Soft X-Ray Imaging of Cellular Carbon and Nitrogen Distributions in Heterocystous Cyanobacteria

Teramoto, Tokuo; Azai, Chihiro; Terauchi, Kazuki; Yoshimura, Masashi; Ohta, Toshiaki

doi:10.1104/pp.17.01767

Cited by 8 publications

(10 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Other nutritional, developmental, or environmental factors may also shape C/N balance and the underlying signaling pathways. As an illustration to this idea, the C/N ratio differs in vegetative cells and heterocysts in Anabaena PCC 7120, with heterocysts accumulating a higher level of nitrogen reserves, consistent with their dedicated function of N2 fixation for the whole filaments [73].…”

Section: C/n Metabolic Balance Through the Integration Of 2-og And 2-pg Signalsmentioning

confidence: 87%

Carbon/Nitrogen Metabolic Balance: Lessons from Cyanobacteria

Zhang

Zhou

Burnap

et al. 2018

Trends in Plant Science

148

View full text Add to dashboard Cite

Carbon and nitrogen are the two most abundant nutrient elements for all living organisms, and their metabolism is tightly coupled. What are the signalling mechanisms that cells use to sense and control the carbon/nitrogen (C/N) metabolic balance following environmental changes? Based on studies in cyanobacteria, it was found that 2-phosphoglycolate derived from photorespiration and 2-oxoglutarate from the Krebs cycle act respectively as the carbonand nitrogen-starvation signals, and their concentration ratio likely reflects the status of the C/N metabolic balance. We will present and discuss the regulatory principles underlying the signalling mechanisms, which are likely to be conserved in other photosynthetic organisms.These concepts may also contribute to developments in the field of biofuel engineering or improvements in crop productivity.

show abstract

Section: C/n Metabolic Balance Through the Integration Of 2-og And 2-pg Signalsmentioning

confidence: 87%

Carbon/Nitrogen Metabolic Balance: Lessons from Cyanobacteria

Zhang

Zhou

Burnap

et al. 2018

Trends in Plant Science

148

View full text Add to dashboard Cite

show abstract

“…Cryo-Soft X-ray Tomography (cryo-SXT) is an X-raybased technique which operates at the 'water-window' (spectral region between the K edges of carbon and oxygen atoms, ca 280-530 eV, where structured carbon-rich biological matter absorbs light significantly more than the surrounding oxygen-rich medium) [25]. This generates natural contrast and allows imaging of the inner structure of cryopreserved whole cells without the need for further contrast through the use of additional chemical staining [26]. Cryo-SXT makes use of samples that have been vitrified, to immobilise and cryo-preserve cell structure, and therefore delivers 3D imaging of hydrated biological samples (cells and thin tissue slices) under near-native conditions at high resolution (in the tens of nanometre range) [27,28].…”

Section: Introductionmentioning

confidence: 99%

X-ray tomography of cryopreserved human prostate cancer cells: mitochondrial targeting by an organoiridium photosensitiser

et al. 2020

View full text Add to dashboard Cite

show abstract

“…In temperate lakes, limited nutrient and in particular Ndeficiency has consensually been shown to support blooms of N-fixing Cyanobacteria [62,63]. This could explain the increased presence of Cyanobacteria in the 9.6 m and 147.9 m samples of Lake Ohrid, along with low C/N ratio [64], since dry and cold conditions during glacial periods likely caused nutrient depletion in Lake Ohrid [4]. However, most cyanobacterial sequences obtained from these intervals could not be affiliated to a given genus, and those that were affiliated mainly belong to Cyanobium, which seems to lack N-fixing genes [65].…”

Section: Impact Of Environmental Parameters On Current Communitiesmentioning

confidence: 99%

Weak influence of paleoenvironmental conditions on the subsurface biosphere of Lake Ohrid in the last 515 ka

Thomas¹,

Vogel²,

Wagner³

et al. 2020

Preprint

View full text Add to dashboard Cite

Understanding the response of geo-and biosystems to past climatic disturbance is primordial to assess the short to long terms effects of current global change. Lacustrine sediments are commonly used to investigate the impact of climatic change on biogeochemical cycling. In these sediments, subsurface microbial communities play a primordial role in nutrient, organic matter and elemental cycling, but they also can affect the sedimentary record and overprint the original paleoenvironmental signal. Subsurface microbial communities have therefore been investigated to assess the potential connection between microbial diversity and environmental change. Lake Ohrid (North Macedonia, Albania) is the oldest lake in Europe and has been the target of a scientific deep drilling in 2013. The upper 447 m of the 584-mlong sedimentary drill core record obtained from the central part of the lake (DEEP site) is composed of clayey to silty-clayey lithologies differing substantially in terms of carbonate and organic matter content between glacials and interglacials. We investigated the microbial diversity in the retrieved sediment using 16S rRNA gene sequences along the upper ca. 200 m of the DEEP site record spanning ca. 515 ka to assess whether subsurface microbial communities were following a similar trend. Results show that Atribacteria, Betaproteobacteria, Bathyarchaeota and to a lower extent Dehalococcoidia phyla structured the community but their occurrence appears to be independent from each other. Atribacteria and Bathyarchaeota together with Dehalococcoidia are commonly encountered in deep lacustrine and marine sediments. Their metabolic versatility is adapted to low energy environments where they can realize the 3 fermentation of various substrates (sugars, propionate and amino acids). The generation of H2 from Atribacteria and other fermenters can be used by Dehalococcoidia and Bathyarchaeota for acetogenesis, and even for chemolithoautrophic processes suggested at greater depths. Betaproteobacteria-associated sequences were often co-occurring with cyanobacterial sequences that suggest preservation of ancient DNA from the water column or catchment, down to at least 340 ka. In particular, fossil DNA from Cyanobacteria in dry glacial intervals may be the relict of ancient blooms of N-fixing clades in periods of nitrogen depletion. We compared the richness and diversity of all phylotypes with environmental parameters measured in corresponding intervals to test for the relationship between paleoenvironmental conditions, climatic modes and the subsurface biosphere. We found no significant relationship between any phylotype and measured environmental parameters, nor with sediment age or climate patterns. Our preliminary results support a weak recording of early diagenetic processes and their actors by bulk prokaryotic sedimentary DNA in Lake Ohrid, which might suggest dominant turnover and replacement by specialized low-energy clades of the deep biosphere.

show abstract

Soft X-Ray Imaging of Cellular Carbon and Nitrogen Distributions in Heterocystous Cyanobacteria

Cited by 8 publications

References 53 publications

Carbon/Nitrogen Metabolic Balance: Lessons from Cyanobacteria

Carbon/Nitrogen Metabolic Balance: Lessons from Cyanobacteria

X-ray tomography of cryopreserved human prostate cancer cells: mitochondrial targeting by an organoiridium photosensitiser

Weak influence of paleoenvironmental conditions on the subsurface biosphere of Lake Ohrid in the last 515 ka

Contact Info

Product

Resources

About