19526-23-9Relevant articles and documents
Rapid total synthesis of cyclic lipodepsipeptides as a premise to investigate their self-assembly and biological activity
De Vleeschouwer, Matthias,Sinnaeve, Davy,Van Den Begin, Jos,Coenye, Tom,Martins, Jose C.,Madder, Annemieke
, p. 7766 - 7775 (2014)
A rapid and efficient total synthesis is reported for the cyclic lipodepsipeptide pseudodesmin A. This member of the Pseudomonas viscosin group is active against Gram-positive bacteria and features self-assembling properties. A conserved serine residue within the lactone macrocycle is exploited for initial immobilization on 2-chlorotrityl chloride resin through ether formation with the side-chain alcohol. Subsequent elongation proceeds through Fmoc solid-phase peptide synthesis, including automated incorporation of the enantioselectively synthesized (R)-3-hydroxydecanoic acid lipid tail. Following esterification to generate the incipient lactone bond, the macrocycle is formed by on-resin head-to-tail macrolactamization and cleaved from the resin to give the desired compound in good purity. The short and efficient synthesis route allows rapid generation of analogues by facile variation of both the peptide and lipid moieties with good control of epimerization while maximizing automation. Synthesis of the pseudodesmin A enantiomer yields identical self-assembly and biological activity to that observed for the natural compound, showing that activity is not mediated by chiral interactions. A D-Asn8 analogue developed en route retains self-assembly, but loses activity. The synthesis strategy should be generally applicable for the rapid generation of analogues from various cyclic lipodepsipeptide groups, allowing an investigation of their self-assembling properties and structure-activity relationships. Accessing cyclic peptides: An efficient, rapid, high-yielding, and versatile total synthesis of the self-assembling Pseudomonas cyclic lipodepsipeptide pseudodesmin A is presented (see figure). The approach involves solid-phase peptide synthesis with serine side-chain immobilization. The route allows rapid analogue production, unlocking structure-activity relationship studies. The self-assembly and biological activity properties of two analogues are reported, including the enantiomer.
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.
Rhamnolipid inspired lipopeptides effective in preventing adhesion and biofilm formation of Candida albicans
Jovanovic, Milos,Radivojevic, Jelena,O'Connor, Kevin,Blagojevic, Stevan,Begovic, Biljana,Lukic, Vera,Nikodinovic-Runic, Jasmina,Savic, Vladimir
, p. 209 - 217 (2019/03/23)
Rhamnolipids are biodegradable low toxic biosurfactants which exert antimicrobial and anti-biofilm properties. They have attracted much attention recently due to potential applications in areas of bioremediation, therapeutics, cosmetics and agriculture, however, the full potential of these versatile molecules is yet to be explored. Based on the facts that many naturally occurring lipopeptides are potent antimicrobials, our study aimed to explore the potential of replacing rhamnose in rhamnolipids with amino acids thus creating lipopeptides that would mimic or enhance properties of the parent molecule. This would allow not only for more economical and greener production but also, due to the availability of structurally different amino acids, facile manipulation of physico-chemical and biological properties. Our synthetic efforts produced a library of 43 lipopeptides revealing biologically more potent molecules. The structural changes significantly increased, in particular, anti-biofilm properties against Candida albicans, although surface activity of the parent molecule was almost completely abolished. Our findings show that the most active compounds are leucine derivatives of 3-hydroxy acids containing benzylic ester functionality. The SAR study demonstrated a further increase in activity with aliphatic chain elongation. The most promising lipopeptides 15, 23 and 36 at 12.5 μg/mL concentration allowed only 14.3%, 5.1% and 11.2% of biofilm formation, respectively after 24 h. These compounds inhibit biofilm formation by preventing adhesion of C. albicans to abiotic and biotic surfaces.
A Continuous, Fluorogenic Sirtuin 2 Deacylase Assay: Substrate Screening and Inhibitor Evaluation
Galleano, Iacopo,Schiedel, Matthias,Jung, Manfred,Madsen, Andreas S.,Olsen, Christian A.
, p. 1021 - 1031 (2016/02/23)
Sirtuins are important regulators of lysine acylation, which is implicated in cellular metabolism and transcriptional control. This makes the sirtuin class of enzymes interesting targets for development of small molecule probes with pharmaceutical potential. To achieve detailed profiling and kinetic insight regarding sirtuin inhibitors, it is important to have access to efficient assays. In this work, we report readily synthesized fluorogenic substrates enabling enzyme-economical evaluation of SIRT2 inhibitors in a continuous assay format as well as evaluation of the properties of SIRT2 as a long chain deacylase enzyme. Novel enzymatic activities of SIRT2 were thus established in vitro, which warrant further investigation, and two known inhibitors, suramin and SirReal2, were profiled against substrates containing ε-N-acyllysine modifications of varying length.
