1
|
Lim JW, Shin KS, Ryu YS, Lee Y, Lee SK, Kim T. High-Throughput Screening of Acyl-CoA Thioesterase I Mutants Using a Fluid Array Platform. ACS OMEGA 2019; 4:21848-21854. [PMID: 31891062 PMCID: PMC6933594 DOI: 10.1021/acsomega.9b02826] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
Screening target microorganisms from a mutated recombinant library plays a crucial role in advancing synthetic biology and metabolic engineering. However, conventional screening tools have several limitations regarding throughput, cost, and labor. Here, we used the fluid array platform to conduct high-throughput screening (HTS) that identified Escherichia coli 'TesA thioesterase mutants producing elevated yields of free fatty acids (FFAs) from a large (106) mutant library. A growth-based screening method using a TetA-RFP fusion sensing mechanism and a reporter-based screening method using high-level FFA producing mutants were employed to identify these mutants via HTS. The platform was able to cover >95% of the mutation library, and it screened target cells from many arrays of the fluid array platform so that a post-analysis could be conducted by gas chromatography. The 'TesA mutation of each isolated mutant showing improved FFA production in E. coli was characterized, and its enhanced FFA production capability was confirmed.
Collapse
Affiliation(s)
- Ji Won Lim
- Department
of Biomedical Engineering, Department of Mechanical Engineering, and Department of
Chemical Engineering, Ulsan National Institute
of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulsan 44919, Republic
of Korea
| | - Kwang Soo Shin
- Department
of Biomedical Engineering, Department of Mechanical Engineering, and Department of
Chemical Engineering, Ulsan National Institute
of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulsan 44919, Republic
of Korea
| | - Young Shin Ryu
- Department
of Biomedical Engineering, Department of Mechanical Engineering, and Department of
Chemical Engineering, Ulsan National Institute
of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulsan 44919, Republic
of Korea
| | - Yongjoo Lee
- Department
of Biomedical Engineering, Department of Mechanical Engineering, and Department of
Chemical Engineering, Ulsan National Institute
of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulsan 44919, Republic
of Korea
| | - Sung Kuk Lee
- Department
of Biomedical Engineering, Department of Mechanical Engineering, and Department of
Chemical Engineering, Ulsan National Institute
of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulsan 44919, Republic
of Korea
| | - Taesung Kim
- Department
of Biomedical Engineering, Department of Mechanical Engineering, and Department of
Chemical Engineering, Ulsan National Institute
of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulsan 44919, Republic
of Korea
| |
Collapse
|
2
|
Update on the molecular biology of dyslipidemias. Clin Chim Acta 2016; 454:143-85. [DOI: 10.1016/j.cca.2015.10.033] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/24/2015] [Accepted: 10/30/2015] [Indexed: 12/20/2022]
|
3
|
Sensi C, Simonelli S, Zanotti I, Tedeschi G, Lusardi G, Franceschini G, Calabresi L, Eberini I. Distant homology modeling of LCAT and its validation through in silico targeting and in vitro and in vivo assays. PLoS One 2014; 9:e95044. [PMID: 24736652 PMCID: PMC3988154 DOI: 10.1371/journal.pone.0095044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 03/23/2014] [Indexed: 11/18/2022] Open
Abstract
LCAT (lecithin:cholesterol acyltransferase) catalyzes the transacylation of a fatty acid of lecithin to cholesterol, generating a cholesteryl ester and lysolecithin. The knowledge of LCAT atomic structure and the identification of the amino acids relevant in controlling its structure and function are expected to be very helpful to understand the enzyme catalytic mechanism, as involved in HDL cholesterol metabolism. However - after an early report in the late ‘90 s - no recent advance has been made about LCAT three-dimensional structure. In this paper, we propose an LCAT atomistic model, built following the most up-to-date molecular modeling approaches, and exploiting newly solved crystallographic structures. LCAT shows the typical folding of the α/β hydrolase superfamily, and its topology is characterized by a combination of α-helices covering a central 7-strand β-sheet. LCAT presents a Ser/Asp/His catalytic triad with a peculiar geometry, which is shared with such other enzyme classes as lipases, proteases and esterases. Our proposed model was validated through different approaches. We evaluated the impact on LCAT structure of some point mutations close to the enzyme active site (Lys218Asn, Thr274Ala, Thr274Ile) and explained, at a molecular level, their phenotypic effects. Furthermore, we devised some LCAT modulators either designed through a de novo strategy or identified through a virtual high-throughput screening pipeline. The tested compounds were proven to be potent inhibitors of the enzyme activity.
Collapse
Affiliation(s)
- Cristina Sensi
- Laboratorio di Biochimica e Biofisica Computazionale, Università degli Studi di Milano, Milano, Italia
| | - Sara Simonelli
- Centro Enrica Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italia
| | - Ilaria Zanotti
- Dipartimento di Farmacia, Università Degli Studi di Parma, Parma, Italia
| | - Gabriella Tedeschi
- Dipartimento di Scienze Veterinarie e Sanità Pubblica, Università degli Studi di Milano, Milano, Italia
| | - Giulia Lusardi
- Dipartimento di Farmacia, Università Degli Studi di Parma, Parma, Italia
| | - Guido Franceschini
- Centro Enrica Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italia
| | - Laura Calabresi
- Centro Enrica Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italia
| | - Ivano Eberini
- Laboratorio di Biochimica e Biofisica Computazionale, Università degli Studi di Milano, Milano, Italia
- * E-mail:
| |
Collapse
|
4
|
Amar MJA, Shamburek RD, Vaisman B, Knapper CL, Foger B, Hoyt RF, Santamarina-Fojo S, Brewer HB, Remaley AT. Adenoviral expression of human lecithin-cholesterol acyltransferase in nonhuman primates leads to an antiatherogenic lipoprotein phenotype by increasing high-density lipoprotein and lowering low-density lipoprotein. Metabolism 2009; 58:568-75. [PMID: 19303980 PMCID: PMC3703629 DOI: 10.1016/j.metabol.2008.11.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Accepted: 11/26/2008] [Indexed: 01/30/2023]
Abstract
Lecithin-cholesterol acyltransferase (LCAT), a key enzyme in high-density lipoprotein (HDL) metabolism, has been proposed to have atheroprotective properties by promoting reverse cholesterol transport. Overexpression of LCAT in various animal models, however, has led to conflicting results on its overall effect on lipoproteins and atherosclerosis. In this study, the effect of overexpression of LCAT in nonhuman primates on lipoprotein metabolism is examined. Human LCAT was expressed with adenovirus in squirrel monkeys (n = 8), resulting on day 4 in a 22-fold increase of LCAT activity (257 +/- 23 vs 5618 +/- 799 nmol mL(-1) h(-1), P < .0001). At its peak, LCAT was found to nearly double the level of HDL cholesterol from baseline (113 +/- 7 vs 260 +/- 24 mg/dL, P < .01). High-density lipoprotein formed after treatment with the adenovirus was larger in size, as assessed by fast protein liquid chromatography (FPLC) analysis. By kinetic studies, it was determined that there was a decrease in apolipoprotein (Apo) A-I resident time (0.373 +/- 0.027 vs 0.685 +/- 0.045 d(-1), P < .0001) and almost a doubling in the ApoA-I synthetic rate (22 +/- 2 vs 41 +/- 3 mg kg(-1) d(-1), P < .0001), but no overall change in ApoA-I levels. In addition, increased expression of LCAT was associated with a 37% reduction of ApoB levels (12 +/- 1 vs 19 +/- 1 mg/dL, P < .05) due to increased low-density lipoprotein catabolism (fractional catabolic rate = 1.7 +/- 0.1 d(-1) in controls vs 4.2 +/- 0.3 d(-1) in LCAT-treated group, P < .05). In summary, overexpression of LCAT in nonhuman primates leads to an antiatherogenic lipoprotein profile by increasing HDL cholesterol and lowering ApoB, thus making LCAT a potential drug target for reducing atherosclerosis.
Collapse
Affiliation(s)
- Marcelo J A Amar
- Lipoprotein Metabolism Section, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Sorci-Thomas MG, Bhat S, Thomas MJ. Activation of lecithin:cholesterol acyltransferase by HDL ApoA-I central helices. CLINICAL LIPIDOLOGY 2009; 4:113-124. [PMID: 20582235 PMCID: PMC2891274 DOI: 10.2217/17584299.4.1.113] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Lecithin:cholesterol acyltransferase (LCAT) is an enzyme that first hydrolyzes the sn-2 position of phospholipids, preferentially a diacylphosphocholine, and then transfers the fatty acid to cholesterol to yield a cholesteryl ester. HDL ApoA-I is the principal catalytic activator for LCAT. Activity of LCAT on nascent or lipid-poor HDL particles composed of phospholipid, cholesterol and ApoA-I allows the maturation of HDL particles into lipid-rich spherical particles that contain a core of cholesteryl ester surrounded by phospholipid and ApoA-I on the surface. This article reviews the recent progress in elucidating structural aspects of the interaction between LCAT and ApoA-I. In the last decade, there has been considerable progress in understanding the structure of ApoA-I and the central helices 5, 6, and 7 that are known to activate LCAT. However, much less information has been forthcoming describing the 3D structure and conformation of LCAT required to catalyze two separate reactions within a single monomeric peptide.
Collapse
Affiliation(s)
- Mary G Sorci-Thomas
- Department of Pathology, Wake Forest University School of Medicine, Medical Center Blvd, Winston-Salem, NC 27157-1016, USA, Tel.: +1 336 716 2147, Fax: +1 336 716 6279,
| | - Shaila Bhat
- Department of Pathology, Lipid Sciences Research Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA, Tel.: +1 336 716 6062, Fax: +1 336 716 6279,
| | - Michael J Thomas
- Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA, Tel.: +1 336 716 2313, Fax: +1 336 716 6279,
| |
Collapse
|
6
|
Reshetnyak Y, Tchedre KT, Nair MP, Pritchard PH, Lacko AG. Structural differences between wild-type and fish eye disease mutant of lecithin:cholesterol acyltransferase. J Biomol Struct Dyn 2006; 24:75-82. [PMID: 16780378 DOI: 10.1080/07391102.2006.10507101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Fluorescence spectroscopy has been used to investigate the conformational changes that occur upon binding of wild type (WT) and mutant (Thr123Ile) lecithin:cholesterol acyltransferase (LCAT) to the potential substrates (dioleoyl-phosphatidyl choline [DOPC] and high density lipoprotein [HDL]). For a detailed analysis of structural differences between WT and mutant LCAT, we performed decompositional analysis of a set of tryptophan fluorescence spectra, measured at increasing concentrations of external quenchers (acrylamide and KI). The data obtained show that Thr123Ile mutation in LCAT leads to a conformation that is likely to be more rigid (less mobile/flexible) than that of the WT protein with a redistribution of charged residues around exposed tryptophan fluorophores. We propose that the redistribution of charged residues in mutant LCAT may be a major factor responsible for the dramatically reduced activity of the enzyme with HDL and reconstituted high density lipoprotein (rHDL).
Collapse
Affiliation(s)
- Yana Reshetnyak
- Department of Physics, University of Rhode Island, Kingston, Rhode Island 02881, USA.
| | | | | | | | | |
Collapse
|
7
|
Calabresi L, Moleri E, Franceschini G. LCAT deficiency: molecular genetics, lipid/lipoprotein phenotype and atherosclerosis. ACTA ACUST UNITED AC 2006. [DOI: 10.2217/17460875.1.3.241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
8
|
Pisciotta L, Calabresi L, Lupattelli G, Siepi D, Mannarino MR, Moleri E, Bellocchio A, Cantafora A, Tarugi P, Calandra S, Bertolini S. Combined monogenic hypercholesterolemia and hypoalphalipoproteinemia caused by mutations in LDL-R and LCAT genes. Atherosclerosis 2005; 182:153-9. [PMID: 16115486 DOI: 10.1016/j.atherosclerosis.2005.01.048] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2004] [Revised: 01/20/2005] [Accepted: 01/31/2005] [Indexed: 10/25/2022]
Abstract
We studied a three generation family with co-dominant monogenic hypercholesterolemia and hypoalphalipoproteinemia. The proband, a 48 year-old male, was found to be heterozygous for a previously reported mutation in LDL receptor (LDL-R) gene (IVS15-3 c>a) and a novel mutation in exon 6 of lecithin cholesterol acyltransferase (LCAT) gene (c.803 G>A) causing a non-synonymous amino acid substitution (p.R244H). These mutations segregated independently in the family. The LDL-R mutation was associated with high levels of LDL-C (6.20-9.85 mmol/L) and apo B (170-255 mg/dL), comparable to those previously reported in carriers of the same mutation. The LCAT mutation was associated with low levels of HDL-C (0.67-0.80 mmol/L) and apo A-I (96-110 mg/dL). The proband had reduced LCAT function, as measured by cholesterol esterification rate (29 nmol/(mL/h) versus 30-60 nmol/(mL/h)), LCAT activity (10 nmol/(mL/h) versus 20-55 nmol/(mL/h)) and LCAT mass (2.87 microg/mL versus 3.1-6.7 microg/mL). Carriers of LCAT mutation had lower LCAT activity and a tendency to reduced cholesterol esterification rate (CER) and LCAT mass as compared to non-carrier family members. The LCAT mutation was not found in 80 control subjects and 60 patients with primary hypoalphalipoproteinemia. Despite the unfavourable lipoprotein profile, the proband had only mild clinical signs of atherosclerosis. This unexpected finding is probably due to the intensive lipid lowering treatment the patient has been on over the last decade.
Collapse
Affiliation(s)
- Livia Pisciotta
- Department of Internal Medicine, University of Genoa, Viale Benedetto XV 6, I-16132 Genoa, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Calabresi L, Pisciotta L, Costantin A, Frigerio I, Eberini I, Alessandrini P, Arca M, Bon GB, Boscutti G, Busnach G, Frascà G, Gesualdo L, Gigante M, Lupattelli G, Montali A, Pizzolitto S, Rabbone I, Rolleri M, Ruotolo G, Sampietro T, Sessa A, Vaudo G, Cantafora A, Veglia F, Calandra S, Bertolini S, Franceschini G. The Molecular Basis of Lecithin:Cholesterol Acyltransferase Deficiency Syndromes. Arterioscler Thromb Vasc Biol 2005; 25:1972-8. [PMID: 15994445 DOI: 10.1161/01.atv.0000175751.30616.13] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
To better understand the role of lecithin:cholesterol acyltransferase (LCAT) in lipoprotein metabolism through the genetic and biochemical characterization of families carrying mutations in the
LCAT
gene.
Methods and Results—
Thirteen families carrying 17 different mutations in the
LCAT
gene were identified by Lipid Clinics and Departments of Nephrology throughout Italy. DNA analysis of 82 family members identified 15 carriers of 2 mutant
LCAT
alleles, 11 with familial LCAT deficiency (FLD) and 4 with fish-eye disease (FED). Forty-four individuals carried 1 mutant
LCAT
allele, and 23 had a normal genotype. Plasma unesterified cholesterol, unesterified/total cholesterol ratio, triglycerides, very-low-density lipoprotein cholesterol, and pre-β high-density lipoprotein (LDL) were elevated, and high-density lipoprotein (HDL) cholesterol, apolipoprotein A-I, apolipoprotein A-II, apolipoprotein B, LpA-I, LpA-I:A-II, cholesterol esterification rate, LCAT activity and concentration, and LDL and HDL
3
particle size were reduced in a gene–dose-dependent manner in carriers of mutant
LCAT
alleles. No differences were found in the lipid/lipoprotein profile of FLD and FED cases, except for higher plasma unesterified cholesterol and unesterified/total cholesterol ratio in the former.
Conclusion—
In a large series of subjects carrying mutations in the
LCAT
gene, the inheritance of a mutated LCAT genotype causes a gene–dose-dependent alteration in the plasma lipid/lipoprotein profile, which is remarkably similar between subjects classified as FLD or FED.
Collapse
Affiliation(s)
- Laura Calabresi
- Center E. Grossi Paoletti, Department of Pharmacological Sciences, University of Milano, 20133 Milan, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Miida T, Zhang B, Obayashi K, Seino U, Zhu Y, Ito T, Nakamura Y, Okada M, Saku K. T13M mutation of lecithin-cholesterol acyltransferase gene causes fish-eye disease. Clin Chim Acta 2004; 343:201-8. [PMID: 15115696 DOI: 10.1016/j.cccn.2004.01.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Revised: 01/19/2004] [Accepted: 01/21/2004] [Indexed: 11/28/2022]
Abstract
BACKGROUND Lecithin-cholesterol acyltransferase (LCAT) esterifies free cholesterol (FC) in plasma and plays a crucial role in the maturation of prebeta1-HDL (lipid-poor HDL) into alpha-migrating HDL (spherical HDL). Natural mutations of LCAT gene cause familial LCAT deficiency (FLD) or fish-eye disease (FED). The relationship between mutations and their phenotypes gives important clues to the functions of specific regions of LCAT. We investigated the first homozygous case with a substitution of threonine to methionine at codon 13 (T13M) of LCAT gene. METHODS We evaluated LCAT activity, LCAT distribution among HDL subfractions and conversion of prebeta1-HDL to alpha-migrating HDL by native two-dimensional gel electrophoresis (N-2DGE). RESULTS The proband had corneal opacity, severe hypo-alpha-lipoproteinemia, half-normal LCAT activity and near normal cholesteryl ester/total cholesterol (TC) ratio in plasma. These features were characteristic of FED. Plasma prebeta1-HDL concentration was near normal, but not converted to alpha-migrating HDL during 37 degrees C incubation. As expected, alpha-migrating HDL (especially large particles) was markedly reduced. In the immunoblot against LCAT, the small alpha-migrating HDL from the proband had much less LCAT in this patient than in controls. CONCLUSION T13M mutation of LCAT gene causes FED.
Collapse
Affiliation(s)
- Takashi Miida
- Division of Clinical Preventive Medicine, Department of Community Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, Asahimachi 1-757, Niigata, Niigata 951-8510, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|