Cryo-XPS spectra from bacterial reference strain Pseudomonas fluorescens DSM50090

Abstract

Cryogenic X-ray Photoelectron Spectroscopy (cryo-XPS) was used to analyze the cell envelope of intact and hydrated Gram-negative bacteria of the species Pseudomonas fluorescens. We used a reference strain, nr DSM50090, from the German microbial culture collection, which we previously have suggested would function well as a reference strain for future XPS analyses of Gram-negative bacteria. Bacteria were grown on nutrient agar plates at room temperature, collected with a cultivation loop and washed using phosphate buffered saline (PBS). An aliquot of the cell pellet was fast-frozen on the sample holder in the sample introduction chamber to a temperature of 103 K and kept frozen throughout the measurement. Survey spectra and highresolution spectra of Na 1s, O 1s, N 1s, C 1s, Cl 2p, S 2p, and P 2p are reported. The spectra obtained from the analyzed cells represent a combined signal from O, N, C and S atoms in proteins, lipids and polysaccharides at the cell surface. Furthermore, signal from P, Na, K and Cl atoms were present both originating from processes in the cell envelope as well as remnants from the wash buffer.

Nucleotide‐Based Carbon Dot‐Assisted Synthesis of High Surface Area Porous α‐Ni(OH)2 as an Efficient Battery‐Type Supercapacitor Electrode

“…The peak at 398.9 eV corresponds to ─N═ group, while the peak at 400.1 eV corresponds to C─NH 2 group. [43] The weak peak at 400.9 eV is due to the presence of HN─C═O group.…”