Neutron diffraction from a microgravity-grown crystal reveals the active site hydrogens of the internal aldimine form of tryptophan synthase
(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.
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- author
- Drago, Victoria N. ; Devos, Juliette M. ; Blakeley, Matthew P. ; Forsyth, V. Trevor LU ; Parks, Jerry M. ; Kovalevsky, Andrey and Mueser, Timothy C.
- organization
- publishing date
- 2024-02-21
- 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
-
- pmid:38645802
- 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
- 2024-07-27 04:15:40
@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}}, }