Open Access19F NMR relaxation studies of fluorosubstituted tryptophans
Author(s) -
Manman Lu,
Rieko Ishima,
Tatyana Polenova
Publication year - 2019
Publication title -
journal of biomolecular nmr
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.346
H-Index - 106
eISSN - 1573-5001
pISSN - 0925-2738
DOI - 10.1007/s10858-019-00268-y
Subject(s) - chemistry , relaxation (psychology) , fluorine 19 nmr , tryptophan , indole test , moiety , context (archaeology) , protein dynamics , ring (chemistry) , cyclophilin , amino acid , computational chemistry , crystallography , stereochemistry , nuclear magnetic resonance spectroscopy , organic chemistry , molecular dynamics , biochemistry , psychology , social psychology , paleontology , gene , biology
We present 19 F longitudinal and transverse relaxation studies for four differently fluorosubstituted L-tryptophans, which carry single F atoms in the indole ring, both in the context of the free amino acid and when located in the cyclophilin A protein. For the free 4F-, 5F-, 6F-, 7F-L-Trp, satisfactory agreement between experimentally measured and calculated relaxation rates was obtained, suggesting that the parameters used for calculating the rates for the indole frame are sufficiently accurate. We also measured and calculated relaxation rates for four differently 19 F-tryptophan labeled cyclophilin A proteins, transferring the parameters from the free amino acid to the protein-bound moiety. Our results suggest that 19 F relaxation data of the large and rigid indole ring in Trp are only moderately affected by protein motions and provide critical reference points for evaluating fluorine NMR relaxation in the future, especially in fluorotryptophan labeled proteins.