5561-87-5Relevant articles and documents
Chemical structure of cichorinotoxin, a cyclic lipodepsipeptide that is produced by Pseudomonas cichorii and causes varnish spots on lettuce
Komatsu, Hidekazu,Shirakawa, Takashi,Uchiyama, Takeo,Hoshino, Tsutomu
, p. 299 - 309 (2019/02/20)
Pseudomonas cichorii, which causes varnish spots on lettuce and seriously damages lettuce production during the summer season in the highland areas of Japan (e.g., Nagano and Iwate prefectures) was isolated. The structure of a toxin produced by this organism was analyzed based on the detailed evaluation of its 2D NMR and FABMS spectra, and this compound has not been reported previously. We propose the name cichorinotoxin for this toxin. In conjunction with the D or L configurations of each amino acid, which were determined by Marfey’s method, we propose the structure of cichorinotoxin to be as follows: 3-hydroxydecanoyl-(Z)-dhThr1-D-Pro2-D-Ala3-D-Ala4-D-Ala5-D-Val6-D-Ala7-(Z)-dhThr8-Ala9-Val10-D-Ile11-Ser12-Ala13-Val14-Ala15-Val16-(Z)-dhThr17-D-alloThr18-Ala19-L-Dab20-Ser21-Val22, and an ester linkage is present between D-alloThr18 and Val22 (dhThr: 2-aminobut-2-enoic acid; Dab: 2,4-diaminobutanoic acid). Thus, the toxin is a lipodepsipeptide with 22 amino acids. The mono- and tetraacetate derivatives and two alkaline hydrolysates, compounds A and B, were prepared. We discuss here the structure–activity relationships between the derivatives and their necrotic activities toward lettuce.
Controlling the Regioselectivity of Fatty Acid Hydroxylation (C10) at α- and β-Position by CYP152A1 (P450Bsβ) Variants
Hammerer, Lucas,Friess, Michael,Cerne, Jeyson,Fuchs, Michael,Steinkellner, Georg,Gruber, Karl,Vanhessche, Koenraad,Plocek, Thomas,Winkler, Christoph K.,Kroutil, Wolfgang
, p. 5642 - 5649 (2019/11/03)
Regioselective hydroxylation on inactivated C?H bonds is among the dream reactions of organic chemists. Cytochrome P450 enzymes (CYPs) perform this reaction in general with high regio- and stereoselectivity (e. g. for steroids as substrates). Furthermore, enzyme engineering may allow to tune the properties of the enzyme. Regioselective hydroxylation of shorter or linear molecules (fatty acids), however, remains challenging even with this enzyme class, due to the high similarity of the substrate's backbone carbons and their conformational flexibility. CYPs hydroxylating fatty acids selectively in the chemically more distinct α- or ω- position are well described. In contrast, selective in-chain hydroxylation of fatty acids lacks precedence. The peroxygenase CYP152A1 (P450Bsβ) is a family member that displays fatty acid hydroxylation at both, the α- and β-position, with preference for the α-position. Herein we report the influence of hydrophobic active site residues on the hydroxylation pattern of this enzyme. By site directed mutagenesis and combination of the libraries, double and triple mutation variants were identified, which hydroxylated decanoic acid (C10) with improved regio-selectivity in the β-position. Variants were identified with a 10-fold increase of the β-regioselectivity (expressed as α/β-ratio) compared to the wild type. In total 103 variants of CYP152A1 (P450Bsβ) were investigated.
Erratum: A Continuous, Fluorogenic Sirtuin 2 Deacylase Assay: Substrate Screening and Inhibitor Evaluation (Journal of Medicinal Chemistry (2016) 59 (1021-1031) DOI 10.1021/acs.jmedchem.5b01532)
Galleano, Iacopo,Schiedel, Matthias,Jung, Manfred,Madsen, Andreas S.,Olsen, Christian A.
supporting information, p. 2847 - 2847 (2016/04/10)
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