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Bär D, Konetschny B, Kulik A, Xu H, Paccagnella D, Beller P, Ziemert N, Dickschat JS, Gust B. Origin of the 3-methylglutaryl moiety in caprazamycin biosynthesis. Microb Cell Fact 2022; 21:232. [PMID: 36335365 PMCID: PMC9636800 DOI: 10.1186/s12934-022-01955-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022] Open
Abstract
Background Caprazamycins are liponucleoside antibiotics showing bioactivity against Gram-positive bacteria including clinically relevant Mycobacterium tuberculosis by targeting the bacterial MraY-translocase. Their chemical structure contains a unique 3-methylglutaryl moiety which they only share with the closely related liposidomycins. Although the biosynthesis of caprazamycin is understood to some extent, the origin of 3-methylglutaryl-CoA for caprazamycin biosynthesis remains elusive. Results In this work, we demonstrate two pathways of the heterologous producer Streptomyces coelicolor M1154 capable of supplying 3-methylglutaryl-CoA: One is encoded by the caprazamycin gene cluster itself including the 3-hydroxy-3-methylglutaryl-CoA synthase Cpz5. The second pathway is part of primary metabolism of the host cell and encodes for the leucine/isovalerate utilization pathway (Liu-pathway). We could identify the liu cluster in S. coelicolor M1154 and gene deletions showed that the intermediate 3-methylglutaconyl-CoA is used for 3-methylglutaryl-CoA biosynthesis. This is the first report of this intermediate being hijacked for secondary metabolite biosynthesis. Furthermore, Cpz20 and Cpz25 from the caprazamycin gene cluster were found to be part of a common route after both individual pathways are merged together. Conclusions The unique 3-methylglutaryl moiety in caprazamycin originates both from the caprazamycin gene cluster and the leucine/isovalerate utilization pathway of the heterologous host. Our study enhanced the knowledge on the caprazamycin biosynthesis and points out the importance of primary metabolism of the host cell for biosynthesis of natural products. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-022-01955-6.
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Zhou J, Wang J, Yao M, He J, Yang Y, Li X, Tan Z, Shi H, Zhu X, Tian B. An acetate-independent pathway for isopropanol production via HMG-CoA in Escherichia coli. J Biotechnol 2022; 359:29-34. [PMID: 36150604 DOI: 10.1016/j.jbiotec.2022.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 09/09/2022] [Accepted: 09/18/2022] [Indexed: 11/17/2022]
Abstract
Isopropanol has a good potential as a new fuel substitution. In the model biosynthesis pathway of isopropanol synthesis, acetoacetyl-CoA is converted to acetoacetate by acetoacetyl-CoA transferases, which requires an acetate molecule as a substrate. Herein, a novel isopropanol synthesis pathway based on mammalian ketone metabolic pathway was developed. In this pathway, acetoacetyl-CoA is condensed with acetyl-CoA to generate 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) by HMG-CoA synthase, and then catalyzed by HMG-CoA lyase to generate acetoacetate. This process is acetate-independent. Under the same experimental system using glycerol as carbon source, the E. coli strain MG::ISOP1 containing the novel pathway produced 11.7 times more isopropanol than the strain MG::ISOP0 containing the model pathway. The pta-ackA knockout mutant strain MG∆pta-ackA::ISOP1, which reduced the conversion of acetyl-CoA to acetate, further increased the production from 76 mg/L to 360 mg/L. In another strategy, knocking out atoDA to block the acetoacetate degradation pathway in strain MG∆atoDA::ISOP1 increased the production to 680 mg/L. By knocking out both of pta-ackA and atoDA, strain MGΔpta-ackAΔatoDA::ISOP1 produced 964 mg/L of isopropanol, which was 12.7 times that of MG::ISOP1. This study indicated that the novel pathway is competent for isopropanol synthesis, and provides a new perspective for biosynthesis of isopropanol.
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Affiliation(s)
- Jia Zhou
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China
| | - Jiahui Wang
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China
| | - Mengdie Yao
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China
| | - Junyi He
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China
| | - Yuxiang Yang
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China
| | - Xiangqian Li
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China
| | - Zhongbiao Tan
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China
| | - Hao Shi
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China
| | - Xiaoyan Zhu
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China
| | - Baoxia Tian
- Faculty of Life Science and Food Engineering, HuaiYin Institute of Technology, Huaian 223003, PR China; Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian 223003, PR China.
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Martínez-Alcantar L, Orozco G, Díaz-Pérez AL, Villegas J, Reyes-De la Cruz H, García-Pineda E, Campos-García J. Participation of Acyl-Coenzyme A Synthetase FadD4 of Pseudomonas aeruginosa PAO1 in Acyclic Terpene/Fatty Acid Assimilation and Virulence by Lipid A Modification. Front Microbiol 2021; 12:785112. [PMID: 34867927 PMCID: PMC8637051 DOI: 10.3389/fmicb.2021.785112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/19/2021] [Indexed: 12/03/2022] Open
Abstract
The pathogenic bacterium Pseudomonas aeruginosa possesses high metabolic versatility, with its effectiveness to cause infections likely due to its well-regulated genetic content. P. aeruginosa PAO1 has at least six fadD paralogous genes, which have been implicated in fatty acid (FA) degradation and pathogenicity. In this study, we used mutagenesis and a functional approach in P. aeruginosa PAO1 to determine the roles of the fadD4 gene in acyclic terpene (AT) and FA assimilation and on pathogenicity. The results indicate that fadD4 encodes a terpenoyl-CoA synthetase utilized for AT and FA assimilation. Additionally, mutations in fadD paralogs led to the modification of the quorum-sensing las/rhl systems, as well as the content of virulence factors pyocyanin, biofilm, rhamnolipids, lipopolysaccharides (LPS), and polyhydroxyalkanoates. In a Caenorhabditis elegans in vivo pathogenicity model, culture supernatants from the 24-h-grown fadD4 single mutant increased lethality compared to the PAO1 wild-type (WT) strain; however, the double mutants fadD1/fadD2, fadD1/fadD4, and fadD2/fadD4 and single mutant fadD2 increased worm survival. A correlation analysis indicated an interaction between worm death by the PAO1 strain, the fadD4 mutation, and the virulence factor LPS. Fatty acid methyl ester (FAME) analysis of LPS revealed that a proportion of the LPS and FA on lipid A were modified by the fadD4 mutation, suggesting that FadD4 is also involved in the synthesis/degradation and modification of the lipid A component of LPS. LPS isolated from the fadD4 mutant and double mutants fadD1/fadD4 and fadD2/fadD4 showed a differential behavior to induce an increase in body temperature in rats injected with LPS compared to the WT strain or from the fadD1 and fadD2 mutants. In agreement, LPS isolated from the fadD4 mutant and double mutants fadD1/fadD2 and fadD2/fadD4 increased the induction of IL-8 in rat sera, but IL1-β cytokine levels decreased in the double mutants fadD1/fadD2 and fadD1/fadD4. The results indicate that the fadD genes are implicated in the degree of pathogenicity of P. aeruginosa PAO1 induced by LPS-lipid A, suggesting that FadD4 contributes to the removal of acyl-linked FA from LPS, rendering modification in its immunogenic response associated to Toll-like receptor TLR4. The genetic redundancy of fadD is important for bacterial adaptability and pathogenicity over the host.
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Affiliation(s)
- Lorena Martínez-Alcantar
- Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico
| | - Gabriela Orozco
- Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico
| | - Alma Laura Díaz-Pérez
- Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico
| | - Javier Villegas
- Laboratorio de Interacción Suelo, Planta, Microorganismo, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico
| | - Homero Reyes-De la Cruz
- Laboratorio de Control Traduccional, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico
| | - Ernesto García-Pineda
- Laboratorio de Bioquímica y Biología Molecular, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico
| | - Jesús Campos-García
- Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mexico
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Wu C, Lan L, Li Y, Nie Z, Zeng R. The relationship between latex metabolism gene expression with rubber yield and related traits in Hevea brasiliensis. BMC Genomics 2018; 19:897. [PMID: 30526485 PMCID: PMC6288877 DOI: 10.1186/s12864-018-5242-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 11/12/2018] [Indexed: 11/20/2022] Open
Abstract
Background Expression patterns of many laticifer-specific gens are closely correlative with rubber yield of Hevea brasiliensis (para rubber tree). To unveil the mechanisms underlying the rubber yield, transcript levels of nine major latex metabolism-related genes, i.e., HMG-CoA synthase (HMGS), HMG-CoA reductase (HMGR), diphosphomevalonate decarboxylase (PMD), farnesyl diphosphate synthase (FPS), cis-prenyltransferase (CPT), rubber elongation factor (REF), small rubber particle protein (SRPP), dihydroxyacid dehydratase (DHAD) and actin depolymerizing factor (ADF), were dertermined, and the relationship between rubber yield with their expression levels was analysed. Results Except HbHMGR1, HbPMD and HbDHAD, most of these genes were predominantly expressed in latex, and bark tapping markedly elevated the transcript abundance of the analyzed genes, with the 7th tapping producing the greatest expression levels. Both ethephon (ETH) and methyl jasmonate (MeJA) stimulation greatly induced the expression levels of the examined genes, at least at one time point, except HbDHAD, which was unresponsive to MeJA. The genes’ expression levels, as well as the rubber yields and two yield characteristics differed significantly among the different genotypes examined. Additionally, the latex and dry rubber yields increased gradually but the dry rubber content did not. Rubber yields and/or yield characteristics were significantly positively correlated with HbCPT, HbFPS, HbHMGS, HbHMGR1 and HbDHAD expression levels, negatively correlated with that of HbREF, but not significantly correlated with HbPMD, HbSRPP and HbADF expression levels. In addition, during rubber production, significantly positive correlations existed between the expression level of HbPMD and the levels of HbREF and HbHMGR1, between HbSRPP and the levels of HbHMGS and HbHMGR1, and between HbADF and HbFPS. Conclusions The up-regulation of these genes might be related to the latex production of rubber trees under the stress of bark tapping and latex metabolism. The various correlations among the genes implied that there are differences in their synergic interactions. Thus, these nine genes might be related to rubber yield and yield-related traits in H. brasiliensis, and this work increases our understanding of their complex functions and how they are expressed in both high-and medium-yield rubber tree varieties and low-yield wild rubber tree germplasm. Electronic supplementary material The online version of this article (10.1186/s12864-018-5242-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chuntai Wu
- Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, 571737, People's Republic of China
| | - Li Lan
- Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, 571737, People's Republic of China.,College of Agriculture, Hainan University, Haikou, 570228, China
| | - Yu Li
- Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, 571737, People's Republic of China
| | - Zhiyi Nie
- Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, 571737, People's Republic of China
| | - Rizhong Zeng
- Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Danzhou, Hainan, 571737, People's Republic of China.
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Díaz-Pérez AL, Núñez C, Meza Carmen V, Campos-García J. The expression of the genes involved in leucine catabolism of Pseudomonas aeruginosa is controlled by the transcriptional regulator LiuR and by the CbrAB/Crc system. Res Microbiol 2018; 169:324-334. [PMID: 29787835 DOI: 10.1016/j.resmic.2018.05.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 05/09/2018] [Accepted: 05/15/2018] [Indexed: 12/29/2022]
Abstract
Pseudomonas aeruginosa metabolizes leucine through the leucine/isovalerate utilization pathway, whose enzymes are encoded in the liuRABCDE gene cluster (liu). In this study, we investigated the role of the LiuR protein in the liu cluster regulation. Our results indicated that liu expression is regulated at the transcriptional level by LiuR. Mobility shift assays using purified recombinant His-tagged LiuR showed that it was able to bind at the promoter region of liuR, in a dose-dependent manner. Results revealed that expression of the liu operon is subjected to carbon catabolite repression control (CCR); protein LiuD was strongly expressed in the presence of leucine, but it was repressed in the presence of glucose or succinate. Furthermore, this CCR control was dependent on LiuR as in the liuR- mutant the LiuD protein was strongly expressed in all the carbon sources tested. In agreement with this result, in the absence of the Crc protein, LiuD was expressed independently of the carbon source used, whereas in a cbrB- mutant its expression was severely impaired. The results indicated that the liu cluster is subjected to a coordinated transcriptional and translational regulation by the LiuR repressor and by the CbrAB/Crc system, respectively, in response to the available carbon source.
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Affiliation(s)
- Alma Laura Díaz-Pérez
- Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, 58030, Mexico.
| | - Cinthia Núñez
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, Cuernavaca, Morelos, 62210, Mexico.
| | - Victor Meza Carmen
- Laboratorio de Diferenciación Celular, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, 58030, Mexico.
| | - Jesús Campos-García
- Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacán, 58030, Mexico.
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Grishko VV, Nogovitsina YM, Ivshina IB. Bacterial transformation of terpenoids. RUSSIAN CHEMICAL REVIEWS 2014. [DOI: 10.1070/rc2014v083n04abeh004396] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Bacterial itaconate degradation promotes pathogenicity. Nat Chem Biol 2014; 10:371-7. [PMID: 24657929 DOI: 10.1038/nchembio.1482] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 02/14/2014] [Indexed: 12/30/2022]
Abstract
Itaconate (methylenesuccinate) was recently identified as a mammalian metabolite whose production is substantially induced during macrophage activation. This compound is a potent inhibitor of isocitrate lyase, a key enzyme of the glyoxylate cycle, which is a pathway required for the survival of many pathogens inside the eukaryotic host. Here we show that numerous bacteria, notably many pathogens such as Yersinia pestis and Pseudomonas aeruginosa, have three genes for itaconate degradation. They encode itaconate coenzyme A (CoA) transferase, itaconyl-CoA hydratase and (S)-citramalyl-CoA lyase, formerly referred to as CitE-like protein. These genes are known to be crucial for survival of some pathogens in macrophages. The corresponding enzymes convert itaconate into the cellular building blocks pyruvate and acetyl-CoA, thus enabling the bacteria to metabolize itaconate and survive in macrophages. The itaconate degradation and detoxification pathways of Yersinia and Pseudomonas are the result of convergent evolution. This work revealed a common persistence factor operating in many pathogenic bacteria.
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Campos-Garcia J, Diaz-Perez C, Diaz-Perez AL. Residues Asn214, Gln211, Glu219 and Gln221 contained in the subfamily 3 catalytic signature of the isocitrate lyase from Pseudomonas aeruginosa are involved in its catalytic and thermal properties. World J Microbiol Biotechnol 2013; 29:991-9. [PMID: 23338961 DOI: 10.1007/s11274-013-1258-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 01/08/2013] [Indexed: 11/26/2022]
Abstract
Isocitrate lyase, encoded by the aceA gene, plays an important role in the ability of Pseudomonas aeruginosa to grow on fatty acids, acetate, acyclic terpenes, and amino acids. Phylogenetic analysis indicated that the ICL superfamily is divided in two families: the ICL family, which includes five subfamilies, and the 2-methylisocitrate lyase (MICL) family. ICL from P. aeruginosa (ICL-Pa) was identified in a different ICL node (subfamily 3) than other Pseudomonas ICL enzymes (grouped in subfamily 1). Analysis also showed that psychrophilic bacteria are mainly grouped in ICL subfamily 3, whose ICL proteins contain the highly conserved catalytic pattern QIENQVSDEKQCGHQD. We performed site-directed mutagenesis, enzymatic activity, and structure modeling of conserved residues in mutated ICLs by using ICL-Pa as a model. Our results indicated that the N214 residue is essential for catalytic function, while mutating the Q211, E219, and Q221 residues impairs its catalytic and thermostability properties. Our findings suggest that conserved residues in the subfamily 3 signature of ICL-Pa play important roles in catalysis and thermostability and are likely associated with the catalytic loop structural conformation.
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Affiliation(s)
- Jesus Campos-Garcia
- Laboratorio de Biotecnologia, Instituto de Investigaciones Quimico-Biologicas, Universidad Michoacana de San Nicolas de Hidalgo, 58030 Morelia, Michoacan, Mexico.
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The 3-hydroxy-methylglutaryl coenzyme A lyase HCL1 is required for macrophage colonization by human fungal pathogen Histoplasma capsulatum. Infect Immun 2012. [PMID: 23184522 DOI: 10.1128/iai.00833-12] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Histoplasma capsulatum is a fungal respiratory pathogen that survives and replicates within the phagolysosome of macrophages. The molecular factors it utilizes to subvert macrophage antimicrobial defenses are largely unknown. Although the ability of H. capsulatum to prevent acidification of the macrophage phagolysosome is thought to be critical for intracellular survival, this hypothesis has not been tested since H. capsulatum mutants that experience decreased phagosomal pH have not been identified. In a screen to identify H. capsulatum genes required for lysis of bone marrow-derived macrophages (BMDMs), we identified an insertion mutation disrupting the H. capsulatum homolog of 3-hydroxy-methylglutaryl coenzyme A (HMG CoA) lyase (HCL1). In addition to its inability to lyse macrophages, the hcl1 mutant had a severe growth defect in BMDMs, indicating that HMG CoA lyase gene function is critical for macrophage colonization. In other organisms, HMG CoA lyase catalyzes the last step in the leucine catabolism pathway. In addition, both fungi and humans deficient in HMG CoA lyase accumulate acidic intermediates as a consequence of their inability to catabolize leucine. Consistent with observations in other organisms, the H. capsulatum hcl1 mutant was unable to grow on leucine as the major carbon source, caused acidification of its growth medium in vitro, and resided in an acidified vacuole within macrophages. Mice infected with the hcl1 mutant took significantly longer to succumb to infection than mice infected with the wild-type strain. Taken together, these data indicate the importance of Hcl1 function in H. capsulatum replication in the harsh growth environment of the macrophage phagosome.
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Co-expression of α and β subunits of the 3-methylcrotonyl-coenzyme A carboxylase from Pseudomonas aeruginosa. World J Microbiol Biotechnol 2011; 28:1185-91. [PMID: 22805839 DOI: 10.1007/s11274-011-0921-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 10/11/2011] [Indexed: 01/27/2023]
Abstract
Pseudomonas aeruginosa is a versatile bacterium that can grow using citronellol or leucine as sole carbon source. For both compounds the degradation pathways converge at the key enzyme 3-methylcrotonyl coenzyme-A carboxylase (MCCase). This enzyme is a complex formed by two subunits (α and β), encoded by the liuD and liuB genes, respectively; both are essential for enzyme function. Previously, both subunits had been separately expressed and then the complex re-constituted, however this methodology is laborious and produces low yield of active enzyme. In this work, the MCCase subunits were co-expressed in the same plasmid and purified in one step by affinity chromatography using the LiuD-His tag protein, interacting with the LiuB-S tag recombinant protein. The purified enzyme lost most of the activity within few hours of storage. The co-expressed subunits formed an (αβ)(4) complex that suffered a modification of its oligomerization state after storage, which probably contributed to the loss on activity observed. The recombinant MCCase enzyme presented optimum pH and temperature values of 9.0 and 30º C, respectively. Functionally, MCCase showed Michaelian kinetics behavior with a K(m) for its substrate and V(max) of 168 μM and 430 nmoles mg(-1)min(-1), respectively. The results suggest that the co-expression and co-purification of the subunits is a suitable procedure to obtain the active complex of the MCCase from Pseudomonas aeruginosa in a single step.
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Catabolism of citronellol and related acyclic terpenoids in pseudomonads. Appl Microbiol Biotechnol 2010; 87:859-69. [DOI: 10.1007/s00253-010-2644-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Revised: 04/23/2010] [Accepted: 04/23/2010] [Indexed: 10/19/2022]
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Förster-Fromme K, Jendrossek D. AtuR is a repressor of acyclic terpene utilization (Atu) gene cluster expression and specifically binds to two 13 bp inverted repeat sequences of the atuA-atuR intergenic region. FEMS Microbiol Lett 2010; 308:166-74. [PMID: 20487029 DOI: 10.1111/j.1574-6968.2010.02005.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The atuR-atuABCDEFGH gene cluster is essential for acyclic terpene utilization (Atu) in Pseudomonas aeruginosa and Pseudomonas citronellolis. The cluster encodes most proteins of the Atu pathway including the key enzyme, geranyl-CoA carboxylase. AtuR was identified as a repressor of the atu gene cluster expression by (1) amino acid similarity to TetR repressor family members, (2) constitutive expression of Atu proteins in the atuR insertion mutant and (3) specific binding of purified AtuR homodimers to the atuR-atuA intergenic region in electrophoretic mobility shift assay (EMSA). Two 13 bp inverted repeat sequences separated by 40 bp in the atuA operator/promoter region were identified to represent two sites of AtuR binding by EMSA. Changing of two or more bases within the inverted repeat sequences abolished the ability of AtuR to bind to its target. All EMSA experiments were sufficiently sensitive with ethidium bromide-stained DNA fragments after polyacrylamide gel electrophoresis.
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Chávez-Avilés M, Díaz-Pérez AL, Campos-García J. The bifunctional role of LiuE from Pseudomonas aeruginosa, displays additionally HIHG-CoA lyase enzymatic activity. Mol Biol Rep 2009; 37:1787-91. [PMID: 19597963 DOI: 10.1007/s11033-009-9611-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2009] [Accepted: 07/01/2009] [Indexed: 11/28/2022]
Abstract
Pseudomonas aeruginosa is able to utilize leucine/isovalerate and acyclic terpenes as sole carbon sources. Key enzymes which play an important role in these catabolic pathways are 3-hydroxy-3-methylglutaryl-coenzyme A (CoA) lyase (EC 4.1.3.4; HMG-CoA lyase) and the 3-hydroxy-3-isohexenylglutaryl-CoA lyase (EC 4.1.2.26; HIHG-CoA lyase), respectively. HMG-CoA lyase is encoded by the liuE gene while the gene for HIHG-CoA lyase remains unidentified. A mutant in the liuE gene was unable to utilize both leucine/isovalerate and acyclic terpenes indicates an involvement of liuE in both catabolic pathways (Chávez-Avilés et al. 2009, FEMS Microbiol Lett 296:117-123). The LiuE protein was purified as a His-tagged recombinant protein and in addition to show HMG-CoA lyase activity (Chávez-Avilés et al. 2009, FEMS Microbiol Lett 296:117-123), also displays HIHG-CoA lyase activity, indicating a bifunctional role in both the leucine/isovalerate and acyclic terpenes catabolic pathways.
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Affiliation(s)
- Mauricio Chávez-Avilés
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edif. B-3, Ciudad Universitaria, CP 58030, Morelia, Michoacán, Mexico
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