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Lipid cholesterol metabolism mycobacterium tuberculosis

Melanie Genoula, José Luis Marín Franco, Maeva Dupont, Denise Kviatcovsky, Ayelén Milillo, Pablo Schierloh, Eduardo Jose Moraña, Susana Poggi, Domingo Palmero, Dulce Mata-Espinosa, Erika González-Domínguez, Juan Carlos León Contreras, Paula Barrionuevo, Bárbara Rearte, Marlina Olyissa Córdoba Moreno, Adriana Fontanals, Agostina Crotta Asis, Gabriela Gago, Céline Cougoule, Olivier Neyrolles, Isabelle Maridonneau-Parini, Carmen Sánchez-Torres, Rogelio Hernández-Pando, Christel Vérollet, Geanncarlo Lugo-Villarino, María Del Carmen Sasiain, Luciana Balboa
The ability of Mycobacterium tuberculosis (Mtb) to persist in its human host relies on numerous immune evasion strategies, such as the deregulation of the lipid metabolism leading to the formation of foamy macrophages (FM). Yet, the specific host factors leading to the foamy phenotype of Mtb-infected macrophages remain unknown. Herein, we aimed to address whether host cytokines contribute to FM formation in the context of Mtb infection. Our approach is based on the use of an acellular fraction of tuberculous pleural effusions (TB-PE) as a physiological source of local factors released during Mtb infection...
2018: Frontiers in Immunology
Glenn F W Walpole, Sergio Grinstein, Johannes Westman
Innate immunity relies on the effective recognition and elimination of pathogenic microorganisms. This entails sequestration of pathogens into phagosomes that promptly acquire microbicidal and degradative properties. This complex series of events, which involve cytoskeletal reorganization, membrane remodeling and the activation of multiple enzymes, is orchestrated by lipid signaling. To overcome this immune response, intracellular pathogens acquired mechanisms to subvert phosphoinositide-mediated signaling and use host lipids, notably cholesterol, as nutrients...
March 23, 2018: IUBMB Life
Piyali Basu, Noor Sanhu, Apoorva Bhatt, Albel Singh, Ricardo Balhana, Irene Gobe, Nicola A Crowhurst, Tom A Mendum, Liang Gao, Jane L Ward, Mike Beale, Johnjoe McFadden, Dany Jv Beste
Enzymes at the PEP-pyruvate-oxaloacetate or anaplerotic (ANA) node control the metabolic flux to glycolysis, gluconeogenesis and anaplerosis. Here we use genetic, biochemical and13 C isotopomer analysis to characterize the role of the enzymes at the ANA node during the intracellular survival of the world's most successful bacterial pathogen, Mycobacterium tuberculosis ( Mtb ). We show that each of the four ANA enzymes, pyruvate carboxylase (PCA), PEP carboxykinase (PCK), malic enzyme (MEZ), and pyruvate phosphate dikinase (PPDK), performs a unique and essential metabolic function during the intracellular survival of Mtb   We show that in addition to PCK, intracellular Mtb requires PPDK as an alternative gateway into gluconeogenesis...
February 23, 2018: Journal of Biological Chemistry
Diana A Aguilar-Ayala, Laurentijn Tilleman, Filip Van Nieuwerburgh, Dieter Deforce, Juan Carlos Palomino, Peter Vandamme, Jorge A Gonzalez-Y-Merchand, Anandi Martin
Tuberculosis (TB) is currently the number one killer among infectious diseases worldwide. Lipids are abundant molecules during the infectious cycle of Mycobacterium tuberculosis (Mtb) and studies better mimicking its actual metabolic state during pathogenesis are needed. Though most studies have focused on the mycobacterial lipid metabolism under standard culture conditions, little is known about the transcriptome of Mtb in a lipid environment. Here we determined the transcriptome of Mtb H37Rv in a lipid-rich environment (cholesterol and fatty acid) under aerobic and hypoxic conditions, using RNAseq...
December 15, 2017: Scientific Reports
Suman Asalla, Krishnaveni Mohareer, Sharmistha Banerjee
Mycobacterium tuberculosis ( M.tb) infection manifests into tuberculosis (TB) in a small fraction of the infected population that comprises the TB susceptible group. Identifying the factors potentiating susceptibility to TB persistence is one of the prime agenda of TB control programs. Recently, WHO recognized diabetes as a risk factor for TB disease progression. The closely related pathological state of metabolic imbalance, dyslipidemia, is yet another emerging risk factor involving deregulation in host immune responses...
2017: Frontiers in Cellular and Infection Microbiology
Pooja Singh, Rajesh Sinha, Gaurav Tyagi, Naresh Kumar Sharma, Neeraj K Saini, Amita Chandolia, Ashok Kumar Prasad, Mandira Varma-Basil, Mridula Bose
Lipid metabolism forms the heart and soul of Mycobacterium tuberculosis life cycle. Starting from macrophage invasion at cholesterol rich micro-domains to a sustainable survival for infection by utilizing cholesterol, Mycobacterium displays the nexus of metabolic pathways around host derived lipids. mce4 operon acts as cholesterol import system in M. tuberculosis and here we demonstrate role of mce4A gene of this operon in cholesterol catabolism. Here M. tuberculosis H37Rv overexpressing Rv3499c (mce4A) recombinant was used as a model to decipher the metabolic flux during intake and utilization of host lipids by mycobacteria...
February 5, 2018: Gene
Areej Abuhammad
Tuberculosis (TB), although a curable disease, is still one of the most difficult infections to treat. Mycobacterium tuberculosis infects 10 million people worldwide and kills 1.5 million people each year. Reactivation of a latent infection is the major cause of TB. Cholesterol is a critical carbon source during latent infection. Catabolism of cholesterol contributes to the pool of propionyl-CoA, a precursor that is incorporated into lipid virulence factors. The M. tuberculosis genome contains a large regulon of cholesterol catabolic genes suggesting that the microorganism can utilize host sterol for infection and persistence...
July 2017: British Journal of Pharmacology
Yaroslav Faletrov, Anna Brzostek, Renata Plocinska, Jarosław Dziadek, Elena Rudaya, Irina Edimecheva, Vladimir Shkumatov
Fluorescent steroids BODIPY-cholesterol (BPCh) and 7-nitrobenzoxadiazole-4-amino-(NBD)-labeled 22-NBD-chelesterol (22NC) as well as synthesized 20-(NBD)-pregn-5-en-3β-ol (20NP) were found to undergo bioconversions by Mycobacterium tuberculosis H37 Rv and M. smegmatis mc2 155. The major fluorescent products were determined to be 4-en-3-one derivatives of the compounds. Degradation of NBD fluorophore was also detected in the cases of 22NC and 20NP, but neither NBD degradation nor steroidal part modification were observed for the synthesized 3-(NBD)-cholestane...
January 2017: Steroids
Saikou Y Bah, Paul Dickinson, Thorsten Forster, Beate Kampmann, Peter Ghazal
Infection remains an important cause of morbidity and mortality. Natural defenses to infection are mediated by intrinsic/innate and adaptive immune responses. While our understanding is considerable it is incomplete and emerging areas of research such as those related to the immune-metabolic axis are only beginning to be appreciated. There is increasing evidence showing a connection between immune signalling and the regulation of sterol and fatty acid metabolism. In particular, metabolic intermediates of cholesterol biosynthesis and its oxidized metabolites (oxysterols) have been shown to regulate adaptive immunity and inflammation and for innate immune signalling to regulate the dynamics of cholesterol synthesis and homeostasis...
May 2017: Journal of Steroid Biochemistry and Molecular Biology
Rustin R Lovewell, Christopher M Sassetti, Brian C VanderVen
The interplay between Mycobacterium tuberculosis lipid metabolism, the immune response and lipid homeostasis in the host creates a complex and dynamic pathogen-host interaction. Advances in imaging and metabolic analysis techniques indicate that M. tuberculosis preferentially associates with foamy cells and employs multiple physiological systems to utilize exogenously derived fatty-acids and cholesterol. Moreover, novel insights into specific host pathways that control lipid accumulation during infection, such as the PPARγ and LXR transcriptional regulators, have begun to reveal mechanisms by which host immunity alters the bacterial micro-environment...
February 2016: Current Opinion in Microbiology
Maria Angela M Marques, Marcia Berrêdo-Pinho, Thabatta L S A Rosa, Venugopal Pujari, Robertha M R Lemes, Leticia M S Lery, Carlos Adriano M Silva, Ana Carolina R Guimarães, Georgia C Atella, William H Wheat, Patrick J Brennan, Dean C Crick, John T Belisle, Maria Cristina V Pessolani
UNLABELLED: Mycobacterium leprae induces the formation of lipid droplets, which are recruited to pathogen-containing phagosomes in infected macrophages and Schwann cells. Cholesterol is among the lipids with increased abundance in M. leprae-infected cells, and intracellular survival relies on cholesterol accumulation. The present study investigated the capacity of M. leprae to acquire and metabolize cholesterol. In silico analyses showed that oxidation of cholesterol to cholest-4-en-3-one (cholestenone), the first step of cholesterol degradation catalyzed by the enzyme 3β-hydroxysteroid dehydrogenase (3β-HSD), is apparently the only portion of the cholesterol catabolic pathway seen in Mycobacterium tuberculosis preserved by M...
December 2015: Journal of Bacteriology
Tom A Mendum, Huihai Wu, Andrzej M Kierzek, Graham R Stewart
BACKGROUND: Mycobacterium tuberculosis continues to kill more people than any other bacterium. Although its archetypal host cell is the macrophage, it also enters, and survives within, dendritic cells (DCs). By modulating the behaviour of the DC, M. tuberculosis is able to manipulate the host's immune response and establish an infection. To identify the M. tuberculosis genes required for survival within DCs we infected primary human DCs with an M. tuberculosis transposon library and identified mutations with a reduced ability to survive...
May 9, 2015: BMC Genomics
Jacob J Baker, Benjamin K Johnson, Robert B Abramovitch
During pathogenesis, Mycobacterium tuberculosis (Mtb) colonizes environments, such as the macrophage or necrotic granuloma, that are acidic and rich in cholesterol and fatty acids. The goal of this study was to examine how acidic pH and available carbon sources interact to regulate Mtb physiology. Here we report that Mtb growth at acidic pH requires host-associated carbon sources that function at the intersection of glycolysis and the TCA cycle, such as pyruvate, acetate, oxaloacetate and cholesterol. In contrast, in other tested carbon sources, Mtb fully arrests its growth at acidic pH and establishes a state of non-replicating persistence...
October 2014: Molecular Microbiology
Yun Lu, Feng Qiao, Xue-Fu You, Xin-Yi Yang
Identification and validation of a new target is one of the most important steps for new antituberculosis (TB) drug discovery. Researches have shown that Mycobacterium tuberculosis (Mtb) encodes 20 CYP450 enzymes which play important roles in the synthesis and metabolism of lipid, cholesterol utilization, and the electron transport of respiratory chain in Mtb. With the critical roles within the organism as well as the protein structures of six Mtb CYP450 enzymes being clarified, some of them have been highlighted as potential anti-tuberculosis targets...
April 2014: Yao Xue Xue Bao, Acta Pharmaceutica Sinica
Irène Caire-Brändli, Alexia Papadopoulos, Wladimir Malaga, David Marais, Stéphane Canaan, Lutz Thilo, Chantal de Chastellier
During the dormant phase of tuberculosis, Mycobacterium tuberculosis persists in lung granulomas by residing in foamy macrophages (FM) that contain abundant lipid bodies (LB) in their cytoplasm, allowing bacilli to accumulate lipids as intracytoplasmic lipid inclusions (ILI). An experimental model of FM is presented where bone marrow-derived mouse macrophages are infected with M. avium and exposed to very-low-density lipoprotein (VLDL) as a lipid source. Quantitative analysis of detailed electron microscope observations showed the following results...
February 2014: Infection and Immunity
Jin Gao, Nicole S Sampson
The Mycobacterium tuberculosis Rv3409c gene is required for modulation of the Toll-like receptor 2 (TLR-2) signaling response in infected macrophages. Although each is annotated as encoding a cholesterol oxidase, neither Rv3409c nor its ortholog MSMEG1604 is required for the metabolism of cholesterol in mycobacteria. Here we report that a unique lipid, L1334, accumulates in a MSMEG1604 transposon mutant in the Mycobacterium smegmatis cell envelope. L1334 is a polar glycopeptidolipid that is hyperrhamnosylated and in which the 6-deoxytalose moiety is not acetylated...
February 4, 2014: Biochemistry
Irène Caire-Brändli, Alexia Papadopoulos, Wladimir Malaga, David Marais, Stéphane Canaan, Lutz Thilo, Chantal de Chastellier
During the dormant phase of tuberculosis, Mycobacterium tuberculosis persists in lung granulomas by residing in foamy macrophages (FM) that contain abundant lipid bodies (LB) in their cytoplasm, allowing bacilli to accumulate lipids as intra-cytoplasmic lipid inclusions (ILI). An experimental model of FM is presented where bone marrow-derived mouse macrophages are infected with M. avium and exposed to very low density lipoprotein (VLDL) as a lipid source. Quantitative analysis of detailed electron microscope observations showed the following results: (i) Macrophages became foamy and mycobacteria formed ILI, for which host triacylglycerides, rather than cholesterol, was essential; (ii) Lipid transfer occurred via mycobacteria-induced fusion between LB and phagosomes; (iii) Mycobacteria showed a thinned cell wall and became elongated; (iv) Upon removal of VLDL, LB and ILI declined within hours and simultaneous resumption of mycobacterial division restored the number of mycobacteria to the same level as that found in untreated control macrophages...
November 25, 2013: Infection and Immunity
Wonsik Lee, Brian C VanderVen, Ruth J Fahey, David G Russell
Recent data indicate that the nutrients available to Mycobacterium tuberculosis (Mtb) inside its host cell are restricted in their diversity. Fatty acids and cholesterol appear more favored; however, their degradation can result in certain metabolic stresses. Their breakdown can generate propionyl-CoA, which gives rise to potentially toxic intermediates. Detoxification of propionyl-CoA relies on the activity of the methylcitrate cycle, the methylmalonyl pathway, or incorporation of the propionyl-CoA into methyl-branched lipids in the cell wall...
March 8, 2013: Journal of Biological Chemistry
Suzanne T Thomas, Brian C VanderVen, David R Sherman, David G Russell, Nicole S Sampson
Mycobacterium tuberculosis, the bacterium that causes tuberculosis, imports and metabolizes host cholesterol during infection. This ability is important in the chronic phase of infection. Here we investigate the role of the intracellular growth operon (igr), which has previously been identified as having a cholesterol-sensitive phenotype in vitro and which is important for intracellular growth of the mycobacteria. We have employed isotopically labeled low density lipoproteins containing either [1,7,15,22,26-(14)C]cholesterol or [1,7,15,22,26-(13)C]cholesterol and high resolution LC/MS as tools to profile the cholesterol-derived metabolome of an igr operon-disrupted mutant (Δigr) of M...
December 23, 2011: Journal of Biological Chemistry
Kevin W Bruhn, Chaitra Marathe, Ana Cláudia Maretti-Mira, Hong Nguyen, Jacquelyn Haskell, Thu Anh Tran, Veena Vanchinathan, Upasna Gaur, Mary E Wilson, Peter Tontonoz, Noah Craft
BACKGROUND: The liver X receptors (LXRs) are a family of nuclear receptor transcription factors that are activated by oxysterols and have defined roles in both lipid metabolism and cholesterol regulation. LXRs also affect antimicrobial responses and have anti-inflammatory effects in macrophages. As mice lacking LXRs are more susceptible to infection by intracellular bacteria Listeria monocytogenes and Mycobacterium tuberculosis, we hypothesized that LXR might also influence macrophage responses to the intracellular protozoan parasite Leishmania chagasi/infantum, a causative agent of visceral leishmaniasis...
November 16, 2010: PLoS Neglected Tropical Diseases
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