1
|
Ghosh P, Barman A, Das Gupta SK. Induced expression of the zwf gene in the presence of glucose contributes to lowering of glucose 6-phosphate level and consequently reduction of growth rate of Mycobacterium smegmatis. MICROBIOLOGY-SGM 2021; 167. [PMID: 34236958 DOI: 10.1099/mic.0.001067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In Mycobacterium smegmatis (renamed Mycolicibacterium smegmatis), glucose 6-phosphate (G6P) level is exceptionally high as compared to other bacteria, E. coli for example. Earlier investigations have indicated that G6P protects M. smegmatis (Msm) against oxidative stress-inducing agents. G6P is a glycolytic intermediate formed either directly through the phosphorylation of glucose or indirectly via the gluconeogenic pathway. Its consumption is catalysed by several enzymes, one of which being the NADPH dependent G6P dehydrogenase (G6PDH) encoded by zwf (msmeg_0314). While investigating the extent to which the carbon sources glucose and glycerol influence Msm growth, we observed that intracellular concentration of G6P was lower in the former's presence than the latter. We could correlate this difference with that in the growth rate, which was higher in glycerol than glucose. We also found that lowering of G6P content in glucose-grown cells was triggered by the induced expression of zwf and the resultant increase in G6PDH activity. When we silenced zwf using CRISPR-Cas9 technology, we observed a significant rise in the growth rate of Msm. Therefore, we have found that depletion of G6P in glucose-grown cells due to increased G6PDH activity is at least one reason why the growth rate of Msm in glucose is less than glycerol. However, we could not establish a similar link-up between slow growth in glucose and lowering of G6P level in the case of Mycobacterium tuberculosis (Mtb). Mycobacteria, therefore, may have evolved diverse mechanisms to ensure that they use glycerol preferentially over glucose for their growth.
Collapse
Affiliation(s)
- Poulami Ghosh
- Department of Microbiology, Bose Institute, P-1/12 C.I.T. Scheme VIIM, Kolkata-700054, India
| | - Anik Barman
- Department of Microbiology, Bose Institute, P-1/12 C.I.T. Scheme VIIM, Kolkata-700054, India
| | - Sujoy K Das Gupta
- Department of Microbiology, Bose Institute, P-1/12 C.I.T. Scheme VIIM, Kolkata-700054, India
| |
Collapse
|
2
|
Tripartite Regulation of the glpFKD Operon Involved in Glycerol Catabolism by GylR, Crp, and SigF in Mycobacterium smegmatis. J Bacteriol 2019; 201:JB.00511-19. [PMID: 31570530 DOI: 10.1128/jb.00511-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/26/2019] [Indexed: 11/20/2022] Open
Abstract
The glpD (MSMEG_6761) gene encoding glycerol-3-phosphate dehydrogenase was shown to be crucial for M. smegmatis to utilize glycerol as the sole carbon source. The glpD gene likely forms the glpFKD operon together with glpF and glpK, encoding a glycerol facilitator and glycerol kinase, respectively. The gylR (MSMEG_6757) gene, whose product belongs to the IclR family of transcriptional regulators, was identified 182 bp upstream of glpF It was demonstrated that GylR serves as a transcriptional activator and is involved in the induction of glpFKD expression in the presence of glycerol. Three GylR-binding sites with the consensus sequence (GKTCGRC-N3-GYCGAMC) were identified in the upstream region of glpF by DNase I footprinting analysis. The presence of glycerol-3-phosphate was shown to decrease the binding affinity of GylR to the glpF upstream region with changes in the quaternary structure of GylR from tetramer to dimer. Besides GylR, cAMP receptor protein (Crp) and an alternative sigma factor, SigF, are also implicated in the regulation of glpFKD expression. Crp functions as a repressor, while SigF induces expression of glpFKD under energy-limiting conditions. In conclusion, we suggest here that the glpFKD operon is under the tripartite control of GylR, SigF, and Crp, which enables M. smegmatis to integrate the availability of glycerol, cellular energy state, and cellular levels of cAMP to exquisitely control expression of the glpFKD operon involved in glycerol metabolism.IMPORTANCE Using genetic approaches, we first revealed that glycerol is catabolized through the glycolytic pathway after conversion to dihydroxyacetone phosphate in two sequential reactions catalyzed by glycerol kinase (GlpK) and flavin adenine dinucleotide (FAD)-containing glycerol-3-phosphate dehydrogenase (GlpD) in M. smegmatis Our study also revealed that in addition to the GylR transcriptional activator that mediates the induction of the glpFKD operon by glycerol, the operon is regulated by SigF and Crp, which reflect the cellular energy state and cAMP level, respectively.
Collapse
|
3
|
Urease activity represents an alternative pathway for Mycobacterium tuberculosis nitrogen metabolism. Infect Immun 2012; 80:2771-9. [PMID: 22645285 DOI: 10.1128/iai.06195-11] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Urease represents a critical virulence factor for some bacterial species through its alkalizing effect, which helps neutralize the acidic microenvironment of the pathogen. In addition, urease serves as a nitrogen source provider for bacterial growth. Pathogenic mycobacteria express a functional urease, but its role during infection has yet to be characterized. In this study, we constructed a urease-deficient Mycobacterium tuberculosis strain and confirmed the alkalizing effect of the urease activity within the mycobacterium-containing vacuole in resting macrophages but not in the more acidic phagolysosomal compartment of activated macrophages. However, the urease-mediated alkalizing effect did not confer any growth advantage on M. tuberculosis in macrophages, as evidenced by comparable growth profiles for the mutant, wild-type (WT), and complemented strains. In contrast, the urease-deficient mutant exhibited impaired in vitro growth compared to the WT and complemented strains when urea was the sole source of nitrogen. Substantial amounts of ammonia were produced by the WT and complemented strains, but not with the urease-deficient mutant, which represents the actual nitrogen source for mycobacterial growth. However, the urease-deficient mutant displayed parental colonization profiles in the lungs, spleen, and liver in mice. Together, our data demonstrate a role for the urease activity in M. tuberculosis nitrogen metabolism that could be crucial for the pathogen's survival in nutrient-limited microenvironments where urea is the sole nitrogen source. Our work supports the notion that M. tuberculosis virulence correlates with its unique metabolic versatility and ability to utilize virtually any carbon and nitrogen sources available in its environment.
Collapse
|
4
|
Lanéelle MA, Launay A, Spina L, Marrakchi H, Laval F, Eynard N, Lemassu A, Tropis M, Daffé M, Etienne G. A novel mycolic acid species defines two novel genera of the Actinobacteria, Hoyosella and Amycolicicoccus. Microbiology (Reading) 2012; 158:843-855. [DOI: 10.1099/mic.0.055509-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Marie-Antoinette Lanéelle
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Anne Launay
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Lucie Spina
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Hedia Marrakchi
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Françoise Laval
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Nathalie Eynard
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Anne Lemassu
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Maryelle Tropis
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Mamadou Daffé
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| | - Gilles Etienne
- Université de Toulouse (Université Paul Sabatier Toulouse III), IPBS, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
- Centre National de la Recherche Scientifique (CNRS), Institut de Pharmacologie et de Biologie Structurale (IPBS, Unité Mixte de Recherche 5089) Département Mécanismes Moléculaires des Infections Mycobactériennes, 205 Route de Narbonne, BP 64182, F-31077 Toulouse, France
| |
Collapse
|
5
|
Cook GM, Berney M, Gebhard S, Heinemann M, Cox RA, Danilchanka O, Niederweis M. Physiology of mycobacteria. Adv Microb Physiol 2009; 55:81-182, 318-9. [PMID: 19573696 DOI: 10.1016/s0065-2911(09)05502-7] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mycobacterium tuberculosis is a prototrophic, metabolically flexible bacterium that has achieved a spread in the human population that is unmatched by any other bacterial pathogen. The success of M. tuberculosis as a pathogen can be attributed to its extraordinary stealth and capacity to adapt to environmental changes throughout the course of infection. These changes include: nutrient deprivation, hypoxia, various exogenous stress conditions and, in the case of the pathogenic species, the intraphagosomal environment. Knowledge of the physiology of M. tuberculosis during this process has been limited by the slow growth of the bacterium in the laboratory and other technical problems such as cell aggregation. Advances in genomics and molecular methods to analyze the M. tuberculosis genome have revealed that adaptive changes are mediated by complex regulatory networks and signals, resulting in temporal gene expression coupled to metabolic and energetic changes. An important goal for bacterial physiologists will be to elucidate the physiology of M. tuberculosis during the transition between the diverse conditions encountered by M. tuberculosis. This review covers the growth of the mycobacterial cell and how environmental stimuli are sensed by this bacterium. Adaptation to different environments is described from the viewpoint of nutrient acquisition, energy generation, and regulation. To gain quantitative understanding of mycobacterial physiology will require a systems biology approach and recent efforts in this area are discussed.
Collapse
Affiliation(s)
- Gregory M Cook
- Department of Microbiology and Immunology, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | | | | | | | | | | | | |
Collapse
|
6
|
Rajagopalan M, Atkinson MAL, Lofton H, Chauhan A, Madiraju MV. Mutations in the GTP-binding and synergy loop domains of Mycobacterium tuberculosis ftsZ compromise its function in vitro and in vivo. Biochem Biophys Res Commun 2005; 331:1171-7. [PMID: 15882999 DOI: 10.1016/j.bbrc.2005.03.239] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Indexed: 11/17/2022]
Abstract
The Mycobacterium tuberculosis FtsZ (FtsZ(TB)), unlike other eubacterial FtsZ proteins, shows slow GTP-dependent polymerization and weak GTP hydrolysis activities [E.L. White, L.J. Ross, R.C. Reynolds, L.E. Seitz, G.D. Moore, D.W. Borhani, Slow polymerization of Mycobacterium tuberculosis FtsZ, J. Bacteriol. 182 (2000) 4028-4034]. In an attempt to understand the biological significance of these findings, we created mutations in the GTP-binding (FtsZ(G103S)) and GTP hydrolysis (FtsZ(D210G)) domains of FtsZ and characterized the activities of the mutant proteins in vitro and in vivo. We show that FtsZ(G103S) is defective for binding to GTP and polymerization activities, and exhibited reduced GTPase activity whereas FtsZ(D210G) protein is proficient in binding to GTP, showing reduced polymerization activity but did not show any measurable GTPase activity. Visualization of FtsZ-GFP structures in ftsZ merodiploid strains by fluorescent microscopy revealed that FtsZ(D210G) is proficient in associating with Z-ring structures whereas FtsZ(G103S) is not. Finally, we show that Mycobacterium smegmatis ftsZ mutant strains producing corresponding mutant FtsZ proteins are non-viable indicating that mutant FtsZ proteins cannot function as the sole source for FtsZ, a result distinctly different from that reported for Escherichia coli. Together, our results indicate that optimal GTPase and polymerization activities of FtsZ are required to sustain cell division in mycobacteria and that the same conserved mutations in different bacterial species have distinct phenotypes.
Collapse
Affiliation(s)
- Malini Rajagopalan
- Biomedical Research, The University of Texas Health Center at Tyler, 11937 U.S. Hwy @ 271, Tyler, TX 75708-3154, USA.
| | | | | | | | | |
Collapse
|
7
|
Norton CD, LeChevallier MW, Falkinham JO. Survival of Mycobacterium avium in a model distribution system. WATER RESEARCH 2004; 38:1457-1466. [PMID: 15016522 DOI: 10.1016/j.watres.2003.07.008] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2002] [Accepted: 07/31/2003] [Indexed: 05/24/2023]
Abstract
A pilot study was designed to examine the impact of nutrient levels, pipe materials, and disinfection on the survival of M. avium in model drinking water distribution system biofilms. Studies showed that the survival of the organism was dependant upon a complex interaction between pipe surface, nutrient levels, and disinfectants. The findings showed that when no disinfection was applied, M. avium could be recovered from biofilms at nutrient levels of 50microg/L assimilable organic carbon. M. avium concentrations were lower on copper pipe surfaces following disinfection with free chlorine as compared to monochloramine. However, due to the interference of corrosion products, chloramination of iron pipe surfaces controlled M. avium levels better than free chlorine. These data demonstrate the significance of pipe materials on the survival of M. avium complex in biofilms. Elimination of competitive heterotrophic bacteria on copper pipe surfaces by the application of disinfection resulted in a population of nearly 100% M. avium. Heat treatment of M. avium biofilms was affected by the pipe composition and organic content of the water. Effluent temperatures >53 degrees C were required to control the occurrence of M. avium in the pipeline system. Although additional studies are required using improved detection methods, the results of this investigation suggest that reducing the biodegradable organic material in drinking water, control of corrosion, maintenance of an effective disinfectant residual, and management of hot water temperatures can help limit the occurrence of M. avium complex in drinking water biofilms.
Collapse
Affiliation(s)
- Cheryl D Norton
- American Water, Quality Control and Research Laboratory, 1115 South Illinois Street, Belleville, IL 62220, USA
| | | | | |
Collapse
|
8
|
Sung N, Collins MT. Variation in resistance of Mycobacterium paratuberculosis to acid environments as a function of culture medium. Appl Environ Microbiol 2003; 69:6833-40. [PMID: 14602647 PMCID: PMC262281 DOI: 10.1128/aem.69.11.6833-6840.2003] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2003] [Accepted: 08/01/2003] [Indexed: 12/12/2022] Open
Abstract
Acid resistance of Mycobacterium paratuberculosis was examined as a function of growth conditions (i.e., in vitro growth medium and pH). M. paratuberculosis was cultured in either fatty acid-containing medium (7H9-OADC) or glycerol-containing medium (WR-GD or 7H9-GD) at two culture pHs (pHs 6.0 and 6.8). Organisms produced in these six medium and pH conditions were then tested for resistance to acetate buffer at pHs 3, 4, 5, and 6 at 20 degrees C. A radiometric culture method (BACTEC) was used to quantify viable M. paratuberculosis cell data at various acid exposure times, and D values (decimal reduction times, or the times required to kill a 1-log(10) concentration of bacteria) were determined. Soluble proteins of M. paratuberculosis grown under all six conditions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to identify proteins that may be associated with acid resistance or susceptibility. The culture medium affected growth rate and morphology: thin floating sheets of cells were observed in 7H9-OADC versus confluent, thick, waxy, and wrinkled pellicles in WR-GD. Culture medium pH affected growth rate (which was highest at pH 6.0), but it had little or no effect on D values for M. paratuberculosis at any test pH. When grown in 7H9-OADC, M. paratuberculosis was more acid resistant at all test pHs (higher D values) than when grown in WR-GD. Glycerol appeared to be the culture medium component most responsible for lower levels of M. paratuberculosis acid resistance. When glycerol was substituted for OADC in the 7H9 medium, D values were significantly lower than those of 7H9-OADC-grown M. paratuberculosis and were approximately the same as those for M. paratuberculosis grown in WR-GD medium. Comparison of the SDS-PAGE protein profiles for M. paratuberculosis cultures grown in 7H9-OADC, WR-GD, or 7H9-GD medium revealed that increased expression of 34.2- and 14.0-kDa proteins was associated with higher levels of acid resistance of M. paratuberculosis grown in 7H9-OADC medium and that 56.6- and 41.3-kDa proteins were associated with lower levels of acid resistance. This is the first report showing that in vitro culture conditions significantly affect growth characteristics, acid resistance, and protein expression of M. paratuberculosis, and the results emphasize the importance of culture conditions for in vitro susceptibility studies.
Collapse
Affiliation(s)
- Nackmoon Sung
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | | |
Collapse
|
9
|
Greendyke R, Rajagopalan M, Parish T, Madiraju MVVS. Conditional expression of Mycobacterium smegmatis dnaA, an essential DNA replication gene. MICROBIOLOGY (READING, ENGLAND) 2002; 148:3887-3900. [PMID: 12480893 DOI: 10.1099/00221287-148-12-3887] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To begin to understand the role of Mycobacterium smegmatis dnaA in DNA replication, the dnaA gene was characterized at the genetic level. Western analyses revealed that DnaA accounts for approximately 0.18% of the total cellular protein during both the active and stationary growth periods. Expression of antisense dnaA RNA reduced viability, indicating that dnaA is an essential gene in replication. To further understand the role(s) of dnaA in replication, a conditionally expressing strain was constructed in which expression of dnaA was controlled by acetamide. Growth in the presence of 0.2% acetamide elevated the intracellular levels of DnaA and increased cell length, but did not affect viability. Visualization of DNA by fluorescence microscopy revealed that DnaA-overproducing cells were multinucleoidal, indicating a loss of synchrony between the replication and cell-division cycles. Withdrawal of acetamide resulted in the depletion of the intracellular levels of DnaA, reduced viability and gradually blocked DNA synthesis. Acetamide-starved cells were very filamentous, several times the size of the parent cells and showed either abnormal or multi-nucleoid morphology, indicating a blockage in cell-division events. The addition of acetamide to the starved cells restored their viability and shortened the lengths of their filaments back to the size of the parent cells. Thus, both increasing and decreasing the levels of DnaA have an effect on the cells, indicating that the level of DnaA is critical to the maintenance of coordination between DNA replication and cell division. It is concluded that DNA replication and cell-division processes in M. smegmatis are linked, and it is proposed that DnaA has a role in both of these processes.
Collapse
Affiliation(s)
- Rebecca Greendyke
- Biomedical Research, 11937 US Hwy@271, The University of Texas Health Center at Tyler, Tyler, TX-75708-3154, USA1
| | - Malini Rajagopalan
- Biomedical Research, 11937 US Hwy@271, The University of Texas Health Center at Tyler, Tyler, TX-75708-3154, USA1
| | - Tanya Parish
- Department of Medical Microbiology, Barts and the London, Queen Mary's School of Medicine and Dentistry, Turner St, Whitechapel, London E1 2AD, UK2
| | - Murty V V S Madiraju
- Biomedical Research, 11937 US Hwy@271, The University of Texas Health Center at Tyler, Tyler, TX-75708-3154, USA1
| |
Collapse
|
10
|
Abstract
It is likely that the incidence of infection by environmental opportunistic mycobacteria will continue to rise. Part of the rise will be caused by the increased awareness of these microbes as human pathogens and improvements in methods of detection and culture. Clinicians and microbiologists will continue to be challenged by the introduction of new species to the already long list of mycobacterial opportunists (see Table 3). The incidence of infection will also rise because an increasing proportion of the population is aging or subject to some type of immunosuppression. A second reason for an increase in the incidence of environmental mycobacterial infection is that these microbes are everywhere. They are present in water, biofilms, soil, and aerosols. They are natural inhabitants of the human environment, especially drinking water distribution systems. Thus, it is likely that everyone is exposed on a daily basis. It is likely that certain human activities can lead to selection of mycobacteria. Important lessons have been taught by study of cases of hypersensitivity pneumonitis associated with exposure to metalworking fluid. First, the implicated metalworking fluids contained water, the likely source of the mycobacteria. Second, the metalworking fluids contain hydrocarbons (e.g., pine oils) and biocides (e.g., morpholine) both of which are substrates for the growth of mycobacteria [53,193]. Third, outbreak of disease followed disinfection of the metalworking fluid [136,137]. Although the metalworking fluid was contaminated with microorganisms, it was only after disinfection that symptoms developed in the workers. Because mycobacteria are resistant to disinfectants, it is likely that the recovery of the mycobacteria from the metalworking fluid [137] was caused by their selection. Disinfection may also contribute, in part, to the persistence of M avium and M intracellulare in drinking water distribution systems [33,89,240]. M avium and M intracellulare are many times more resistant to chlorine, chloramine, chlorine dioxide, and ozone than are other water-borne microorganisms [141,236]. Consequently, disinfection of drinking water results in selection of mycobacteria. In the absence of competitors, even the slowly growing mycobacteria can grow in the distribution system [33]. It is likely that hypersensitivity pneumonitis in lifeguards and therapy pool attendants [139] is caused by a similar scenario.
Collapse
Affiliation(s)
- Joseph O Falkinham
- Department of Biology, Fralin Biotechnology Center, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0346, USA.
| |
Collapse
|
11
|
|
12
|
Besra GS, Morehouse CB, Rittner CM, Waechter CJ, Brennan PJ. Biosynthesis of mycobacterial lipoarabinomannan. J Biol Chem 1997; 272:18460-6. [PMID: 9218490 DOI: 10.1074/jbc.272.29.18460] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The mycobacterial lipoglycans, lipomannan (LM) and lipoarabinomannan (LAM), are potent immunomodulators in tuberculosis and leprosy. Little is known of their biosynthesis, other than being based on phosphatidylinositol (PI), and they probably originate in the phosphatidylinositol mannosides (PIMs; PIMans). A novel form of cell-free incubation involving in vitro and in situ labeling with GDP-[14C]Man of the polyprenyl-P-mannoses (C35/C50-P-Man) and the simpler PIMs of mycobacterial membranes, reisolation of the [14C]Man-labeled membranes, and in situ chase demonstrated the synthesis of a novel alpha(1-->6)-linked linear form of LM at the expense of the C35/C50-P-Man. There was little or no synthesis under these conditions of PIMan5 with its terminal alpha(1-->2)Man unit or the mature LM or LAM with copious alpha(1-->2)Man branching. Synthesis of the linear LM, but not of the simpler PIMan2, was susceptible to amphomycin, a lipopeptide antibiotic that specifically inhibits polyprenyl-P-requiring translocases. A mixture of P[3H]I and P[3H]IMan2 was incorporated into the linear LM, supporting other evidence that, like the PIMs, LM and LAM, it is a lipid-linked mannooligosaccharide and a new member of the mycobacterial glycosylphosphatidylinositol lipoglycan/glycolipid class. Hence, the simpler PIMs originate in PI and GDP-Man, but further growth of the linear backbone emanates from C35-/C50-P-Man and is amphomycin-sensitive. The origin of the alpha(1-->2)Man branches of mature PIMan5, LM, and LAM is not known at this time but is probably GDP-Man.
Collapse
Affiliation(s)
- G S Besra
- Department of Microbiology, Colorado State University, Fort Collins, Colorado 80523, USA
| | | | | | | | | |
Collapse
|
13
|
Corti S, Chevalier J, Cremieux A. Intracellular accumulation of norfloxacin in Mycobacterium smegmatis. Antimicrob Agents Chemother 1995; 39:2466-71. [PMID: 8585727 PMCID: PMC162966 DOI: 10.1128/aac.39.11.2466] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
To evaluate the intracellular accumulation of norfloxacin in mycobacteria, two methods were used with Mycobacterium smegmatis. A radiometric method (K. V. Cundy, C. E. Fasching, K. E. Willard, and L. R. Peterson, J. Antimicrob. Chemother. 28:491-497, 1991) was used without great modification, but the fluorometric method (P. G. S. Mortimer and L. J. V. Piddock, J. Antimicrob. Chemother. 28:639-653, 1991) was changed considerably. Indeed, adsorption of the quinolone to the bacterial surface was characterized by measuring the level of accumulation of 0 degree C. Taking into account the adsorption, the pH of the washing buffer was increased from 7.0 to 9.0 to improve the desorption of norfloxacin from the cell surface. Both the fluorometric method, with the technical improvement, and the radiometric method could be used to estimate the intracellular accumulation of norfloxacin, which resulted from the difference between the whole uptake measured at 37 degrees C and the adsorption measured at 0 degrees C. A total of 35 ng of norfloxacin per mg of cells (dry weight) penetrated into the M. smegmatis cell, and the steady state was achieved in 5 min. Use of inhibitors of the proton motive force revealed that transport of norfloxacin was energy independent. Thus, the same mechanisms of quinolone accumulation that occur in eubacteria seem to occur in mycobacteria, at least in M. smegmatis.
Collapse
Affiliation(s)
- S Corti
- Laboratoire de Microbiologie, Faculté de Pharmacie, Marseille, France
| | | | | |
Collapse
|
14
|
Kaneda K, Imaizumi S, Yano I. Distribution of C22-, C24- and C26-alpha-unit-containing mycolic acid homologues in mycobacteria. Microbiol Immunol 1995; 39:563-70. [PMID: 7494494 DOI: 10.1111/j.1348-0421.1995.tb02243.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
There are three mycolic acid homologues with C22-, C24- and C26-alpha-units in Mycobacterium. In order to reveal the composition and distribution of these homologues in each subclass and molecular species of mycolic acids and to compare them with the composition of constitutive non-polar fatty acids (free and bound forms), we have separated non-polar fatty acids and each subclass of mycolic acids from 21 mycobacterial species by thin-layer chromatography, and analyzed non-polar fatty acid methyl esters by gas chromatography (GC) and the cleavage products of methyl mycolate by pyrolysis GC. We further performed mass chromatographic analysis of trimethylsilyl (TMS) ether derivatives of mycolic acid methyl esters by monitoring [B-29]+ ions (loss of CHO from the alpha-branched-chain structure of mycolic acids) of m/z 426, 454 and 482 which are attributed to C22-, C24- and C26-alpha-units of TMS ether derivatives of methyl mycolates, respectively, (Kaneda, K. et al, J. Clin. Microbiol. 24: 1060-1070, 1986). By pyrolysis GC, C22:0, C24:0 and C26:0 fatty acid methyl esters generated by the C2-C3 cleavage of C22-, C24- and C26-alpha-unit-containing mycolic acid methyl esters, respectively, were detected. Their proportion was almost the same among subclasses of mycolic acids in every Mycobacterium and also similar to the proportion of constitutive non-polar C22:0, C24:0 and C26:0 fatty acids. By mass chromatography, the composition and distribution of C22- and C24-alpha-unit-containing homologues were revealed to be similar between alpha- and alpha'-mycolic acids in every Mycobacterium.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- K Kaneda
- Department of Bacteriology, Niigata University School of Medicine, Japan
| | | | | |
Collapse
|
15
|
Influence of the physiological state on the electric field mediated transformation efficiency of intact mycobacterial cells. J Electroanal Chem (Lausanne) 1991. [DOI: 10.1016/0022-0728(91)85633-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
16
|
Influence of the physiological state on the electric field mediated transformation efficiency of intact mycobacterial cells. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/0302-4598(91)87009-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
17
|
Lacave C, Quémard A, Lanéelle G. Cell-free synthesis of mycolic acids in Mycobacterium aurum: radioactivity distribution in newly synthesized acids and presence of cell wall in the system. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1045:58-68. [PMID: 2196087 DOI: 10.1016/0005-2760(90)90203-a] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Distribution of radiolabelling in different parts of the newly synthesized mycolic acids, by a cell-free system from Mycobacterium aurum previously described, is examined, [1-14C]acetate being the precursor. By oxidation cleavage of mycolic acids and examination of the fragments, it was shown that acetate was not uniformly incorporated into the molecule: the methyl terminal part was not labelled, while the central fragments--between unsaturations or between oxygenated functions (oxo or ester) and unsaturations--presented the major part of radioactivity, suggesting the elongation of a preformed compound that the cell-free extract was unable to synthesize. Moreover, the side-chain R2-CH2-COOH was only weakly labelled compared to the central fragments. Since non-hydroxylated fatty acids were not synthesized by the system, it is suggested that de novo C18 fatty acids may be elongated with C2 units by the cell-free extract into C22 fatty derivative, only a low level of labelling being recorded (two C2 units for all the molecule). A scheme is proposed to summarize the main results. Identification of meso-DAP which is a characteristic amino-acid of the peptidoglycan in Actinomycetes and analysis of the profiles of total fatty esters, demonstrated that the cell-free extract is partly constituted by fragments of the cell wall as has already been noticed by examination of micrographs of the extract.
Collapse
Affiliation(s)
- C Lacave
- Centre de Recherche de Biochimie et de Génétique Cellulaires, C.N.R.S., Université Paul Sabatier, Toulouse, France
| | | | | |
Collapse
|
18
|
Affiliation(s)
- P R Wheeler
- Department of Applied Biology, University of Hull, UK
| |
Collapse
|
19
|
Lacave C, Laneelle MA, Daffe M, Montrozier H, Laneelle G. Mycolic acid metabolic filiation and location in Mycobacterium aurum and Mycobacterium phlei. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 181:459-66. [PMID: 2714297 DOI: 10.1111/j.1432-1033.1989.tb14747.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Synchronous cultures of Mycobacterium aurum were used to prove a close relationship between cellular division and active synthesis of mycolic acids (characteristic long-chain 3-hydroxyacids, branched at position 2), confirming previous proposals. Mycolic acid biosynthesis was studied in two species (Mycobacterium phlei and M. aurum) each producing three types of mycolic acids: di-unsatured mycolates, oxomycolates and wax-ester mycolates (ester of dicarboxymycolic acid and 2-icosanol or 2-octadecanol). It was shown that unsaturated mycolates and oxomycolic acids were not directly related, whereas a metabolic filiation was confirmed between oxomycolate and wax ester mycolate: the latter derived from the former by a Baeyer-Villiger oxidation step, as has been proposed on the basis of structural considerations. By observing the labelling of the different mycolate pools in the cell, i.e. the organic-solvent-extractable fraction (essentially containing esters of trehalose and of glycerol) and the cell residue (assumed to be the cell-wall polymers), it was clear that oxomycolates and unsaturated mycolates appeared first in the extractable lipids, then in the wall-linked mycolates while wax-ester mycolates appeared first as wall-linked derivatives. Thus, it is proposed that mycolates could follow separate routes involving differently located enzymes to reach their complex forms either in extractable lipids or in the wall-linked arabino-galactan.
Collapse
Affiliation(s)
- C Lacave
- Centre de Recherche de Biochimie et Génétique Cellulaires, Université Paul Sabatier, Toulouse, France
| | | | | | | | | |
Collapse
|
20
|
Affiliation(s)
- T Rezanka
- Department of Biogenesis, Institute of Microbiology, Czechoslovak Academy of Sciences, Prague
| |
Collapse
|
21
|
Rezanka T, Cudlín J, Podojil M. Very-long-chain fatty acids from lower organism. Folia Microbiol (Praha) 1987; 32:149-76. [PMID: 3556353 DOI: 10.1007/bf02883244] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The qualitative occurrence and quantitative proportion of very-long-chain fatty acids (above C22), mainly in lower organisms and briefly in higher plants and animals is described.
Collapse
|
22
|
|
23
|
Haas CN, Meyer MA, Paller MS. The ecology of acid-fast organisms in water supply, treatment, and distribution systems. ACTA ACUST UNITED AC 1983. [DOI: 10.1002/j.1551-8833.1983.tb05089.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
24
|
Goldfine H. Lipids of Prokaryotes–Structure and Distribution. CURRENT TOPICS IN MEMBRANES AND TRANSPORT 1982. [DOI: 10.1016/s0070-2161(08)60307-x] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
25
|
Gadagkar R, Gopinathan KP. Growth ofMycobacterium smegmatis in minimal and complete media. J Biosci 1980. [DOI: 10.1007/bf02716867] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
26
|
Qureshi N, Takayama K, Schnoes H. Purification of C30-56 fatty acids from Mycobacterium tuberculosis H37Ra. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)86282-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
27
|
Asselineau C, Asselineau J. Trehalose-containing glycolipids. PROGRESS IN THE CHEMISTRY OF FATS AND OTHER LIPIDS 1978; 16:59-99. [PMID: 358271 DOI: 10.1016/0079-6832(78)90037-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|