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Prithviraj M, Kado T, Mayfield JA, Young DC, Huang AD, Motooka D, Nakamura S, Siegrist MS, Moody DB, Morita YS. Tuberculostearic Acid Controls Mycobacterial Membrane Compartmentalization. mBio 2023; 14:e0339622. [PMID: 36976029 PMCID: PMC10127668 DOI: 10.1128/mbio.03396-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 03/08/2023] [Indexed: 03/29/2023] Open
Abstract
The intracellular membrane domain (IMD) is a laterally discrete region of the mycobacterial plasma membrane, enriched in the subpolar region of the rod-shaped cell. Here, we report genome-wide transposon sequencing to discover the controllers of membrane compartmentalization in Mycobacterium smegmatis. The putative gene cfa showed the most significant effect on recovery from membrane compartment disruption by dibucaine. Enzymatic analysis of Cfa and lipidomic analysis of a cfa deletion mutant (Δcfa) demonstrated that Cfa is an essential methyltransferase for the synthesis of major membrane phospholipids containing a C19:0 monomethyl-branched stearic acid, also known as tuberculostearic acid (TBSA). TBSA has been intensively studied due to its abundant and genus-specific production in mycobacteria, but its biosynthetic enzymes had remained elusive. Cfa catalyzed the S-adenosyl-l-methionine-dependent methyltransferase reaction using oleic acid-containing lipid as a substrate, and Δcfa accumulated C18:1 oleic acid, suggesting that Cfa commits oleic acid to TBSA biosynthesis, likely contributing directly to lateral membrane partitioning. Consistent with this model, Δcfa displayed delayed restoration of subpolar IMD and delayed outgrowth after bacteriostatic dibucaine treatment. These results reveal the physiological significance of TBSA in controlling lateral membrane partitioning in mycobacteria. IMPORTANCE As its common name implies, tuberculostearic acid is an abundant and genus-specific branched-chain fatty acid in mycobacterial membranes. This fatty acid, 10-methyl octadecanoic acid, has been an intense focus of research, particularly as a diagnostic marker for tuberculosis. It was discovered in 1934, and yet the enzymes that mediate the biosynthesis of this fatty acid and the functions of this unusual fatty acid in cells have remained elusive. Through a genome-wide transposon sequencing screen, enzyme assay, and global lipidomic analysis, we show that Cfa is the long-sought enzyme that is specifically involved in the first step of generating tuberculostearic acid. By characterizing a cfa deletion mutant, we further demonstrate that tuberculostearic acid actively regulates lateral membrane heterogeneity in mycobacteria. These findings indicate the role of branched fatty acids in controlling the functions of the plasma membrane, a critical barrier for the pathogen to survive in its human host.
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Affiliation(s)
- Malavika Prithviraj
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Takehiro Kado
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Jacob A. Mayfield
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - David C. Young
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Annie D. Huang
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Daisuke Motooka
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Shota Nakamura
- Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - M. Sloan Siegrist
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Massachusetts, USA
| | - D. Branch Moody
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Yasu S. Morita
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
- Molecular and Cellular Biology Graduate Program, University of Massachusetts, Amherst, Massachusetts, USA
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Brandenburg J, Heyckendorf J, Marwitz F, Zehethofer N, Linnemann L, Gisch N, Karaköse H, Reimann M, Kranzer K, Kalsdorf B, Sanchez-Carballo P, Weinkauf M, Scholz V, Malm S, Homolka S, Gaede KI, Herzmann C, Schaible UE, Hölscher C, Reiling N, Schwudke D. Tuberculostearic Acid-Containing Phosphatidylinositols as Markers of Bacterial Burden in Tuberculosis. ACS Infect Dis 2022; 8:1303-1315. [PMID: 35763439 PMCID: PMC9274766 DOI: 10.1021/acsinfecdis.2c00075] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
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One-fourth of the
global human population is estimated to be infected
with strains of the Mycobacterium tuberculosis complex (MTBC), the causative agent of tuberculosis (TB). Using
lipidomic approaches, we show that tuberculostearic acid (TSA)-containing
phosphatidylinositols (PIs) are molecular markers for infection with
clinically relevant MTBC strains and signify bacterial burden. For
the most abundant lipid marker, detection limits of ∼102 colony forming units (CFUs) and ∼103 CFUs
for bacterial and cell culture systems were determined, respectively.
We developed a targeted lipid assay, which can be performed within
a day including sample preparation—roughly 30-fold faster than
in conventional methods based on bacterial culture. This indirect
and culture-free detection approach allowed us to determine pathogen
loads in infected murine macrophages, human neutrophils, and murine
lung tissue. These marker lipids inferred from mycobacterial PIs were
found in higher levels in peripheral blood mononuclear cells of TB
patients compared to healthy individuals. Moreover, in a small cohort
of drug-susceptible TB patients, elevated levels of these molecular
markers were detected at the start of therapy and declined upon successful
anti-TB treatment. Thus, the concentration of TSA-containing PIs can
be used as a correlate for the mycobacterial burden in experimental
models and in vitro systems and may prospectively also provide a clinically
relevant tool to monitor TB severity.
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Affiliation(s)
- Julius Brandenburg
- Division of Microbial Interface Biology, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Jan Heyckendorf
- Division of Clinical Infectious Disease, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Clinical Tuberculosis Center, 23845 Borstel, Germany
| | - Franziska Marwitz
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany
| | - Nicole Zehethofer
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany
| | - Lara Linnemann
- Division of Cellular Microbiology, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Nicolas Gisch
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Hande Karaköse
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany
| | - Maja Reimann
- Division of Clinical Infectious Disease, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Clinical Tuberculosis Center, 23845 Borstel, Germany
| | - Katharina Kranzer
- National Reference Center for Mycobacteria, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Barbara Kalsdorf
- Division of Clinical Infectious Disease, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Clinical Tuberculosis Center, 23845 Borstel, Germany
| | - Patricia Sanchez-Carballo
- Division of Clinical Infectious Disease, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Clinical Tuberculosis Center, 23845 Borstel, Germany
| | - Michael Weinkauf
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Verena Scholz
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Sven Malm
- Division of Molecular and Experimental Mycobacteriology, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Susanne Homolka
- Division of Molecular and Experimental Mycobacteriology, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Karoline I Gaede
- BioMaterialBank Nord, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Lung Research (DZL), Airway Research Center North (ARCN), Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Christian Herzmann
- Center for Clinical Studies, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Ulrich E Schaible
- German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany.,Division of Cellular Microbiology, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Christoph Hölscher
- German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany.,Division of Infection Immunology, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
| | - Norbert Reiling
- Division of Microbial Interface Biology, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany
| | - Dominik Schwudke
- Division of Bioanalytical Chemistry, Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany.,German Center for Infection Research, Thematic Translational Unit Tuberculosis, Partner Site Hamburg-Lübeck-Borstel-Riems, 23845 Borstel, Germany.,German Center for Lung Research (DZL), Airway Research Center North (ARCN), Research Center Borstel, Leibniz Lung Center, 23845 Borstel, Germany
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Fong TH, Shi W, Li S, Liu G, Ng CL, Jiang H. Tuberculostearic acid, a potential parameter for scoring system construction for tuberculous meningitis diagnosis. Int J Mycobacteriol 2021; 10:428-432. [PMID: 34916463 DOI: 10.4103/ijmy.ijmy_162_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Background This study aimed to validate the value of tuberculostearic acid (TBSA) whether it could implicate the existence of Mycobacterium tuberculosis (Mtb) and assist for the clinical diagnosis of tuberculous meningitis (TBM). Methods The patient's cerebrospinal fluid (CSF) specimen was collected through the lumbar puncture and detected for TBSA with gas chromatography/mass spectrometry. At the same time, gold standard tests, i.e., CSF direct culture, CSF smear microscopy, or nucleic acid amplification tests, for Mtb were routinely performed. Furthermore, we evaluated all patients by the Lancet consensus scoring system, which classifies suspected patients to "Definite (depend on gold standard results only)," "Probable (>10 pts without imaging or >12 pts with imaging information)," "Possible (6-9 pts without imaging or 6-11 pts with imaging)," and "Not (<6 pts or with alternative diagnoses)" TBM. Results In total, 140 patients were admitted for our study included 27 confirmed TBM patients and 50 TBSA-positive patients. Sensitivity (0.7407, confidence interval [CI] 95%: 0.5372-0.8889) and specificity (0.7345, CI 95%: 0.6432-0.8132) were calculated. The Lancet consensus scoring system was also applied to evaluate the possibility of TBM in suspected patients, finding that TBSA-positive patients showed a similar grouping distribution as the definite TBM patients. Conclusions Our study implicates that the prospective utilization of TBSA is worth combining into a scoring system for characterizing the features of Mtb, showing a great potential of TBM diagnosis by TBSA in future.
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Affiliation(s)
- Tsz Hei Fong
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Wangpan Shi
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Siyi Li
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Guanghui Liu
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Chung Lam Ng
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Haishan Jiang
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, China
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Lazy, dynamic or minimally recrudescent? On the elusive nature and location of the mycobacterium responsible for latent tuberculosis. Infection 2009; 37:87-95. [PMID: 19308316 DOI: 10.1007/s15010-009-8450-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Accepted: 01/26/2009] [Indexed: 01/21/2023]
Abstract
In the absence of symptoms characteristic of tuberculosis (TB), a condition termed clinical latency, diagnosis is currently impossible by detection of the microorganism itself and resorts to the demonstration of an immunological memory response to antigens of Mycobacterium tuberculosis (Mtb). Whether latency is synonymous to chronic persistent infection with viable Mtb in all instances has been difficult to establish. The physical and physiological state of Mtb during latency is much disputed: are organisms mostly dormant, in a nonreplicating state of persistence, and characterized by lipid inclusions and metabolic adaptation to hypoxia, or do they continue to replicate and sometimes even escape from the fringes of granulomatous lesions or alveolar epithelial cells into adjacent airways, thereby inducing recurring immune responses? The physical nature of Mtb during latency is important as it determines which antimicrobial agents may be used to kill it, which immunomodulating strategies (including post-exposure vaccines) may be appropriate to contain it, and which diagnostic measures may be most useful to discriminate latent from reactivating infection. Two major viewpoints exist: one argues that Mtb persists mostly in a lazy state within granulomatous lesions, but periodically recrudesces, and that there is considerable heterogeneity for different sites within the lesion and within the infected lung. Throughout latency, there is a dynamic immunological interplay between Mtb and the host, necessitating continuous recruitment of cells into the granuloma, and reactivation occurs when this dynamic cellular exchange becomes dysregulated. Another view holds that dormant Mtb reside within alveolar epithelial cells in the lung apices and in adipocytes, with reactivation being associated with the upregulation of resuscitation promoting factors within Mtb and the escape of newly dividing microorganisms into alveoli and bronchi in the form of lipid pneumonia. These views need not be mutually exclusive. However, if minimal intermittent recrudescence were to take place within the alveolar space, this would contradict the very definition of latency, which implies that no access of Mtb to the airways exists during latency.
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