keyword
MENU ▼
Read by QxMD icon Read
search

cyanobacterial

keyword
https://www.readbyqxmd.com/read/29353309/methods-for-enhancing-cyanobacterial-stress-tolerance-to-enable-improved-production-of-biofuels-and-industrially-relevant-chemicals
#1
REVIEW
Rebecca L Kitchener, Amy M Grunden
Cyanobacteria are photosynthetic prokaryotes that can fix atmospheric CO2 and can be engineered to produce industrially important compounds such as alcohols, free fatty acids, alkanes used in next-generation biofuels, and commodity chemicals such as ethylene or farnesene. They can be easily genetically manipulated, have minimal nutrient requirements, and are quite tolerant to abiotic stress making them an appealing alternative to other biofuel-producing microbes which require additional carbon sources and plants which compete with food crops for arable land...
January 20, 2018: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/29345130/two-marine-cyanobacterial-aplysiatoxin-polyketides-neo-debromoaplysiatoxin-a-and-b-with-k-channel-inhibition-activity
#2
Bing-Nan Han, Ting-Ting Liang, Lawrence Jordan Keen, Ting-Ting Fan, Xiao-Dan Zhang, Lin Xu, Qi Zhao, Shu-Ping Wang, Hou-Wen Lin
The isolation and structure elucidation of two cyanobacterial debromoaplysiatoxin (DAT) analogues, neo-debromoaplysiatoxin A (1) and neo-debromoaplysiatoxin B (2), were reported and found to possess 6/10/6 and 6/6/6 fused-ring systems, respectively, which are rarely seen among aplysiatoxins. Both compounds exhibited potent blocking activity against Kv1.5 with IC50 values of 6.94 ± 0.26 and 0.30 ± 0.05 μM, respectively. These findings suggest the potential of aplysiatoxin analogues in modulating ionic channels and also provide links between the DAT target, protein kinase C, and cell regulation...
January 18, 2018: Organic Letters
https://www.readbyqxmd.com/read/29339303/estrogenic-activity-of-cylindrospermopsin-and-anatoxin-a-and-their-oxidative-products-by-feiii-b-h2o2
#3
Jishan Liu, Sandra E Hernández, Simon Swift, Naresh Singhal
The cyanotoxins released into waters during cyanobacterial blooms can pose serious hazards to humans and animals. Apart from their toxicological mechanisms, cyanotoxins have been shown to be involved in estrogenic activity by in vivo and in vitro assays; however, there is limited information on the change in estrogenicity of cyanotoxins following chemical oxidation. In this study, the estrogenic activity of cylindrospermopsin (CYL) and anatoxin-a (ANA) at concentrations ranging from 2.4 × 10-7 M to 2...
January 10, 2018: Water Research
https://www.readbyqxmd.com/read/29335634/the-pii-signaling-protein-from-red-algae-represents-an-evolutionary-link-between-cyanobacterial-and-chloroplastida-pii-proteins
#4
Tatyana Lapina, Khaled A Selim, Karl Forchhammer, Elena Ermilova
PII superfamily consists of widespread signal transduction proteins found in all domains of life. Whereas they are well-studied in Archaea, Bacteria and Chloroplastida, no PII homolog has been analyzed in Rhodophyta (red algae), where PII is encoded by a chloroplast localized glnB gene. Here, we characterized relevant sensory properties of PII from the red alga Porphyra purpurea (PpPII) in comparison to PII proteins from different phyla of oxygenic phototrophs (cyanobacteria, Chlamydomonas and Physcomitrella) to assess evolutionary conservation versus adaptive properties...
January 15, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29335171/effect-of-hydrogen-peroxide-on-microcystic-aeruginosa-role-of-cytochromes-p450
#5
Jia Wang, Zunwei Chen, Hui Chen, Yuezhong Wen
Cyanobacterial bloom has been rising as a worldwide issue owing to its adverse effects to water quality and ecological health. To solve this problem, hydrogen peroxide (H2O2) has been considered as a potential algaecide because no by-products are generated after treatment and because it kills cyanobacteria selectively. In addition, cytochromes P450 (CYPs) was reported to be related with H2O2, but the roles of CYPs in the regulation of H2O2 in cyanobacteria have yet to be investigated. In this study, the CYPs suicide inhibitor 1-aminobenzotriazole (ABT) was added to the representative cyanobacteria Microcystis aeruginosa (M...
January 12, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29331411/tailoring-cyanobacterial-cell-factory-for-improved-industrial-properties
#6
REVIEW
Guodong Luan, Xuefeng Lu
Photosynthetic biomanufacturing provides a promising solution for sustainable production of biofuels and biochemicals. Cyanobacteria are among the most promising microbial platforms for the construction of photosynthetic cell factories. Metabolic engineering of cyanobacteria has enabled effective photosynthetic synthesis of diverse natural or non-natural metabolites, while commercialization of photosynthetic biomanufacturing is usually restricted by process and economic feasibilities. In actual outdoor conditions, active cell growth and product synthesis is restricted to narrow light exposure windows of the day-night cycles and is threatened by diverse physical, chemical, and biological environmental stresses...
January 10, 2018: Biotechnology Advances
https://www.readbyqxmd.com/read/29330710/glycogen-production-in-marine-cyanobacterial-strain-synechococcus-sp-nkbg-15041c
#7
Amr Badary, Shouhei Takamatsu, Mitsuharu Nakajima, Stefano Ferri, Peter Lindblad, Koji Sode
An important feature offered by marine cyanobacterial strains over freshwater strains is the capacity to grow in seawater, replacing the need for often-limited freshwater. However, there are only limited numbers of marine cyanobacteria that are available for genetic manipulation and bioprocess applications. The marine unicellular cyanobacteria Synechococcus sp. strain NKBG 15041c (NKBG15041c) has been extensively studied. Recombinant DNA technologies are available for this strain, and its genomic information has been elucidated...
January 12, 2018: Marine Biotechnology
https://www.readbyqxmd.com/read/29328062/cyanobacterial-photosynthesis-under-sulfidic-conditions-insights-from-the-isolate-leptolyngbya-sp-strain-hensonii
#8
Trinity L Hamilton, Judith M Klatt, Dirk de Beer, Jennifer L Macalady
We report the isolation of a pinnacle-forming cyanobacterium isolated from a microbial mat covering the sediment surface at Little Salt Spring-a flooded sinkhole in Florida with a perennially microoxic and sulfidic water column. The draft genome of the isolate encodes all of the enzymatic machinery necessary for both oxygenic and anoxygenic photosynthesis, as well as genes for methylating hopanoids at the C-2 position. The physiological response of the isolate to H2S is complex: (i) no induction time is necessary for anoxygenic photosynthesis; (ii) rates of anoxygenic photosynthesis are regulated by both H2S and irradiance; (iii) O2 production is inhibited by H2S concentrations as low as 1 μM and the recovery rate of oxygenic photosynthesis is dependent on irradiance; (iv) under the optimal light conditions for oxygenic photosynthesis, rates of anoxygenic photosynthesis are nearly double those of oxygenic photosynthesis...
January 12, 2018: ISME Journal
https://www.readbyqxmd.com/read/29324791/sediment-biomarkers-elucidate-the-holocene-ontogeny-of-a-shallow-lake
#9
T E Arnold, W F Kenney, J H Curtis, T S Bianchi, M Brenner
We carried out geochemical analyses on a sediment core from Lake Harris, Florida (USA) to identify sources of organic matter to the sediment throughout the Holocene, and relate changes in those sources to shifts in past climate and environmental conditions. We hypothesized that the sources of organic matter changed in response to regional hydrologic shifts following de-glaciation, and to human population expansion in the state during the 20th century. Hydroclimate shifts in Florida were related to: 1) a steady rise in relative sea level and the fresh water table that began in the early Holocene, 2) wetland formation and expansion ca...
2018: PloS One
https://www.readbyqxmd.com/read/29324646/analysis-of-microcystins-in-cyanobacterial-blooms-from-freshwater-bodies-in-england
#10
Andrew D Turner, Monika Dhanji-Rapkova, Alison O'Neill, Lewis Coates, Adam Lewis, Katy Lewis
Cyanobacterial blooms in freshwater bodies in England are currently monitored reactively, with samples containing more than 20,000 cells/mL of potentially toxin-producing species by light microscopy resulting in action by the water body owner. Whilst significantly reducing the risk of microcystin exposure, there is little data describing the levels of these toxins present in cyanobacterial blooms. This study focused on the quantitative LC-MS/MS analysis of microcystins in freshwater samples, collected across England during 2016 and found to contain potentially toxin-producing cyanobacteria...
January 11, 2018: Toxins
https://www.readbyqxmd.com/read/29324383/the-influence-of-algal-organic-matter-produced-by-microcystis-aeruginosa-on-coagulation-ultrafiltration-treatment-of-natural-organic-matter
#11
Jie Xu, Yanxia Zhao, Baoyu Gao, Songlin Han, Qian Zhao, Xiaoli Liu
Cyanobacterial bloom causes the release of algal organic matter (AOM), which inevitably affects the treatment processes of natural organic matter (NOM). This study works on treating micro-polluted surface water (SW) by emerging coagulant, namely titanium sulfate (Ti(SO4)2), followed by Low Pressure Ultrafiltration (LPUF) technology. In particular, we explored the respective influence of extracellular organic matter (EOM) and intracellular organic matter (IOM) on synergetic EOM-NOM/IOM-NOM removal, functional mechanisms and subsequent filtration performance...
January 5, 2018: Chemosphere
https://www.readbyqxmd.com/read/29324084/protein-association-of-%C3%AE-n-methylamino-l-alanine-in-triticum-aestivum-via-irrigation
#12
Valeska Contardo-Jara, Torsten Schwanemann, Maranda Esterhuizen-Londt, Stephan Pflugmacher
Bioaccumulation of several cyanotoxins has been observed in numerous food webs. More recently, the neurotoxic, non-proteinogenic amino acid β-N-methylamino-L-alanine (BMAA) was shown to biomagnify in marine food webs. It was thus necessary to assess whether a human exposure risk via a terrestrial food source could exist. As shown for other cyanotoxins, spray irrigation of crop plants with cyanobacterial bloom-contaminated surface water poses the risk of toxin transfer into edible plant parts. Therefore, in the present study, we evaluated a possible transfer of BMAA via spray irrigation into the seeds of one of the world's most widely cultivated crop plants, Triticum aestivum...
January 11, 2018: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/29322483/structural-integrity-of-synechocystis-sp-pcc-6803-phycobilisomes-evaluated-by-means-of-differential-scanning-calorimetry
#13
Nia Petrova, Svetla Todinova, Hajnalka Laczko-Dobos, Tomas Zakar, Sindhujaa Vajravel, Stefka Taneva, Zoltan Gombos, Sashka Krumova
Phycobilisomes (PBSs) are supramolecular pigment-protein complexes that serve as light-harvesting antennae in cyanobacteria. They are built up by phycobiliproteins assembled into allophycocyanin core cylinders (ensuring the physical interaction with the photosystems) and phycocyanin rods (protruding from the cores and having light-harvesting function), the whole PBSs structure being maintained by linker proteins. PBSs play major role in light-harvesting optimization in cyanobacteria; therefore, the characterization of their structural integrity in intact cells is of great importance...
January 10, 2018: Photosynthesis Research
https://www.readbyqxmd.com/read/29320853/high-co2-requirement-as-a-mechanism-for-the-containment-of-genetically-modified-cyanobacteria
#14
Ryan L Clark, Gina C Gordon, Nathaniel R Bennett, Haoxiang Lyu, Thatcher W Root, Brian F Pfleger
As researchers engineer cyanobacteria for biotechnological applications, we must consider potential environmental release of these organisms. Previous theoretical work has considered cyanobacterial containment through elimination of the CO2-concentrating mechanism (CCM) to impose a high-CO2 requirement (HCR), which could be provided in the cultivation environment but not in the surroundings. In this work, we experimentally implemented an HCR containment mechanism in Synechococcus sp. PCC7002 (PCC7002) through deletion of carboxysome shell proteins and showed that this mechanism contained cyanobacteria in a 5% CO2 environment...
January 10, 2018: ACS Synthetic Biology
https://www.readbyqxmd.com/read/29318763/mineralisation-of-filamentous-cyanobacteria-in-lake-thetis-stromatolites-western-australia
#15
D Wacey, L Urosevic, M Saunders, A D George
Stromatolites are cited as some of the earliest evidence for life on Earth, but problems remain in reconciling the paucity of microfossils in ancient carbonate examples with the abundance of microbes that help construct modern analogues. Here, we trace the mineralisation pathway of filamentous cyanobacteria within stromatolites from Lake Thetis, Western Australia, providing new insights into microfossil preservation in carbonate stromatolites. Lake Thetis cyanobacteria exhibit a spectrum of mineralisation processes that include early precipitation of Mg-silicates, largely controlled by the morphochemical features of the cyanobacteria, followed by aragonite formation that is inferred to be driven by heterotrophic activity...
January 10, 2018: Geobiology
https://www.readbyqxmd.com/read/29318299/discrimination-between-synechocystis-members-cyanobacteria-based-on-heterogeneity-of-their-16s-rrna-and-its-regions
#16
Mojca Juteršek, Marina Klemenčič, Marko Dolinar
Cyanobacteria are an important group of microorganisms displaying a range of morphologies that enable phenotypic differentiation between the major lineages of cyanobacteria, often to the genus level, but rarely to species or strain level. We focused on the unicellular genus Synechocystis that includes the model cyanobacterial strain PCC 6803. For 11 Synechocystis members obtained from cell culture collections, we sequenced the variable part of the 16S rRNA-encoding region and the 16S - 23S internally transcribed spacer (ITS), both standardly used in taxonomy...
December 2017: Acta Chimica Slovenica
https://www.readbyqxmd.com/read/29315587/comparisons-of-electron-transfer-reactions-in-a-cyanobacterial-tetrameric-and-trimeric-photosystem-i-complexes
#17
Ivan V Shelaev, Mahir D Mamedov, Fedor E Gostev, Arseny V Aybush, Meng Li, Jonathan Nguyen, Barry D Bruce, Victor A Nadtochenko
Photosystem I (PSI) is a Type-I reaction center and the largest photosynthetic complex to be characterized. In cyanobacteria, PSI is organized as a trimer with a three-fold axis of symmetry. Recently, a tetrameric form of PSI has been identified in cyanobacteria. Plastids in plants and algae only contain monomeric PSI, suggesting that tetrameric PSI may be key in the transition from ancestral cyanobacterial trimeric PSI to plant/algal monomeric PSI. We have investigated the kinetics of e- transfer to the initial acceptor in PSI tetramer isolated from Chroococcidiopsis TS-821...
January 8, 2018: Photochemistry and Photobiology
https://www.readbyqxmd.com/read/29315517/role-of-respiratory-terminal-oxidases-in-the-extracellular-electron-transfer-ability-of-cyanobacteria
#18
Narendran Sekar, Jian Wang, Yan Zhou, Yi Fang, Yajun Yan, Ramaraja P Ramasamy
Cyanobacteria are used as anode catalysts in photo-bioelectrochemical cells to generate electricity in a sustainable, economic and environmental friendly manner using only water and sunlight. Though cyanobacteria (CB) possess unique advantage for solar energy conversion by virtue of its robust photosynthesis, they cannot efficiently perform extracellular electron transfer (EET). The reasons being, unlike dissimilatory metal reducing bacteria (that are usually exploited in microbial fuel cells to generate electricity), (1) CB do not possess any special features on their outer membrane to carry out EET and (2) the electrons generated in photosynthetic electron transport chain are channeled into competing respiratory pathways rather than to the anode...
January 8, 2018: Biotechnology and Bioengineering
https://www.readbyqxmd.com/read/29315309/climate-change-could-drive-marine-food-web-collapse-through-altered-trophic-flows-and-cyanobacterial-proliferation
#19
Hadayet Ullah, Ivan Nagelkerken, Silvan U Goldenberg, Damien A Fordham
Global warming and ocean acidification are forecast to exert significant impacts on marine ecosystems worldwide. However, most of these projections are based on ecological proxies or experiments on single species or simplified food webs. How energy fluxes are likely to change in marine food webs in response to future climates remains unclear, hampering forecasts of ecosystem functioning. Using a sophisticated mesocosm experiment, we model energy flows through a species-rich multilevel food web, with live habitats, natural abiotic variability, and the potential for intra- and intergenerational adaptation...
January 2018: PLoS Biology
https://www.readbyqxmd.com/read/29306393/seasonal-dynamics-of-microcystin-degrading-bacteria-and-toxic-cyanobacterial-blooms-interaction-and-influence-of-abiotic-factors
#20
María Ángeles Lezcano, Antonio Quesada, Rehab El-Shehawy
Massive proliferations of cyanobacteria coexist and have different interactions with other microorganisms, including microcystin (MC)-degrading bacteria. Despite their relevance in the environment for the removal of MCs, this bacterial community has been scarcely studied. The influence of physicochemical factors and the seasonal dynamics of toxic cyanobacteria on the relative abundance and seasonal dynamics of the MC-degrading bacterial community with mlr genes (mlr+) were investigated during a two-year study at a water reservoir in central Spain...
January 2018: Harmful Algae
keyword
keyword
59428
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"