Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Neutron diffraction from a microgravity-grown crystal reveals the active site hydrogens of the internal aldimine form of tryptophan synthase

Drago, Victoria N. ; Devos, Juliette M. ; Blakeley, Matthew P. ; Forsyth, V. Trevor LU ; Parks, Jerry M. ; Kovalevsky, Andrey and Mueser, Timothy C. (2024) In Cell Reports Physical Science 5(2).
Abstract

Pyridoxal 5′-phosphate (PLP), the biologically active form of vitamin B6, is an essential cofactor in many biosynthetic pathways. The emergence of PLP-dependent enzymes as drug targets and biocatalysts, such as tryptophan synthase (TS), has underlined the demand to understand PLP-dependent catalysis and reaction specificity. The ability of neutron diffraction to resolve the positions of hydrogen atoms makes it an ideal technique to understand how the electrostatic environment and selective protonation of PLP regulates PLP-dependent activities. Facilitated by microgravity crystallization of TS with the Toledo Crystallization Box, we report the 2.1 Å joint X-ray/neutron (XN) structure of TS with PLP in the internal aldimine... (More)

Pyridoxal 5′-phosphate (PLP), the biologically active form of vitamin B6, is an essential cofactor in many biosynthetic pathways. The emergence of PLP-dependent enzymes as drug targets and biocatalysts, such as tryptophan synthase (TS), has underlined the demand to understand PLP-dependent catalysis and reaction specificity. The ability of neutron diffraction to resolve the positions of hydrogen atoms makes it an ideal technique to understand how the electrostatic environment and selective protonation of PLP regulates PLP-dependent activities. Facilitated by microgravity crystallization of TS with the Toledo Crystallization Box, we report the 2.1 Å joint X-ray/neutron (XN) structure of TS with PLP in the internal aldimine form. Positions of hydrogens were directly determined in both the α- and β-active sites, including PLP cofactor. The joint XN structure thus provides insight into the selective protonation of the internal aldimine and the electrostatic environment of TS necessary to understand the overall catalytic mechanism.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
enzyme mechanism, fold-type II, macromolecular crystallography, microgravity crystallization, neutron crystallography, neutron diffraction, pyridoxal 5’-phosphate
in
Cell Reports Physical Science
volume
5
issue
2
article number
101827
publisher
Cell Press
external identifiers
  • scopus:85185445006
ISSN
2666-3864
DOI
10.1016/j.xcrp.2024.101827
language
English
LU publication?
yes
id
5a668dce-2e83-4cff-a124-5187862a3678
date added to LUP
2024-03-21 16:03:26
date last changed
2024-03-25 09:58:03
@article{5a668dce-2e83-4cff-a124-5187862a3678,
  abstract     = {{<p>Pyridoxal 5′-phosphate (PLP), the biologically active form of vitamin B<sub>6</sub>, is an essential cofactor in many biosynthetic pathways. The emergence of PLP-dependent enzymes as drug targets and biocatalysts, such as tryptophan synthase (TS), has underlined the demand to understand PLP-dependent catalysis and reaction specificity. The ability of neutron diffraction to resolve the positions of hydrogen atoms makes it an ideal technique to understand how the electrostatic environment and selective protonation of PLP regulates PLP-dependent activities. Facilitated by microgravity crystallization of TS with the Toledo Crystallization Box, we report the 2.1 Å joint X-ray/neutron (XN) structure of TS with PLP in the internal aldimine form. Positions of hydrogens were directly determined in both the α- and β-active sites, including PLP cofactor. The joint XN structure thus provides insight into the selective protonation of the internal aldimine and the electrostatic environment of TS necessary to understand the overall catalytic mechanism.</p>}},
  author       = {{Drago, Victoria N. and Devos, Juliette M. and Blakeley, Matthew P. and Forsyth, V. Trevor and Parks, Jerry M. and Kovalevsky, Andrey and Mueser, Timothy C.}},
  issn         = {{2666-3864}},
  keywords     = {{enzyme mechanism; fold-type II; macromolecular crystallography; microgravity crystallization; neutron crystallography; neutron diffraction; pyridoxal 5’-phosphate}},
  language     = {{eng}},
  month        = {{02}},
  number       = {{2}},
  publisher    = {{Cell Press}},
  series       = {{Cell Reports Physical Science}},
  title        = {{Neutron diffraction from a microgravity-grown crystal reveals the active site hydrogens of the internal aldimine form of tryptophan synthase}},
  url          = {{http://dx.doi.org/10.1016/j.xcrp.2024.101827}},
  doi          = {{10.1016/j.xcrp.2024.101827}},
  volume       = {{5}},
  year         = {{2024}},
}