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Hu X, Bai Y, Fan TP, Zheng X, Cai Y. A novel type alanine dehydrogenase from Helicobacter aurati: Molecular characterization and application. Int J Biol Macromol 2020; 161:636-642. [PMID: 32534087 DOI: 10.1016/j.ijbiomac.2020.06.067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 06/06/2020] [Accepted: 06/08/2020] [Indexed: 01/07/2023]
Abstract
A novel alanine dehydrogenase (ADH; EC.1.4.1.1) with high pyruvate reduced activity was isolated from Helicobacter aurati and expressed in Escherichia coli BL21 (DE3). The optimum pH of the reduction and oxidation reaction were 8.0 and 9.0, respectively, and the optimum temperature was 55 °C. With pyruvate and alanine as substrates, the specific activity of HAADH1 were 268 U·mg-1 and 26 U·mg-1, respectively. HAADH1 had a prominent substrate specificity for alanine (Km = 2.23 mM, kcat/Km = 8.1 s-1·mM-1). In the reduction reaction, HAADH1 showed the highest substrate affinity for pyruvate (Km = 0.56 mM, kcat/Km = 364 s-1·mM-1). Compared to pyruvate, oxaloacetic acid, 2-ketobutyric acid, 3-fluoropyruvate, α-ketoglutaric acids, glyoxylic acid showed a residual activity of 93.30%, 8.93%, 5.62%, 2.57%, 2.51%, respectively. Phylogenetic tree analysis showed that this is a new type of ADH which have a low sequence similarity to available ADH reported in references. 3-Fluoropyruvate was effectively reduced to 3-fluoro-L-alanine by whole-cell catalysis.
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Affiliation(s)
- Xiaoxiang Hu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Yajun Bai
- College of Life Sciences, Northwest University, Xi'an, Shanxi 710069, China
| | - Tai-Ping Fan
- Department of Pharmacology, University of Cambridge, Cambridge CB2 1T, UK
| | - Xiaohui Zheng
- College of Life Sciences, Northwest University, Xi'an, Shanxi 710069, China.
| | - Yujie Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China.
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Roles of Alanine Dehydrogenase and Induction of Its Gene in Mycobacterium smegmatis under Respiration-Inhibitory Conditions. J Bacteriol 2018; 200:JB.00152-18. [PMID: 29712875 DOI: 10.1128/jb.00152-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 04/25/2018] [Indexed: 01/08/2023] Open
Abstract
Here we demonstrated that the inhibition of electron flux through the respiratory electron transport chain (ETC) by either the disruption of the gene for the major terminal oxidase (aa3 cytochrome c oxidase) or treatment with KCN resulted in the induction of ald encoding alanine dehydrogenase in Mycobacterium smegmatis A decrease in functionality of the ETC shifts the redox state of the NADH/NAD+ pool toward a more reduced state, which in turn leads to an increase in cellular levels of alanine by Ald catalyzing the conversion of pyruvate to alanine with the concomitant oxidation of NADH to NAD+ The induction of ald expression under respiration-inhibitory conditions in M. smegmatis is mediated by the alanine-responsive AldR transcriptional regulator. The growth defect of M. smegmatis by respiration inhibition was exacerbated by inactivation of the ald gene, suggesting that Ald is beneficial to M. smegmatis in its adaptation and survival under respiration-inhibitory conditions by maintaining NADH/NAD+ homeostasis. The low susceptibility of M. smegmatis to bcc1 complex inhibitors appears to be, at least in part, attributable to the high expression level of the bd quinol oxidase in M. smegmatis when the bcc1-aa3 branch of the ETC is inactivated.IMPORTANCE We demonstrated that the functionality of the respiratory electron transport chain is inversely related to the expression level of the ald gene encoding alanine dehydrogenase in Mycobacterium smegmatis Furthermore, the importance of Ald in NADH/NAD+ homeostasis during the adaptation of M. smegmatis to severe respiration-inhibitory conditions was demonstrated in this study. On the basis of these results, we propose that combinatory regimens including both an Ald-specific inhibitor and respiration-inhibitory antitubercular drugs such as Q203 and bedaquiline are likely to enable a more efficient therapy for tuberculosis.
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Della Bella C, Spinicci M, Grassi A, Bartalesi F, Benagiano M, Truthmann K, Tapinassi S, Troilo A, D’Elios S, Alnwaisri H, Shuralev E, Singh M, Bartoloni A, D’Elios MM. Novel M. tuberculosis specific IL-2 ELISpot assay discriminates adult patients with active or latent tuberculosis. PLoS One 2018; 13:e0197825. [PMID: 29856871 PMCID: PMC5983515 DOI: 10.1371/journal.pone.0197825] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 05/09/2018] [Indexed: 12/18/2022] Open
Abstract
Background Tuberculosis (TB) still is a major worldwide health problem, with 10.4 million new cases in 2016. Only 5–15% of people infected with M. tuberculosis develop TB disease while others remain latently infected (LTBI) during their lifetime. Thus, the absence of tests able to distinguish between latent infection and active tuberculosis is one of the major limits of currently available diagnostic tools. Methods A total of 215 patients were included in the study as active TB cases (n = 73), LTBI subjects (n = 88) and healthy persons (n = 54). Peripheral blood mononuclear cells (PBMCs) were isolated from each patient and the LIOSpot® TB anti-human IL-2 ELISpot assay was performed to test their proliferative response to M. tuberculosis antigens ESAT-6, CFP-10 and Ala-DH. Statistical analysis was performed to define the sensitivity and the specificity of the LIOSpot® TB kit for each antigen used and to set the best cut off value that enables discrimination between subjects with active TB or latent TB infection. Results Comparing the LIOSpot® TB results for each tested antigen between uninfected and infected subjects and between people with latent infection and active TB disease, the differences were significant for each antigen (p< 0.0001) but the ROC analysis demonstrated a high accuracy for the Ala-DH test only, with a cut off value of 12.5 SFC per million PBMCs and the Ala-DH ROC curve conferred a 96% sensitivity and 100% specificity to the test. For the ESAT-6 antigen, with a best cut off value of 71.25 SFC per million PBMCs, a sensitivity of 86% and specificity of 36% was obtained. Finally, the best cut off value for CFP-10 was 231.25 SFC per million PBMCs, with a sensitivity of 80% and a specificity of 54%. Thus, as for IGRA assays such as Quantiferon and T-Spot TB tests, ESAT-6 and CFP-10 are unable to distinguish LTBI from active TB when IL-2 is measured. On the contrary, the IL-2 production induced by Ala-DH, measured by LIOSpot® TB kit, shows high sensitivity and specificity for active TB disease. Conclusions This study demonstrates that the LIOSpot® TB test is a highly useful diagnostic tool to discriminate between latent TB infection and active tuberculosis in adults patients.
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Affiliation(s)
- Chiara Della Bella
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Michele Spinicci
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Alessia Grassi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Filippo Bartalesi
- Infectious and Tropical Diseases Unit, Florence Careggi University Hospital, Florence, Italy
| | - Marisa Benagiano
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Katja Truthmann
- LIONEX Diagnostics and Therapeutics GmbH, Braunschweig, Germany
| | - Simona Tapinassi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Arianna Troilo
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Sofia D’Elios
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Heba Alnwaisri
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Eduard Shuralev
- Institute of Environmental Sciences, Kazan Federal University, and Central Research Laboratory, Kazan State Medical Academy, and Federal Center for Toxicological, Radiation and Biological Safety, Kazan, Tatarstan, Russian Federation
| | - Mahavir Singh
- LIONEX Diagnostics and Therapeutics GmbH, Braunschweig, Germany
| | - Alessandro Bartoloni
- Infectious and Tropical Diseases Unit, Florence Careggi University Hospital, Florence, Italy
- * E-mail: (MMDE); (AB)
| | - Mario Milco D’Elios
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
- * E-mail: (MMDE); (AB)
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Awoniyi DO, Baumann R, Chegou NN, Kriel B, Jacobs R, Kidd M, Loxton AG, Kaempfer S, Singh M, Walzl G. Detection of a combination of serum IgG and IgA antibodies against selected mycobacterial targets provides promising diagnostic signatures for active TB. Oncotarget 2018; 8:37525-37537. [PMID: 28415587 PMCID: PMC5514927 DOI: 10.18632/oncotarget.16401] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 02/27/2017] [Indexed: 01/13/2023] Open
Abstract
Immunoglobulin G (IgG) based tests for the diagnosis of active tuberculosis (TB) disease often show a lack of specificity in TB endemic regions, which is mainly due to a high background prevalence of LTBI. Here, we investigated the combined performance of the responses of different Ig classes to selected mycobacterial antigens in primary healthcare clinic attendees with signs and symptoms suggestive of TB. The sensitivity and specificity of IgA, IgG and/or IgM to LAM and 7 mycobacterial protein antigens (ESAT-6, Tpx, PstS1, AlaDH, MPT64, 16kDa and 19kDa) and 2 antigen combinations (TUB, TB-LTBI) in the plasma of 63 individuals who underwent diagnostic work-up for TB after presenting with symptoms and signs compatible with possible active TB were evaluated. Active TB was excluded in 42 individuals of whom 21 has LTBI whereas active TB was confirmed in 21 patients of whom 19 had a follow-up blood draw at the end of 6-month anti-TB treatment. The leading single serodiagnostic markers to differentiate between the presence or absence of active TB were anti-16 kDa IgA, anti-MPT64 IgA with sensitivity and specificity of 90%/90% and 95%/90%, respectively. The combined use of 3 or 4 antibodies further improved this performance to accuracies above 95%. After successful completion of anti-TB treatment at month 6, the levels of 16 kDa IgA and 16 kDa IgM dropped significantly whereas LAM IgG and TB-LTBI IgG increased. These results show the potential of extending investigation of anti-tuberculous IgG responses to include IgM and IgA responses against selected protein and non-protein antigens in differentiating active TB from other respiratory diseases in TB endemic settings.
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Affiliation(s)
- Dolapo O Awoniyi
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Ralf Baumann
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa.,Institute for Occupational and Social Medicine, Aachen University of Technology, Aachen, Germany.,Lionex Diagnostics and Therapeutics, Braunschweig, Germany
| | - Novel N Chegou
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Belinda Kriel
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Ruschca Jacobs
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Martin Kidd
- Centre for Statistical Analysis, Stellenbosch University, Stellenbosch, South Africa
| | - Andre G Loxton
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | | | - Mahavir Singh
- Lionex Diagnostics and Therapeutics, Braunschweig, Germany
| | - Gerhard Walzl
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
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He G, Xu S, Wang S, Zhang Q, Liu D, Chen Y, Ju J, Zhao B. A conserved residue of l -alanine dehydrogenase from Bacillus pseudofirmus , Lys-73, participates in the catalytic reaction through hydrogen bonding. Enzyme Microb Technol 2018; 110:61-68. [DOI: 10.1016/j.enzmictec.2017.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 09/25/2017] [Accepted: 10/10/2017] [Indexed: 11/30/2022]
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Garcia-Morales L, Leon-Solis L, Monroy-Muñoz IE, Talavera-Paulin M, Serafin-López J, Estrada-Garcia I, Rivera-Gutierrez S, Cerna-Cortes JF, Helguera-Repetto AC, Gonzalez-Y-Merchand JA. Comparative proteomic profiles reveal characteristic Mycobacterium tuberculosis proteins induced by cholesterol during dormancy conditions. MICROBIOLOGY-SGM 2017; 163:1237-1247. [PMID: 28771131 DOI: 10.1099/mic.0.000512] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cholesterol has been reported to play an important role during Mycobacterium tuberculosis infection and during its dormant state inside the host. We present the determination of proteomic profiles of M. tuberculosis H37Rv in the presence of cholesterol as the sole carbon source under exponential growth and in two in vitro dormancy phases (NRP1 and NRP2). Using 2D-PAGE, we detected that M. tuberculosis expressed a high diversity of proteins in both exponential and non-replicative phases. We also found that cholesterol was involved in the overexpression of some proteins related to sulfur metabolism (CysA2), electron transport (FixB), cell wall synthesis (Ald), iron storage (BfrB), protein synthesis (Tig and EF-Tu) and dormancy maintenance (HspX and TB 31.7). According to our results we propose that proteins Ald, BfrB, FadA5 and TB31.7 are likely to play a fundamental role during in vitro dormancy of M. tuberculosis in the presence of cholesterol, helping to counteract its intracellular hostile microenvironment.
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Affiliation(s)
- Lazaro Garcia-Morales
- Departamento de Microbiologia, Escuela Nacional de Ciencias Biologicas (ENCB), Instituto Politecnico Nacional (IPN), Prolongacion Carpio y Plan de Ayala s/n, Ciudad de Mexico, 11340, Mexico
| | - Lizbel Leon-Solis
- Laboratorios de Biologicos y Reactivos de México S.A. de C.V., Birmex. Instituto Nacional de Virologia. Prolongacion Manuel Carpio No. 492, Delegacion Miguel Hidalgo 11340, Ciudad de Mexico, Mexico
| | - Irma E Monroy-Muñoz
- Departamento de Genetica y Genomica Humana, Torre de Investigacion, Instituto Nacional de Perinatologia Isidro Espinosa de los Reyes, SSA. Montes Urales 800, Lomas de Chapultepec, Ciudad de Mexico, 11000, Mexico
| | - Moises Talavera-Paulin
- Departamento de Inmunologia, Escuela Nacional de Ciencias Biologicas (ENCB), Instituto Politecnico Nacional (IPN), Prolongacion Carpio y Plan de Ayala s/n, Ciudad de Mexico, 11340, Mexico
| | - Jeanet Serafin-López
- Departamento de Inmunologia, Escuela Nacional de Ciencias Biologicas (ENCB), Instituto Politecnico Nacional (IPN), Prolongacion Carpio y Plan de Ayala s/n, Ciudad de Mexico, 11340, Mexico
| | - Iris Estrada-Garcia
- Departamento de Inmunologia, Escuela Nacional de Ciencias Biologicas (ENCB), Instituto Politecnico Nacional (IPN), Prolongacion Carpio y Plan de Ayala s/n, Ciudad de Mexico, 11340, Mexico
| | - Sandra Rivera-Gutierrez
- Departamento de Microbiologia, Escuela Nacional de Ciencias Biologicas (ENCB), Instituto Politecnico Nacional (IPN), Prolongacion Carpio y Plan de Ayala s/n, Ciudad de Mexico, 11340, Mexico
| | - Jorge F Cerna-Cortes
- Departamento de Microbiologia, Escuela Nacional de Ciencias Biologicas (ENCB), Instituto Politecnico Nacional (IPN), Prolongacion Carpio y Plan de Ayala s/n, Ciudad de Mexico, 11340, Mexico
| | - Addy C Helguera-Repetto
- Departamento de Inmunobioquimica, Torre de Investigacion, Instituto Nacional de Perinatologia Isidro Espinosa de los Reyes, SSA. Montes Urales 800, Lomas de Chapultepec, Ciudad de Mexico, 11000, Mexico
| | - Jorge A Gonzalez-Y-Merchand
- Departamento de Microbiologia, Escuela Nacional de Ciencias Biologicas (ENCB), Instituto Politecnico Nacional (IPN), Prolongacion Carpio y Plan de Ayala s/n, Ciudad de Mexico, 11340, Mexico
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Baumann R, Kaempfer S, Chegou NN, Nene NF, Veenstra H, Spallek R, Bolliger CT, Lukey PT, van Helden PD, Singh M, Walzl G. Serodiagnostic markers for the prediction of the outcome of intensive phase tuberculosis therapy. Tuberculosis (Edinb) 2013; 93:239-45. [DOI: 10.1016/j.tube.2012.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Revised: 09/13/2012] [Accepted: 09/20/2012] [Indexed: 01/15/2023]
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Maehara T, Hoshino T, Nakamura A. Characterization of three putative Lon proteases of Thermus thermophilus HB27 and use of their defective mutants as hosts for production of heterologous proteins. Extremophiles 2007; 12:285-96. [PMID: 18157502 DOI: 10.1007/s00792-007-0129-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Accepted: 11/22/2007] [Indexed: 11/29/2022]
Abstract
In the genome of a thermophilic bacterium, Thermus thermophilus HB27, three genes, TTC0418, TTC0746 and TTC1975, were annotated as ATP-dependent protease La (Lon). Sequence comparisons indicated that TTC0418 and TTC0746 showed significant similarities to bacterial LonA-type proteases, such as Escherichia coli Lon protease, especially in regions corresponding to domains for ATP-binding and hydrolysis, and for proteolysis, but TTC1975 exhibited a similarity only at the C-terminal proteolytic domain. The enzymatic analyses, using purified recombinant proteins produced by E. coli, revealed that TTC0418 and TTC0746 exhibited peptidase and protease activities against two synthetic peptides and casein, respectively, in an ATP-dependent manner, and at the same time, both the enzymes had significant ATPase activities in the presence of substrates. On the other hand, TTC1975 possessed a protease activity against casein, but addition of ATP did not enhance this activity. Moreover, a T. thermophilus mutant deficient in both TTC0418 and TTC0746 showed a similar growth characteristic to an E. coli lon mutant, i.e., a growth defect lag after a nutritional downshift. These results indicate that TTC0418 and TTC0746 are actually members of bacterial LonA-type proteases with different substrate specificities, whereas TTC1975 should not be classified as a Lon protease. Finally, the effects of mutations deficient in these proteases were assessed on production of several heterologous gene products from Pyrococcus horikoshii and Geobacillus stearothermophilus. It was shown that TTC0746 mutation was more effective in improving production than the other two mutations, especially for production of P. horikoshii alpha-mannosidase and G. stearothermophilus alpha-amylase, indicating that the TTC0746 mutant of T. thermophilus HB27 may be useful for production of heterologous proteins from thermophiles and hyperthermophiles.
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Affiliation(s)
- Tomoko Maehara
- Division of Integrative Environmental Sciences, Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
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Hutter B, Dick T. Increased alanine dehydrogenase activity during dormancy in Mycobacterium smegmatis. FEMS Microbiol Lett 1998; 167:7-11. [PMID: 9785446 DOI: 10.1111/j.1574-6968.1998.tb13200.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The aerobic fast-growing Mycobacterium smegmatis has, like its slow-growing pathogenic counterpart M. tuberculosis, the capability to adapt to anaerobiosis by shifting down to a drug resistant dormant state. Here, we report the identification of the first enzyme, L-alanine dehydrogenase, whose specific activity is increased during dormancy development in M. smegmatis. This mycobacterial enzyme activity was previously identified as the 40-kDa antigen in M. tuberculosis and shows a preference for the reductive amination of pyruvate to alanine at physiological pH. The determination of the temporal profile of alanine dehydrogenase activity during dormancy development showed that the activity stayed at a low baseline level during the initial aerobic exponential growth phase (0.7 mU mg-1 min-1). After termination of aerobic growth, alanine dehydrogenase activity increased rapidly 5-fold. As oxygen becomes more and more limiting, the enzyme activity declined until it reached a level about two-third that of the peak value. The strong induction immediately after deflection from aerobic growth suggests that alanine might be required for the adaptation from aerobic growth to anaerobic dormancy. As alanine synthesis is coupled to NADH oxidation, we propose that the induction of alanine dehydrogenase activity might also support the maintenance of the NAD pool when oxygen as a terminal electron acceptor becomes limiting.
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Affiliation(s)
- B Hutter
- Institute of Molecular and Cell Biology, Singapore, Singapore
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