Compact water-window transmission X-ray microscopy.

M Berglund; L Rymell; M Peuker; T Wilhein; H M Hertz

doi:10.1046/j.1365-2818.2000.00675.x

Home/Archive/PubMed

PubMed · 10692130

Compact water-window transmission X-ray microscopy.

M Berglund·L Rymell·M Peuker·T Wilhein·H M Hertz

View original source ↗Export metadata ↓

Abstract

We demonstrate sub-100 nm resolution water-window soft X-ray full-field transmission microscopy with a compact system. The microscope operates at lambda = 3.37 nm and is based on a 100 Hz table-top regenerative debris-free droplet-target laser-plasma X-ray source in combination with normal-incidence multilayer condenser optics for sample illumination. High-spatial-resolution imaging is performed with a 7.3% efficiency nickel zone plate and a 1024 x 1024 pixel CCD detector. Images of dry test samples are recorded with exposure times of a few minutes and show features smaller than 60 nm.

Explore related subjects

Diatoms Lasers Microscopy, Electron Optics and Photonics X-Rays Journal Article Research Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

M Berglund, L Rymell, M Peuker, T Wilhein, H M Hertz. 2000. Compact water-window transmission X-ray microscopy.. https://doi.org/10.1046/j.1365-2818.2000.00675.x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

The 100 Diatom Genomes Project.

One hundred diatom species have been selected for genome and transcriptome sequencing. The 100 Diatom Genomes Project aims to provide a scalable framework for understanding diatom biodiversity, ecology and evolution, and for investigating their use in biotechnology.

Diatoms↗

PubMed2026

Sulfated mannan of diatoms selects host-specific microbiota in the sunlit ocean.

BACKGROUND: Diatoms, a keystone phylum in Earth's ecosystems, are responsible for substantial oxygen production and the fixation of carbon dioxide in the form of carbohydrates that fuel global food webs. They host diverse prokaryotes, yet how diatoms preferentially recruit those with complementary metabolic traits remains unknown. RESULTS: We discovered that diatoms exude a C6-sulfated α-1,3-mannan that serves as a selective carbon source for adapted Polaribacter. Its structure was resolved using NMR spectroscopy, chromatography, chemical synthesis, and enzymatic dissection. Biochemical, physiological, and structural analyses demonstrated, that specialized Bacteroidota employ a four-enzyme pathway to metabolize this glycan. Metagenomic and transcriptomic data revealed that sulfated mannan utilization loci are globally abundant and actively expressed in surface ocean bacterioplankton. Because this mannan provides only carbon, oxygen, sulfur, and hydrogen, bacteria must obtain other essential elements elsewhere, reinforcing metabolic interdependence. CONCLUSIONS: Together, these results define a chemically specific interaction between diatoms and specialized bacteria that is mediated by a single sulfated polysaccharide and a dedicated four-enzyme degradation pathway. Presence of this pathway in marine metagenomes and transcriptomes indicates that a sulfated mannan from diatoms exerts selection pressure in the sunlit ocean microbiome. Video Abstract.

Diatoms↗

PubMed2026

From isolation to insights: mitochondrial complex I in the diatom Phaeodactylum tricornutum.

Diatoms are among the most ecologically successful microalgae, contributing significantly to marine primary production and global carbon cycling. Their distinctive metabolic architecture, shaped by a complex evolutionary history involving secondary endosymbiosis, includes a highly compartmentalized cell organization and unique metabolic pathways. In Phaeodactylum tricornutum, a model pennate diatom, chloroplasts with four membranes and mitochondria of likely exosymbiotic origin exhibit intricate physical and metabolic interactions that support integrated carbon and nitrogen metabolism. The mitochondrial electron transport chain, essential for ATP synthesis, shows clade-specific structural and compositional adaptations. Despite its importance, detailed proteomic characterization has remained limited. Here, we report a method for the isolation of mitochondrial complex I from P. tricornutum and present a comprehensive proteomic analysis. Our results confirm the presence of carbonic anhydrase and bridge modules, both previously proposed as ancestral features of mitochondrial complex I, and identify at least one novel, clade-specific subunit that resembles NAD(P)H-dependent trans-2-enoyl-CoA/ACP reductases (TER) from other species. The subunit is similar to proteins involved in mitochondrial fatty acid biosynthesis. Our findings provide new insights into the composition, evolutionary conservation, and potential biotechnological relevance of this essential respiratory protein complex in diatoms.

Diatoms↗