A5065861786- Photosynthetic Processes and Mechanisms
- Algal biology and biofuel production
- Marine and coastal ecosystems
- Aquatic Ecosystems and Phytoplankton Dynamics
- Biocrusts and Microbial Ecology
- Microbial Community Ecology and Physiology
- Hemoglobin structure and function
- Marine Toxins and Detection Methods
- Protist diversity and phylogeny
- Plant responses to elevated CO2
- Spectroscopy and Quantum Chemical Studies
- Photoreceptor and optogenetics research
- Diatoms and Algae Research
- Lichen and fungal ecology
- Atmospheric and Environmental Gas Dynamics
- Mitochondrial Function and Pathology
- Microbial Fuel Cells and Bioremediation
- Plant Stress Responses and Tolerance
- Microbial Metabolic Engineering and Bioproduction
- Environmental Toxicology and Ecotoxicology
- Genomics and Phylogenetic Studies
- Marine and coastal plant biology
- Methane Hydrates and Related Phenomena
- Microbial bioremediation and biosurfactants
- Plant Water Relations and Carbon Dynamics
Hebrew University of Jerusalem
2014-2025
Central China Normal University
2022
Dartmouth–Hitchcock Medical Center
2022
Invisible Software (United States)
2013
National Library of Israel
2012
Shanghai Institutes for Biological Sciences
2006
University of Rostock
2006
Center for Excellence in Molecular Plant Sciences
2006
Weizmann Institute of Science
2005
Kyoto University
2001
Diatoms, a type of microscopic marine and freshwater alga, dominate the oceans are responsible for about fifth primary productivity on Earth. The complete genome sequence Phaeodactylum tricornutum is reported in this issue, second diatom to be sequenced. Comparisons with Thalassiosira pseudonana, first, reveal that hundreds genes have been acquired by gene transfer from bacteria — or vice versa. Gene appears common during evolution, creating unorthodox combinations including some plants...
Many microorganisms possess inducible mechanisms that concentrate CO2 at the carboxylation site, compensating for relatively low affinity of Rubisco its substrate, and allowing acclimation to a wide range concentrations. The organization carboxysomes in prokaryotes pyrenoids eukaryotes, presence membrane inorganic carbon (Ci) transport, are central concentrating mechanism. multiple Ci transporting systems cyanobacteria has been indicated. Certain genes involved structural organization,...
The external inorganic carbon pool (CO(2) + HCO(3) (-)) was measured in both high and low CO(2)-grown cells of Chlamydomonas reinhardtii, using a silicone oil layer centrifugal filtering technique. average internal pH values were for each cell type [(14)C]dimethyloxazolidinedione, the pools recalculated on free CO(2) basis. These measurements indicated that able to concentrate up 40-fold relation medium. Low differed their photosynthetic affinity CO(2). differences could be most readily...
DNA microarrays bearing nearly all of the genes unicellular cyanobacterium Synechocystis sp PCC 6803 were used to examine temporal program gene expression during acclimation from low high light intensity. A complete pattern is provided a photosynthetic organism changing More than 160 responsive identified and classified into distinct sets. Genes involved in absorption photochemical reactions downregulated within 15 min exposure intensity, whereas those associated with CO2 fixation protection...
Diatoms are unicellular algae responsible for approximately 20% of global carbon fixation. Their evolution by secondary endocytobiosis resulted in a complex cellular structure and metabolism compared to with primary plastids.The whole genome sequence the diatom Phaeodactylum tricornutum has recently been completed. We identified annotated genes enzymes involved carbohydrate pathways based on extensive EST support comparison second diatom, Thalassiosira pseudonana. Protein localization...
Microcystins are cyanobacterial toxins that represent a serious threat to drinking water and recreational lakes worldwide. Here, we show microcystin fulfils an important function within cells of its natural producer Microcystis. The deficient mutant ΔmcyB showed significant changes in the accumulation proteins, including several enzymes Calvin cycle, phycobiliproteins two NADPH-dependent reductases. We have discovered binds number these proteins vivo binding is strongly enhanced under high...
Photorespiratory 2-phosphoglycolate (2PG) metabolism is essential for photosynthesis in higher plants but thought to be superfluous cyanobacteria because of their ability concentrate CO(2) internally and thereby inhibit photorespiration. Here, we show that 3 routes 2PG are present the model cyanobacterium Synechocystis sp. strain PCC 6803. In addition photorespiratory C2 cycle characterized plants, this also possesses bacterial glycerate pathway able completely decarboxylate glyoxylate via...
Cyanobacteria possess a CO(2)-concentrating mechanism that involves active CO(2) uptake and HCO(3)(-) transport. For uptake, we have identified two systems in the cyanobacterium Synechocystis sp. strain PCC 6803, one induced at low constitutive. The CO(2)-induced system showed higher maximal activity affinity for than constitutive system. On basis of speculation separate NAD(P)H dehydrogenase complexes were essential each these systems, reasoned inactivation would allow selection mutants...
INTRODUCTION 45 RECOGNITION OF MEDIATED MEMBRANE TRANSPORT 46 MECHANISMS FOR SUGARS AND AMINO ACIDS 47 Proton Sy mport . .. Oth er Transport M echanis ms 56 TONOPLAST 57 THE NATURE EFFLUX 59 ACCUMULATION RATIO 61 IS EXTERNAL INVERSION SUCROSE RELATED TO ITS UPTAKE? 62 KINETICS 63 Kin etic Models Para met ers for A mino Acid and Sugar Upta ke 67 Int erpretation of Curves Ov Ext ended Conc entration Rang es ....... ,.... 68 SPECIFICITY CARRIERS , 72 Acids ...... .... Sugars ..... 73 PROSPECTS...
Summary Microcystins constitute a serious threat to the quality of drinking water worldwide. These protein phosphatase inhibitors are formed by various cyanobacterial species, including Microcystis sp. produced complex microcystin synthetase, composed peptide synthetases and polyketide synthases, encoded mcyA‐J gene cluster. Recent phylogenetic analysis suggested that synthetase predated metazoan lineage, thus dismissing possibility microcystins emerged as means defence against grazing,...
Dormancy is an important developmental program allowing plants to withstand extended periods of extreme environmental conditions, such as low temperature or drought. Seed dormancy, bud dormancy and desiccation tolerance have been extensively studied, but little known about the mechanisms involved in drought-tolerant plants, key survival many plant species arid semi-arid environments. Subtractive PCR cloning cDNAs from Retama raetam, a C3 legume, revealed that this accompanied by accumulation...
Similarly to the increased number of studies on invasive plants and animals in terrestrial aquatic ecosystems, many reports were recently published invasion Nostocales (cyanobacteria) freshwater environments worldwide. Invasion proliferation new habitats have potential significantly alter structure native community modify ecosystem functioning. But most importantly, they influence water quality due a variety toxic compounds that some species produce. Therefore special attention was given...
Abstract The triple isotope composition (δ 17O and δ 18O) of dissolved O2 in the ocean ice cores was recently used to assess primary productivity over broad spatial temporal scales. However, assessment with aid this method must rely on accurate measurements 17O/16O versus 18O/16O relationship each main oxygen-producing -consuming reactions. Data obtained here showed that cleavage water photosystem II did not fractionate oxygen isotopes; 18O evolved were essentially identical those substrate...
The nature of the inorganic carbon (Ci) species actively taken up by cyanobacteria CO2 or HCO3− has been investigated. kinetics uptake, as well that indicated involvement a saturable process. apparent affinity uptake mechanism for was higher than HCO3−. Though calculated V max same in both cases, maximum rate actually observed when supplied. Ci far more sensitive to carbonic anhydrase inhibitor ethoxyzolamide Observations photosynthetic function intracellular level (following supply 5...
We describe a novel allelopathic interaction whereby the cyanobacterium Microcystis sp. inhibits photosynthesis in freshwater dinoflagellate Peridinium gatunense by abolishing its internal carbonic anhydrase activity. Our analysis indicated positive correlation between winter presence of and timing annual spring bloom Lake Kinneret (Sea Galilee, Israel). severely inhibited growth mixed laboratory cultures. This was attributed to excretion substances rather than successful competition for...