Point V

References (15)

Title : Direct capture, inhibition and crystal structure of HsaD (Rv3569c) from M. tuberculosis - Barelier_2022_FEBS.J__
Author(s) : Barelier S , Avellan R , Gnawali GR , Fourquet P , Roig-Zamboni V , Poncin I , Point V , Bourne Y , Audebert S , Camoin L , Spilling CD , Canaan S , Cavalier JF , Sulzenbacher G
Ref : Febs J , : , 2022
Abstract : A hallmark of Mycobacterium tuberculosis (M. tb), the aetiologic agent of tuberculosis, is its ability to metabolise host-derived lipids. However, the enzymes and mechanisms underlying such metabolism are still largely unknown. We previously reported that the Cyclophostin & Cyclipostins (CyC) analogues, a new family of potent antimycobacterial molecules, react specifically and covalently with (Ser/Cys)-based enzymes mostly involved in bacterial lipid metabolism. Here, we report the synthesis of new CyC alkyne-containing inhibitors (CyC(yne) ) and their use for the direct fishing of target proteins in M. tb culture via bio-orthogonal click-chemistry activity-based protein profiling (CC-ABPP). This approach led to the capture and identification of a variety of enzymes, and many of them involved in lipid or steroid metabolisms. One of the captured enzymes, HsaD (Rv3569c), is required for the survival of M. tb within macrophages and is thus a potential therapeutic target. This prompted us to further explore and validate, through a combination of biochemical and structural approaches, the specificity of HsaD inhibition by the CyC analogues. We confirmed that the CyC bind covalently to the catalytic Ser(114) residue, leading to a total loss of enzyme activity. These data were supported by the X-ray structures of four HsaD-CyC complexes, obtained at resolutions between 1.6 and 2.6 . The identification of mycobacterial enzymes directly captured by the CyC(yne) probes through CC-ABPP paves the way to better understand and potentially target key players at crucial stages of the bacilli life cycle.
ESTHER : Barelier_2022_FEBS.J__
PubMedSearch : Barelier_2022_FEBS.J__
PubMedID: 36197115
Gene_locus related to this paper: myctu-Rv3569c

Title : Dissecting the membrane lipid binding properties and lipase activity of Mycobacterium tuberculosis LipY domains - Santucci_2019_Febs.j_286_3164
Author(s) : Santucci P , Smichi N , Diomande S , Poncin I , Point V , Gaussier H , Cavalier JF , Kremer L , Canaan S
Ref : Febs J , 286 :3164 , 2019
Abstract : The Mycobacterium tuberculosis LipY protein, a prototype of the proline-glutamic acid (PE) family, exhibits a triacylglycerol (TAG) hydrolase activity that contributes to host cell lipid degradation and persistence of the bacilli. LipY is found either as a full-length intracytosolic form or as a mature extracellular form lacking the N-terminal PE domain. Even though the contribution of the extracellular form in TAG consumption has been partly elucidated, very little information is available regarding the potential interactions of either full-length LipY with the cytoplasmic membrane, or mature form LipY with the outer membrane. Herein, several LipY variants truncated in their N-terminal domain were produced and biochemically characterized in lipid-protein interaction assays, using the monomolecular film technique and FTIR. Comparison of the catalytic activities of these recombinant proteins showed that LipYdelta149, corresponding to the extracellular form of LipY lacking the PE domain, is more active than the full-length protein. This confirms previous studies reporting that the PE domain negatively modulates the TAG hydrolase activity of LipY. Lipid-protein interaction studies indicate that the PE domain anchors LipY onto membrane lipids. Consistent with these findings, we show that LipYdelta149 is loosely associated with the mycobacterial cell wall, and that this interaction is mediated by the sole lipase domain. Overall, our results bring new information regarding the molecular mechanisms by which LipY either binds and hydrolyses host cell lipids or degrades TAG, the major source of lipids within mycobacterial intracytosolic lipid inclusions.
ESTHER : Santucci_2019_Febs.j_286_3164
PubMedSearch : Santucci_2019_Febs.j_286_3164
PubMedID: 31034693
Gene_locus related to this paper: myctu-Rv3097c

Title : Studying Gastric Lipase Adsorption Onto Phospholipid Monolayers by Surface Tensiometry, Ellipsometry, and Atomic Force Microscopy - Benarouche_2017_Methods.Enzymol_583_255
Author(s) : Benarouche A , Sams L , Bourlieu C , Vie V , Point V , Cavalier JF , Carriere F
Ref : Methods Enzymol , 583 :255 , 2017
Abstract : The access to kinetic parameters of lipolytic enzyme adsorption onto lipids is essential for a better understanding of the overall catalytic process carried out by these interfacial enzymes. Gastric lipase, for instance, shows an apparent optimum activity on triglycerides (TAG) at acidic pH, which is controlled by its pH-dependent adsorption at lipid-water interfaces. Since gastric lipase acts on TAG droplets covered by phospholipids, but does not hydrolyze these lipids, phospholipid monolayers spread at the air-water interfaces can be used as biomimetic interfaces to study lipase adsorption and penetration through the phospholipid layer, independently from the catalytic activity. The adsorption of recombinant dog gastric lipase (rDGL) onto 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) monolayers can be monitored by surface tensiometry at various enzyme concentrations, pHs, and surface pressures (Pi). These experimental data and the use of Langmuir adsorption isotherm and Verger-de Haas' lipase kinetics models further allow estimating various parameters including the adsorption equilibrium constant (KAds), the interfacial concentration [Formula: see text] , the molar fraction [Formula: see text] (PhiE*(%), mol%), and the molecular area [Formula: see text] of rDGL adsorbed onto the DLPC monolayer under various conditions. Additional insight into rDGL adsorption/insertion on phospholipid monolayers can be obtained by combining ellipsometry, Langmuir-Blodgett film transfer, and atomic force microscopy. When using multicomponent phospholipid monolayers with phase separation, these techniques allow to visualizing how rDGL preferentially partitions toward liquid expanded phase and at phase boundaries, gets adsorbed at various levels of insertion and impacts on the lateral organization of lipids.
ESTHER : Benarouche_2017_Methods.Enzymol_583_255
PubMedSearch : Benarouche_2017_Methods.Enzymol_583_255
PubMedID: 28063494

Title : New lipase assay using Pomegranate oil coating in microtiter plates - Ulker_2016_Biochimie_120_110
Author(s) : Ulker S , Placidi C , Point V , Gadenne B , Serveau-Avesque C , Canaan S , Carriere F , Cavalier JF
Ref : Biochimie , 120 :110 , 2016
Abstract : Lipases play various roles in fat digestion, lipoprotein metabolism, and in the mobilization of fat stored in lipid bodies in animals, plants and microorganisms. In association with these physiological functions, there is an important field of research for discovering lipase inhibitors and developing new treatments of diseases such as obesity, atherosclerosis, diabetes and tuberculosis. In this context, the development of convenient, specific and sensitive analytical methods for the detection and assay of lipases and/or lipase inhibitors is of major importance. It is shown here that purified triacylglycerols (TAGs) from Punica granatum (Pomegranate) seed oil coated on microtiter plates can be used for the continuous assay of lipase activity by recording the variations with time of the UV absorption spectra at 275 nm. UV absorption is due the release of punicic acid (9Z,11E,13Z-octadeca-9,11,13-trienoic acid), a conjugated triene contained in Pomegranate oil. This new microtiter plate assay allows to accurately measure the activity of a wider range of lipases compared to the similar assay previously developed with Tung oil containing alpha-eleostearic acid (9Z,11E,13E-octadeca-9,11,13-trienoic acid), including the LipY lipase from Mycobacterium tuberculosis. Although punicic acid is a diastereoisomer of alpha-eleostearic acid, the Delta(13)cis double bound found in punicic acid gives a different structure to the acyl chain that probably favours the interaction of Pomegranate TAGs with the lipase active site. The microplate lipase assay using Pomegranate TAGs shows high sensitivity, reproducibility and remarkable relevance for the high-speed screening of lipases and/or lipase inhibitors directly from raw culture media without any purification step.
ESTHER : Ulker_2016_Biochimie_120_110
PubMedSearch : Ulker_2016_Biochimie_120_110
PubMedID: 26343557

Title : Slowing down fat digestion and absorption by an oxadiazolone inhibitor targeting selectively gastric lipolysis - Point_2016_Eur.J.Med.Chem_123_834
Author(s) : Point V , Benarouche A , Zarrillo J , Guy A , Magnez R , Fonseca L , Raux B , Leclaire J , Buono G , Fotiadu F , Durand T , Carriere F , Vaysse C , Couedelo L , Cavalier JF
Ref : Eur Journal of Medicinal Chemistry , 123 :834 , 2016
Abstract : Based on a previous study and in silico molecular docking experiments, we have designed and synthesized a new series of ten 5-Alkoxy-N-3-(3-PhenoxyPhenyl)-1,3,4-Oxadiazol-2(3H)-one derivatives (RmPPOX). These molecules were further evaluated as selective and potent inhibitors of mammalian digestive lipases: purified dog gastric lipase (DGL) and guinea pig pancreatic lipase related protein 2 (GPLRP2), as well as porcine (PPL) and human (HPL) pancreatic lipases contained in porcine pancreatic extracts (PPE) and human pancreatic juices (HPJ), respectively. These compounds were found to strongly discriminate classical pancreatic lipases (poorly inhibited) from gastric lipase (fully inhibited). Among them, the 5-(2-(Benzyloxy)ethoxy)-3-(3-PhenoxyPhenyl)-1,3,4-Oxadiazol-2(3H)-one (BemPPOX) was identified as the most potent inhibitor of DGL, even more active than the FDA-approved drug Orlistat. BemPPOX and Orlistat were further compared in vitro in the course of test meal digestion, and in vivo with a mesenteric lymph duct cannulated rat model to evaluate their respective impacts on fat absorption. While Orlistat inhibited both gastric and duodenal lipolysis and drastically reduced fat absorption in rats, BemPPOX showed a specific action on gastric lipolysis that slowed down the overall lipolysis process and led to a subsequent reduction of around 55% of the intestinal absorption of fatty acids compared to controls. All these data promote BemPPOX as a potent candidate to efficiently regulate the gastrointestinal lipolysis, and to investigate its link with satiety mechanisms and therefore develop new strategies to "fight against obesity".
ESTHER : Point_2016_Eur.J.Med.Chem_123_834
PubMedSearch : Point_2016_Eur.J.Med.Chem_123_834
PubMedID: 27543878
Gene_locus related to this paper: canfa-1lipg , human-LIPF

Title : Effect of preduodenal lipase inhibition in suckling rats on dietary octanoic acid (C8:0) gastric absorption and plasma octanoylated ghrelin concentration - Lemarie_2016_Biochim.Biophys.Acta_1861_1111
Author(s) : Lemarie F , Cavalier JF , Garcia C , Boissel F , Point V , Catheline D , Legrand P , Carriere F , Rioux V
Ref : Biochimica & Biophysica Acta , 1861 :1111 , 2016
Abstract : Part of medium chain fatty acids (MCFAs) coming from dietary triglycerides (TGs) can be directly absorbed through the gastric mucosa after the action of preduodenal lipase (lingual lipase in the rat). MCFA gastric absorption, particularly that of octanoic acid (C8:0), may have a physiological importance in the octanoylation of ghrelin, the orexigenic gastric peptide acting as an endogenous ligand of the hypothalamic growth hormone secretagogue receptor 1a (GHSR-1a). However, the amount of C8:0 absorbed in the stomach and its metabolic fate still haven't been clearly characterized. The purpose of the present study was to further characterize and quantify the importance of preduodenal lipase activity on the release and gastric absorption of dietary C8:0 and on the subsequent ghrelin octanoylation in the stomach mucosa. Fifteen days old rats received fat emulsions containing triolein or [1,1,1-(13)C]-Tri-C8:0 and a specific inhibitor of preduodenal lipase, 5-(2-(benzyloxy)ethoxy)-3-(3-phenoxyphenyl)-1,3,4-oxadiazol-2(3H)-one or BemPPOX. The fate of the (13)C-C8:0 was followed in rat tissues after 30 and 120min of digestion and octanoylated ghrelin was measured in the plasma. This work (1) demonstrates that part of C8:0 coming from Tri-C8:0 is directly absorbed at the gastric level, (2) allows the estimation of C8:0 gastric absorption level (1.3% of the (13)C-C8:0 in sn-3 position after 30min of digestion), as well as (3) the contribution of rat lingual lipase to total lipolysis and to duodenal absorption of dietary FAs (at least 30%), (4) shows no short-term effect of dietary Tri-C8:0 consumption and subsequent increase of C8:0 gastric tissue content on plasma octanoylated ghrelin concentration.
ESTHER : Lemarie_2016_Biochim.Biophys.Acta_1861_1111
PubMedSearch : Lemarie_2016_Biochim.Biophys.Acta_1861_1111
PubMedID: 27317984

Title : Biochemical characterization of Yarrowia lipolytica LIP8, a secreted lipase with a cleavable C-terminal region - Kamoun_2015_Biochim.Biophys.Acta_1851_129
Author(s) : Kamoun J , Schue M , Messaoud W , Baignol J , Point V , Mateos-Diaz E , Mansuelle P , Gargouri Y , Parsiegla G , Cavalier JF , Carriere F , Aloulou A
Ref : Biochimica & Biophysica Acta , 1851 :129 , 2015
Abstract : Yarrowia lipolytica is a lipolytic yeast possessing 16 paralog genes coding for lipases. Little information on these lipases has been obtained and only the major secreted lipase, namely YLLIP2, had been biochemically and structurally characterized. Another secreted lipase, YLLIP8, was isolated from Y. lipolytica culture medium and compared with the recombinant enzyme produced in Pichia pastoris. N-terminal sequencing showed that YLLIP8 is produced in its active form after the cleavage of a signal peptide. Mass spectrometry analysis revealed that YLLIP8 recovered from culture medium lacks a C-terminal part of 33 amino acids which are present in the coding sequence. A 3D model of YLLIP8 built from the X-ray structure of the homologous YLLIP2 lipase shows that these truncated amino acids in YLLIP8 belong to an additional C-terminal region predicted to be mainly helical. Western blot analysis shows that YLLIP8 C-tail is rapidly cleaved upon enzyme secretion since both cell-bound and culture supernatant lipases lack this extension. Mature recombinant YLLIP8 displays a true lipase activity on short-, medium- and long-chain triacylglycerols (TAG), with an optimum activity at alkaline pH on medium chain TAG. It has no apparent regioselectivity in TAG hydrolysis, thus generating glycerol and FFAs as final lipolysis products. YLLIP8 properties are distinct from those of the 1,3-regioselective YLLIP2, acting optimally at acidic pH. These lipases are tailored for complementary roles in fatty acid uptake by Y. lipolytica.
ESTHER : Kamoun_2015_Biochim.Biophys.Acta_1851_129
PubMedSearch : Kamoun_2015_Biochim.Biophys.Acta_1851_129
PubMedID: 25449652
Gene_locus related to this paper: yarli-LIP8

Title : An interfacial and comparative in vitro study of gastrointestinal lipases and Yarrowia lipolytica LIP2 lipase, a candidate for enzyme replacement therapy - Benarouche_2014_Biochimie_102_145
Author(s) : Benarouche A , Point V , Carriere F , Cavalier JF
Ref : Biochimie , 102 :145 , 2014
Abstract : Lipolytic activities of Yarrowia lipolytica LIP2 lipase (YLLIP2), human pancreatic (HPL) and dog gastric (DGL) lipases were first compared using lecithin-stabilized triacylglycerol (TAG) emulsions (Intralipid) at various pH and bile salt concentrations. Like DGL, YLLIP2 was able to hydrolyze TAG droplets covered by a lecithin monolayer, while HPL was not directly active on that substrate. These results were in good agreement with the respective kinetics of adsorption on phosphatidylcholine (PC) monomolecular films of the same three lipases, YLLIP2 being the most tensioactive lipase. YLLIP2 adsorption onto a PC monolayer spread at the air/water interface was influenced by pH-dependent changes in the enzyme/lipid interfacial association constant (KAds) which was optimum at pH 6.0 on long-chain egg PC monolayer, and at pH 5.0 on medium chain dilauroylphosphatidylcholine film. Using substrate monolayers (1,2-dicaprin, trioctanoin), YLLIP2 displayed the highest lipolytic activities on both substrates in the 25-35 mN m(-1) surface pressure range. YLLIP2 was active in a large pH range and displayed a pH-dependent activity profile combining DGL and HPL features at pH values found in the stomach (pH 3-5) and in the intestine (pH 6-7), respectively. The apparent maximum activity of YLLIP2 was observed at acidic pH 4-6 and was therefore well correlated with an efficient interfacial binding at these pH levels, whatever the type of interfaces (Intralipid emulsions, substrate or PC monolayers). All these findings support the use of YLLIP2 in enzyme replacement therapy for the treatment of pancreatic exocrine insufficiency, a pathological situation in which an acidification of intestinal contents occurs.
ESTHER : Benarouche_2014_Biochimie_102_145
PubMedSearch : Benarouche_2014_Biochimie_102_145
PubMedID: 24650780

Title : Using the reversible inhibition of gastric lipase by Orlistat for investigating simultaneously lipase adsorption and substrate hydrolysis at the lipid-water interface - Benarouche_2014_Biochimie_101_221
Author(s) : Benarouche A , Point V , Carriere F , Cavalier JF
Ref : Biochimie , 101 :221 , 2014
Abstract : The lipolysis reaction carried out by lipases at the water-lipid interface is a complex process including enzyme conformational changes, adsorption/desorption equilibrium and substrate hydrolysis. Mixed monomolecular films of the lipase inhibitor Orlistat and 1,2-dicaprin were used here to investigate the adsorption of dog gastric lipase (DGL) followed by the hydrolysis of 1,2-dicaprin. The combined study of these two essential catalysis steps was made possible thanks to the highest affinity of DGL for Orlistat than 1,2-dicaprin and the fact that the inhibition of DGL by Orlistat is reversible. Upon DGL binding to mixed 1,2-dicaprin/Orlistat monolayers, an increase in surface pressure reflecting lipase adsorption was first recorded. Limited amounts of Orlistat allowed to maintain DGL inactive on 1,2-dicaprin during a period of time that was sufficient to determine DGL adsorption and desorption rate constants. A decrease in surface pressure reflecting 1,2-dicaprin hydrolysis and product desorption was observed after the slow hydrolysis of the covalent DGL-Orlistat complex was complete. The rate of 1,2-dicaprin hydrolysis was recorded using the surface barostat technique. Based on a kinetic model describing the inhibition by Orlistat and the activity of DGL on a mixed 1,2-dicaprin/Orlistat monolayer spread at the air-water interface combined with surface pressure measurements, it was possible to monitor DGL adsorption at the lipid-water interface and substrate hydrolysis in the course of a single experiment. This allowed to assess the kcat/KM* ratio for DGL acting on 1,2-dicaprin monolayer, after showing that mixed monolayers containing a low fraction of Orlistat were similar to pure 1,2-dicaprin monolayers.
ESTHER : Benarouche_2014_Biochimie_101_221
PubMedSearch : Benarouche_2014_Biochimie_101_221
PubMedID: 24508576

Title : Enantioselective inhibition of microbial lipolytic enzymes by nonracemic monocyclic enolphosphonate analogues of cyclophostin - Point_2013_J.Med.Chem_56_4393
Author(s) : Point V , Malla RK , Carriere F , Canaan S , Spilling CD , Cavalier JF
Ref : Journal of Medicinal Chemistry , 56 :4393 , 2013
Abstract : Four nonracemic enolphosphonate analogues of Cyclophostin were obtained by asymmetric synthesis, and their absolute configurations at both phosphorus and C-5 carbon chiral centers were unambiguously assigned. The influence of chirality was studied by testing the inhibitory effects of these four stereoisomers toward the lipolytic activity of three microbial lipases: Fusarium solani cutinase, Rv0183, and LipY from Mycobacterium tuberculosis . Cutinase was highly diastereoselective for the (Sp) configuration using (Sc) inhibitors, whereas no obvious stereopreference at phosphorus was observed with (Rc) compounds. Conversely, Rv0183 exhibited strong enantioselective discrimination for (Sp) configuration regardless of the chirality at the asymmetric carbon atom. Lastly, LipY discriminated only the unusual diastereoisomeric configuration (Rc, Rp) leading to the most potent inhibitor. This work, which provides a fundamental premise for the understanding of the stereoselective relationships between nonracemic enolphosphonates and their inhibitory activity, also opens new prospects on the design and synthesis of highly specific enantioselective antimicrobial agents.
ESTHER : Point_2013_J.Med.Chem_56_4393
PubMedSearch : Point_2013_J.Med.Chem_56_4393
PubMedID: 23651298

Title : Effects of the propeptide of group X secreted phospholipase A(2) on substrate specificity and interfacial activity on phospholipid monolayers - Point_2013_Biochimie_95_51
Author(s) : Point V , Benarouche A , Jemel I , Parsiegla G , Lambeau G , Carriere F , Cavalier JF
Ref : Biochimie , 95 :51 , 2013
Abstract : Group X secreted phospholipase A(2) (GX sPLA(2)) plays important physiological roles in the gastrointestinal tract, in immune and sperm cells and is involved in several types of inflammatory diseases. It is secreted either as a mature enzyme or as a mixture of proenzyme (with a basic 11 amino acid propeptide) and mature enzyme. The role of the propeptide in the repression of sPLA(2) activity has been studied extensively using liposomes and micelles as model interfaces. These substrates are however not always suitable for detecting some fine tuning of lipolytic enzymes. In the present study, the monolayer technique is used to compare PLA(2) activity of recombinant mouse GX sPLA(2) (mGX) and its pro-form (PromGX) on monomolecular films of dilauroyl-phosphatidyl-ethanolamine (DLPE), -choline (DLPC) and -glycerol (DLPG). The PLA(2) activity and substrate specificity of mGX (PE approximately PG > PC) were found to be surface pressure-dependent. mGX displayed a high activity on DLPE and DLPG but not on DLPC monolayers up to surface pressures corresponding to the lateral pressure of biological membranes (30-35 mN/m). Overall, the propeptide impaired the enzyme activity, particularly on DLPE whatever the surface pressure. However some conditions could be found where the propeptide had little effects on the repression of PLA(2) activity. In particular, both PromGX and mGX had similar activities on DLPG at a surface pressure of 30 mN/m. These findings show that PromGX can be potentially active depending on the presentation of the substrate (i.e., lipid packing) and one cannot exclude such an activity in a physiological context. A structural model of PromGX was built to investigate how the propeptide controls the activity of GX sPLA(2). This model shows that the propeptide is located within the interfacial binding site (i-face) and could disrupt both the interfacial binding of the enzyme and the access to the active site by steric hindrance.
ESTHER : Point_2013_Biochimie_95_51
PubMedSearch : Point_2013_Biochimie_95_51
PubMedID: 22967966

Title : New insights into the pH-dependent interfacial adsorption of dog gastric lipase using the monolayer technique - Benarouche_2013_Colloids.Surf.B.Biointerfaces_111_306
Author(s) : Benarouche A , Point V , Parsiegla G , Carriere F , Cavalier JF
Ref : Colloids Surf B Biointerfaces , 111 :306 , 2013
Abstract : The access to kinetic parameters of lipolytic enzyme adsorption onto lipids is essential for a better understanding of interfacial enzymology and lipase-lipid interactions. The interfacial adsorption of dog gastric lipase (DGL) was monitored as a function of pH and surface pressure (Pi), independently from the catalytic activity, using non-hydrolysable 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) monomolecular films. The acid-stable DGL, which initiates fat digestion in the stomach, was then selected because its adsorption kinetics onto hydrophobic solid surfaces were already studied. This gastric lipase was therefore used as a model enzyme to validate both experimental and theoretical approaches. Results show that the adsorption process of DGL at the lipid/water interface depends on a pH-dependent adsorption equilibrium coefficient which is optimum at pH 5.0 (K(Ads) = 1.7 +/- 0.05 x 10(8)M(-1)). KAds values further allowed an indirect estimation of the molar fraction (PhiE*(%), mol%) as well as the molecular area (AE*) of DGL adsorbed onto DLPC monolayer. Based on these data, a model for DGL adsorption onto DLPC monolayer at pH 5.0 is proposed for a surface pressure range of 15-25 mNm(-1).
ESTHER : Benarouche_2013_Colloids.Surf.B.Biointerfaces_111_306
PubMedSearch : Benarouche_2013_Colloids.Surf.B.Biointerfaces_111_306
PubMedID: 23838197

Title : The galactolipase activity of some microbial lipases and pancreatic enzymes - Amara_2013_Eur.J.Lipid.Sci.Technol_115_442
Author(s) : Amara S , Lafont D , Parsiegla G , Point V , Chabannes A , Rousset A , Carriere F
Ref : Eur J Lipid Sci Technol , 115 :442 , 2013
Abstract : Several well known microbial lipases were screened for their ability to hydrolyze synthetic medium chain monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG). Fusarium solani cutinase and Thermomyces lanuginosus lipase (TLL) were found to hydrolyze MGDG at high rates (984 +/- 62 and 450 +/-41 U/mg, respectively). These activities remained however lower than those measured with pancreatic lipase-related protein 2 (PLRP2) on the same substrate. As previously observed with PLRP2, galactolipid-bile salt mixed micelles were found to be the best substrate form for microbial enzymes. The galactolipid to bile salt molar ratios for measuring maximum galactolipase activities were found to be similar to those previously established with PLRP2, suggesting that bile salts have mainly an effect on the substrate and not on the enzyme itself. The galactolipase activity of cutinase and TLL, as well as human and guinea pig PLRP2s were also measured using galactolipid monomolecular films. Enzymes having a lid (TLL and human PLRP2) were found to act at higher surface pressures than those with no lid (cutinase and guinea pig PLRP2). In silico docking of medium chain MGDG and DGDG in the active site of guinea pig PLRP2 and TLL reveals some structural analogies between these enzymes
ESTHER : Amara_2013_Eur.J.Lipid.Sci.Technol_115_442
PubMedSearch : Amara_2013_Eur.J.Lipid.Sci.Technol_115_442
Gene_locus related to this paper: bovin-balip , human-CEL

Title : Synthesis and kinetic evaluation of cyclophostin and cyclipostins phosphonate analogs as selective and potent inhibitors of microbial lipases - Point_2012_J.Med.Chem_55_10204
Author(s) : Point V , Malla RK , Diomande S , Martin BP , Delorme V , Carriere F , Canaan S , Rath NP , Spilling CD , Cavalier JF
Ref : Journal of Medicinal Chemistry , 55 :10204 , 2012
Abstract : A new series of customizable diastereomeric cis- and trans-monocyclic enol-phosphonate analogs to Cyclophostin and Cyclipostins were synthesized. Their potencies and mechanisms of inhibition toward six representative lipolytic enzymes belonging to distinct lipase families were examined. With mammalian gastric and pancreatic lipases no inhibition occurred with any of the compounds tested. Conversely, Fusarium solani Cutinase and lipases from Mycobacterium tuberculosis (Rv0183 and LipY) were all fully inactivated. The best inhibitors displayed a cis conformation (H and OMe) and exhibited higher inhibitory activities than the lipase inhibitor Orlistat toward the same enzymes. Our results have revealed that chemical group at the gamma-carbon of the phosphonate ring strongly impacts the inhibitory efficiency, leading to a significant improvement in selectivity toward a target lipase over another. The powerful and selective inhibition of microbial (fungal and mycobacterial) lipases suggests that these seven-membered monocyclic enol-phosphonates should provide useful leads for the development of novel and highly selective antimicrobial agents.
ESTHER : Point_2012_J.Med.Chem_55_10204
PubMedSearch : Point_2012_J.Med.Chem_55_10204
PubMedID: 23095026

Title : Analysis of the discriminative inhibition of mammalian digestive lipases by 3-phenyl substituted 1,3,4-oxadiazol-2(3H)-ones. - Point_2012_Eur.J.Med.Chem_58_452
Author(s) : Point V , Pavan Kumar KV , Marc S , Delorme V , Parsiegla G , Amara S , Carriere F , Buono G , Fotiadu F , Canaan S , Leclaire J , Cavalier JF
Ref : Eur Journal of Medicinal Chemistry , 58 :452 , 2012
Abstract : We report here the reactivity and selectivity of three 5-Methoxy-N-3-Phenyl substituted-1,3,4-Oxadiazol-2(3H)-ones (MPOX, as well as meta and para-PhenoxyPhenyl derivatives, i.e.MmPPOX and MpPPOX) with respect to the inhibition of mammalian digestive lipases: dog gastric lipase (DGL), human (HPL) and porcine (PPL) pancreatic lipases, human (HPLRP2) and guinea pig (GPLRP2) pancreatic lipase-related proteins 2, human pancreatic carboxyl ester hydrolase (hCEH), and porcine pancreatic extracts (PPE). All three oxadiazolones displayed similar inhibitory activities on DGL, PLRP2s and hCEH than the FDA-approved anti-obesity drug Orlistat towards the same enzymes. These compounds appeared however to be discriminative of HPL (poorly inhibited) and PPL (fully inhibited). The inhibitory activities obtained experimentally in vitro were further rationalized using in silico molecular docking. In the case of DGL, we demonstrated that the phenoxy group plays a key role in specific molecular interactions within the lipase's active site. The absence of this group in the case of MPOX, as well as its connectivity to the neighbouring aromatic ring in the case of MmPPOX and MpPPOX, strongly impacts the inhibitory efficiency of these oxadiazolones and leads to a significant gain in selectivity towards the lipases tested. The powerful inhibition of PPL, DGL, PLRP2s, hCEH and to a lesser extend HPL, suggests that oxadiazolone derivatives could also provide useful leads for the development of novel and more discriminative inhibitors of digestive lipases. These inhibitors could be used for a better understanding of individual lipase function as well as for drug development aiming at the regulation of the whole gastrointestinal lipolysis process.
ESTHER : Point_2012_Eur.J.Med.Chem_58_452
PubMedSearch : Point_2012_Eur.J.Med.Chem_58_452
PubMedID: 23153815
Gene_locus related to this paper: canfa-1lipg , cavpo-2plrp , human-CEL , human-PNLIP , human-PNLIPRP2 , pig-1plip