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Abstract We report the recombinant preparation fromEscherichia colicells of samples of two closely related, small, secreted cysteine‐rich plant peptides: rapid alkalinization factor 1 (RALF1) and rapid alkalinization factor 8 (RALF8). Purified samples of the native sequence of RALF8 exhibited well‐resolved nuclear magnetic resonance (NMR) spectra and also biological activity through interaction with a plant receptor kinase, cytoplasmic calcium mobilization, andin vivoroot growth suppression. By contrast, RALF1 could only be isolated from inclusion bodies as a construct containing an N‐terminal His‐tag; its poorly resolved NMR spectrum was indicative of aggregation. We prepared samples of the RALF8 peptide labeled with15N and13C for NMR analysis and obtained near complete1H,13C, and15N NMR assignments; determined the disulfide pairing of its four cysteine residues; and examined its solution structure. RALF8 is mostly disordered except for the two loops spanned by each of its two disulfide bridges.
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Calculated and experimental 1 H and 13 C NMR assignments for cannabicitran
Abstract Cannabicitran is an important cannabinoid natural product produced byCannabis sativaand is often found at surprisingly high levels (up to ~10%) in “purified” commercial cannabidiol (CBD) extract preparations. Despite the prevalence of this molecule in CBD oil and other cannabinoid‐related products, and the rapidly expanding interest in cannabinoids for treatment of a wide range of physiological conditions, only unassigned1H NMR data and partial unambiguous13C assignments have been published. Herein, we report the complete1H and13C NMR assignments of cannabicitran and comparatively evaluate the performance of several density functional theory (DFT) methods with varying levels of theory for the calculation of NMR chemical shifts.
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- Award ID(s):
- 2116395
- PAR ID:
- 10361789
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Magnetic Resonance in Chemistry
- Volume:
- 60
- Issue:
- 2
- ISSN:
- 0749-1581
- Page Range / eLocation ID:
- p. 196-202
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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