them are coded...
Article
Full-text available
All higher organisms on Earth receive energy directly or indirectly from oxygenic photosynthesis performed by plants, green algae and cyanobacteria. Photosystem I (PSI) is a supercomplex of a reaction centre and light-harvesting complexes. It generates the most negative redox potential in nature, and thus largely determines the global amount of ent...
Chapter
The recently determined structure of plant photosystem I (PS I) provides the first relatively high-resolution structural model of a supercomplex containing a reaction center and its peripheral antenna. The peripheral antenna of PS I (LHCI) is composed of four gene products (Lhca1–4) that are unique among the chlorophyll a/b binding proteins in thei...
Article
Full-text available
Bioenergetics and physiology of primary pumps have been revitalized by new insights into the mechanism of energizing biomembranes. Structural information is becoming available, and the three-dimensional structure of F-ATPase is being resolved. The growing understanding of the fundamental mechanism of energy coupling may revolutionize our view of bi...
Article
The family of NRAMP metal ion transporters functions in diverse organisms from bacteria to human. NRAMP1 functions in metal transport across the phagosomal membrane of macrophages, and defective NRAMP1 causes sensitivity to several intracellular pathogens. DCT1 (NRAMP2) transport metal ions at the plasma membrane of cells of both the duodenum and i...