Related Experiment Video
Updated: Feb 12, 2026

Improvement of Bacillus subtilis Spore Enumeration and Label Analysis in Flow Cytometry
Published on: June 30, 2023
Crystallization and preliminary X-ray characterization of queD from Bacillus subtilis, an enzyme involved in
1Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. cicmil@uiuc.edu
Abstract:
QueD (previously named ykvK) is one of several enzymes involved in the biosynthesis of the hypermodified nucleoside queuosine. Queuosine is incorporated into tRNA at position 34 of four tRNAs: tRNA(His), tRNA(Asp), tRNA(Asn) and tRNA(Tyr). The crystallization and preliminary X-ray crystallographic studies of queD are described here. The recombinant protein from Bacillus subtilis was overproduced in Escherichia coli and crystallized using the hanging-drop vapor-diffusion method from 25% PEG 600, 100 mM NaCl and sodium citrate buffer pH 5.5 at 291 K. The crystals diffract to 3.6 A resolution and belong to the cubic space group F4(1)32, with unit-cell parameter a = 240.88 A.
Related Concept Videos
Biosynthesis of Lipids
Biosynthesis of Nucleic Acids
Biosynthesis of Polysaccharides
Biosynthesis in Bacteria
X-ray Crystallography
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Enzymes
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...

