Masi M

References (4)

Title : Isolation and Biological Characterization of Homoisoflavanoids and the Alkylamide N-p-Coumaroyltyramine from Crinum biflorum Rottb., an Amaryllidaceae Species Collected in Senegal - Masi_2021_Biomolecules_11_
Author(s) : Masi M , Koirala M , Delicato A , Di Lecce R , Merindol N , Ka S , Seck M , Tuzi A , Desgagne-Penix I , Calabr V , Evidente A
Ref : Biomolecules , 11 : , 2021
Abstract : Crinum biflorum Rottb. (syn. Crinum distichum) is an Amaryllidaceae plant used in African traditional medicine but very few studies have been performed on this species from a chemical and applicative point of view. Bulbs of C. biflorum, collected in Senegal, were extracted with ethanol by Soxhlet and the corresponding organic extract was purified using chromatographic methods. The pure compounds were chemically characterized by spectroscopic techniques (1D and 2D (1)H and (13)C NMR, HR MS and ECD) and X-ray analysis. Four homoisoflavonoids (1-4) and one alkylamide (5) were isolated and characterized as 5,6,7-trimethoxy-3-(4-hydroxybenzyl)chroman-4-one (1), as 3-hydroxy-5,6,7-trimethoxy-3-(4-hydroxybenzyl)chroman-4-one (2), as 3-hydroxy-5,6,7-trimethoxy-3-(4-methoxybenzyl)chroman-4-one (3) and as 5,6,7-trimethoxy-3-(4-methoxybenzyl)chroman-4-one (4), and the alkylamide as (E)-N-(4-hydroxyphenethyl)-3-(4-hydroxyphenyl)acrylamide (5), commonly named N-p-coumaroyltyramine. The relative configuration of compound 1 was verified thanks to the X-ray analysis which also allowed us to confirm its racemic nature. The absolute configurations of compounds 2 and 3 were assigned by comparing their ECD spectra with those previously reported for urgineanins A and B. Flavanoids 1, 3 and 4 showed promising anticancer properties being cytotoxic at low micromolar concentrations towards HeLa and A431 human cancer cell lines. The N-p-coumaroyltyramine (5) was selectively toxic to A431 and HeLa cancer cells while it protected immortalized HaCaT cells against oxidative stress induced by hydrogen peroxide. Compounds 1-4 also inhibited acetylcholinesterase activity with compound 3 being the most potent. The anti-amylase and the strong anti-glucosidase activity of compound 5 were confirmed. Our results show that C. biflorum produces compounds of therapeutic interest with anti-diabetic, anti-tumoral and anti-acetylcholinesterase properties.
ESTHER : Masi_2021_Biomolecules_11_
PubMedSearch : Masi_2021_Biomolecules_11_
PubMedID: 34572511

Title : The C-terminal domain of Corynebacterium glutamicum mycoloyltransferase A is composed of five repeated motifs involved in cell wall binding and stability - Dietrich_2020_Mol.Microbiol__
Author(s) : Dietrich C , Li de la Sierra-Gallay I , Masi M , Girard E , Dautin N , Constantinesco-Becker F , Tropis M , Daffe M , van Tilbeurgh H , Bayan N
Ref : Molecular Microbiology , : , 2020
Abstract : The genomes of Corynebacteriales contain several genes encoding mycoloyltransferases (Myt) that are specific cell envelope enzymes essential for the biogenesis of the outer membrane. MytA is a major mycoloyltransferase of Corynebacterium glutamicum, displaying an N-terminal domain with esterase activity and a C-terminal extension containing a conserved repeated LGFP sequence motif of unknown function. This motif is highly conserved in Corynebacteriales and found associated with cell wall hydrolases and with proteins of unknown function. In this study, we determined the crystal structure of MytA and found that its C-terminal domain is composed of five LGFP motifs and forms a long stalk perpendicular to the N-terminal catalytic alpha/beta-hydrolase domain. The LGFP motifs are composed of a 4-stranded beta-fold and occupy alternating orientations along the axis of the stalk. Multiple acetate binding pockets were identified in the stalk, which could correspond to putative ligand binding sites. By using various MytA mutants and complementary in vitro and in vivo approaches, we provide evidence that the C-terminal LGFP domain interacts with the cell wall peptidoglycan-arabinogalactan polymer. We also show that the C-terminal LGFP domain is not required for the activity of MytA but rather contributes to the overall integrity of the cell envelope.
ESTHER : Dietrich_2020_Mol.Microbiol__
PubMedSearch : Dietrich_2020_Mol.Microbiol__
PubMedID: 32073722
Gene_locus related to this paper: corgl-csp1

Title : Gigantelline, gigantellinine and gigancrinine, cherylline- and crinine-type alkaloids isolated from Crinum jagus with anti-acetylcholinesterase activity - Ka_2020_Phytochemistry_175_112390
Author(s) : Ka S , Masi M , Merindol N , Di Lecce R , Plourde MB , Seck M , Gorecki M , Pescitelli G , Desgagne-Penix I , Evidente A
Ref : Phytochemistry , 175 :112390 , 2020
Abstract : Three undescribed Amarylidaceae alkaloids, named gigantelline, gigantellinine and gigancrinine, were isolated from Crinum jagus (syn.=Crinum giganteum) collected in Senegal, together with the already known sanguinine, cherylline, lycorine, crinine, flexinine and the isoquinolinone derivative hippadine. Gigantelline, gigantellinine and gigancrinine were characterized as 4-(6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydro-isoquinolin-4-yl)-phenol, its 7-O-demethyl-5-hydroxy-4-methoxy derivative and 5,6a,7,7a,8a,9-hexahydro-6,9a-ethano[1,3]dioxolo[4,5-j]oxireno[2,3-b]phenanthridi n-9-ol, respectively, by using spectroscopic (1D and 2D (1)H and (13)C NMR and HRESIMS) and chemical methods. Their relative configuration was assigned by NOESY NMR spectra and NMR calculations, while the absolute configuration was assigned using electronic circular dichroism (ECD) experiments and calculations. Sanguinine, cherylline, crinine, flexinine, and the isoquinolinone hippadine, were isolated for the first time from C. jagus. Cherylline, gigantellinine, crinine, flexinine and sanguinine inhibited the activity of AChE in a dose-dependent manner, and inhibition by sanguinine was remarkably effective (IC50=1.83+/-0.01muM). Cherylline and hippadine showed weak cytotoxicity at 100muM.
ESTHER : Ka_2020_Phytochemistry_175_112390
PubMedSearch : Ka_2020_Phytochemistry_175_112390
PubMedID: 32335411

Title : Amaryllidaceae alkaloids: Absolute configuration and biological activity - Cimmino_2017_Chirality_29_486
Author(s) : Cimmino A , Masi M , Evidente M , Superchi S , Evidente A
Ref : Chirality , 29 :486 , 2017
Abstract : Plants belonging to the Amaryllidaceae family are well known for their ornamental and medicinal use. Plant members of this group are distributed through both tropical and subtropical regions of the world and are dominant in Andean South America, the Mediterranean basin, and southern Africa. Amaryllidaceae plants have been demonstrated to be a good source of alkaloids with a large spectrum of biological activities, the latter being strictly related to the absolute stereochemistry of the alkaloid scaffold. Among them, great importance for practical applications in medicine has galanthamine, which has already spawned an Alzheimer's prescription drug as a potent and selective inhibitor of the enzyme acetylcholinesterase. Furthermore, lycorine as well as its related isocarbostyryl analogs narciclasine and pancratistatine have shown a strong anticancer activity in vitro against different solid tumors with malignant prognosis. This review addresses the assignment of the absolute configuration of several Amaryllidaceae alkaloids and its relationship with their biological activities.
ESTHER : Cimmino_2017_Chirality_29_486
PubMedSearch : Cimmino_2017_Chirality_29_486
PubMedID: 28649696