Journal articles: 'Rv3852'

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Brodin, Priscille, Laleh Majlessi, Laurent Marsollier, Marien I. de Jonge, Daria Bottai, Caroline Demangel, Jason Hinds, et al. "Dissection of ESAT-6 System 1 of Mycobacterium tuberculosis and Impact on Immunogenicity and Virulence." Infection and Immunity 74, no. 1 (January 2006): 88–98. http://dx.doi.org/10.1128/iai.74.1.88-98.2006.

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ABSTRACT The dedicated secretion system ESX-1 of Mycobacterium tuberculosis encoded by the extended RD1 region (extRD1) assures export of the ESAT-6 protein and its partner, the 10-kDa culture filtrate protein CFP-10, and is missing from the vaccine strains M. bovis BCG and M. microti. Here, we systematically investigated the involvement of each individual ESX-1 gene in the secretion of both antigens, specific immunogenicity, and virulence. ESX-1-complemented BCG and M. microti strains were more efficiently engulfed by bone-marrow-derived macrophages than controls, and this may account for the enhanced in vivo growth of ESX-1-carrying strains. Inactivation of gene pe35 (Rv3872) impaired expression of CFP-10 and ESAT-6, suggesting a role in regulation. Genes Rv3868, Rv3869, Rv3870, Rv3871, and Rv3877 encoding an ATP-dependent chaperone and translocon were essential for secretion of ESAT-6 and CFP-10 in contrast to ppe68 Rv3873 and Rv3876, whose inactivation did not impair secretion of ESAT-6. A strict correlation was found between ESAT-6 export and the generation of ESAT-6 specific T-cell responses in mice. Furthermore, ESAT-6 secretion and specific immunogenicity were almost always correlated with enhanced virulence in the SCID mouse model. Only loss of Rv3865 and part of Rv3866 did not affect ESAT-6 secretion or immunogenicity but led to attenuation. This suggests that Rv3865/66 represent a new virulence factor that is independent from ESAT-6 secretion. The present study has allowed us to identify new aspects of the extRD1 region of M. tuberculosis and to explore its role in the pathogenesis of tuberculosis.

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Liu, Zhiqiang, Shuang Qie, Lili Li, Bingshui Xiu, Xiqin Yang, Zhenhua Dai, Xuhui Zhang, et al. "Identification of Novel RD1 Antigens and Their Combinations for Diagnosis of Sputum Smear−/Culture+ TB Patients." BioMed Research International 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/7486425.

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Rapid and accurate diagnosis of pulmonary tuberculosis (PTB) is an unresolved problem worldwide, especially for sputum smear− (S−) cases. In this study, five antigen genes including Rv3871, Rv3874, Rv3875, Rv3876, and Rv3879 were cloned fromMycobacterium tuberculosis(Mtb) RD1 and overexpressed to generate antigen fragments. These antigens and their combinations were investigated for PTB serodiagnosis. 298 serum samples were collected from active PTB patients, including 117 sputum smear+ (S+) and sputum culture+ (C+) cases, 101 S−/C+ cases, and 80 S−/C− cases. The serum IgG levels of the five antigens were measured by ELISA. Based on IgG levels, the sensitivity/specificity of Rv3871, Rv3874, Rv3875, Rv3876, and Rv3879 for PTB detection was 81.21%/74.74%, 63.09%/94.78%, 32.21%/87.37%, 62.42%/85.26%, and 83.56%/83.16%, respectively. Furthermore, the optimal result for PTB diagnosis was achieved by combining antigens Rv3871, Rv3876, and Rv3879. In addition, the IgG levels of Rv3871, Rv3876, and Rv3879 were found to be higher in S−/C+ PTB patients than in other PTB populations. More importantly, combination of the three antigens demonstrated superior diagnostic performance for both S−/C+ and S−/C− PTB. In conclusion, the combination of Rv3871, Rv3876, and Rv3879 induced higher IgG response in sputum S−/C+ PTB patients and represents a promising biomarker combination for diagnosing of PTB.

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Garg, Rajni, Chinmay Anand, Sohini Ganguly, Sandhya Rao, Rinkee Verma, and Valakunja Nagaraja. "Direct Interaction of Polar Scaffolding Protein Wag31 with Nucleoid-Associated Protein Rv3852 Regulates Its Polar Localization." Cells 10, no. 6 (June 20, 2021): 1558. http://dx.doi.org/10.3390/cells10061558.

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Rv3852 is a unique nucleoid-associated protein (NAP) found exclusively in Mycobacterium tuberculosis (Mtb) and closely related species. Although annotated as H-NS, we showed previously that it is very different from H-NS in its properties and is distinct from other NAPs, anchoring to cell membrane by virtue of possessing a C-terminal transmembrane helix. Here, we investigated the role of Rv3852 in Mtb in organizing architecture or synthesis machinery of cell wall by protein–protein interaction approach. We demonstrated a direct physical interaction of Rv3852 with Wag31, an important cell shape and cell wall integrity determinant essential in Mtb. Wag31 localizes to the cell poles and possibly acts as a scaffold for cell wall synthesis proteins, resulting in polar cell growth in Mtb. Ectopic expression of Rv3852 in M. smegmatis resulted in its interaction with Wag31 orthologue DivIVAMsm. Binding of the NAP to Wag31 appears to be necessary for fine-tuning Wag31 localization to the cell poles, enabling complex cell wall synthesis in Mtb. In Rv3852 knockout background, Wag31 is mislocalized resulting in disturbed nascent peptidoglycan synthesis, suggesting that the NAP acts as a driver for localization of Wag31 to the cell poles. While this novel association between these two proteins presents one of the mechanisms to structure the elaborate multi-layered cell envelope of Mtb, it also exemplifies a new function for a NAP in mycobacteria.

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Werlang, Isabel C. R., Cristopher Z. Schneider, Jordana D. Mendonça, Mario S. Palma, Luiz A. Basso, and Diógenes S. Santos. "Identification of Rv3852 as a nucleoid-associated protein in Mycobacterium tuberculosis." Microbiology 155, no. 8 (August 1, 2009): 2652–63. http://dx.doi.org/10.1099/mic.0.030148-0.

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Tuberculosis remains the major cause of mortality due to a bacterial pathogen, Mycobacterium tuberculosis. The molecular mechanisms of infection and persistence have not been completely elucidated for this pathogen. Studies involving nucleoid-associated proteins (NAPs), which have been related to the control and influence of virulence genes in pathogenic bacteria, can help unveil the virulence process of M. tuberculosis. Here, we describe the initial characterization of an ORF for an M. tuberculosis putative NAP. The Rv3852 gene was cloned and expressed, and its product purified to homogeneity. A qualitative protein–DNA binding assay was carried out by gel-retardation and the protein affinity for specific DNA sequences was assessed quantitatively by surface plasmon resonance (SPR). A stoichiometry of 10 molecules of monomeric protein per molecule of DNA was determined. The monophasic apparent dissociation rate constant values increased to a saturable level as a function of protein concentration, yielding two limiting values for the molecular recognition of proU2 DNA. A protein–DNA binding mechanism is proposed. In addition, functional complementation studies with an Escherichia coli hns mutant reinforce the likelihood that the Rv3852 protein represents a novel NAP in M. tuberculosis.

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Zhao, Nan, Mingna Sun, Kristin Burns-Huang, Xiuju Jiang, Yan Ling, Crystal Darby, Sabine Ehrt, Gang Liu, and Carl Nathan. "Identification of Rv3852 as an Agrimophol-Binding Protein in Mycobacterium tuberculosis." PLOS ONE 10, no. 5 (May 15, 2015): e0126211. http://dx.doi.org/10.1371/journal.pone.0126211.

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Liu, Xiao-Qing, Davinder Dosanjh, Hansa Varia, Katie Ewer, Paul Cockle, Geoffrey Pasvol, and Ajit Lalvani. "Evaluation of T-Cell Responses to Novel RD1- and RD2-Encoded Mycobacterium tuberculosis Gene Products for Specific Detection of Human Tuberculosis Infection." Infection and Immunity 72, no. 5 (May 2004): 2574–81. http://dx.doi.org/10.1128/iai.72.5.2574-2581.2004.

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ABSTRACT The tuberculin skin test for diagnosing Mycobacterium tuberculosis infection suffers from antigenic cross-reactivity of purified protein derivative with BCG, resulting in poor specificity in BCG-vaccinated populations. Comparative genomics has identified several genetic regions in M. tuberculosis and M. bovis that are deleted in M. bovis BCG. Proteins encoded in these regions will form the basis of new specific T-cell-based blood tests that do not cross-react with BCG, but only two, early secretory antigen target 6 and culture filtrate protein 10, have been studied in detail in humans. We investigated four novel gene products, encoded by RD2 (Rv1989c) and RD1 (Rv3873, Rv3878, and Rv3879c), that are absent from most or all of the vaccine strains of BCG, respectively. Sixty-seven overlapping peptides were tested in ex vivo gamma interferon enzyme-linked immunospot assays in 49 patients with culture-confirmed tuberculosis and 38 healthy BCG-vaccinated donors. Forty-five percent (95% confidence interval [CI], 31 to 57%) and 53% (95% CI, 39 to 67%) of the tuberculosis patients responded to Rv3879c and Rv3873, respectively, identifying these proteins as major M. tuberculosis T-cell antigens in humans, while 35 and 25% of the patients responded to Rv3878 and Rv1989c, respectively. Of the 38 BCG-vaccinated donors, 1 (2.6%) responded to peptides from Rv3878 and Rv3879c, 3 (7.9%) responded to Rv3873, and none responded to Rv1989c. Exclusion of cross-reactive peptides encoded in conserved motifs of Rv3873, a PPE family member, increased its specificity to 97.4%. The high specificity of Rv3879c peptides and nonconserved Rv3873 sequences, together with their moderate sensitivity in tuberculosis patients, identifies these peptides as candidates for inclusion in new T-cell-based tests for M. tuberculosis infection.

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Cockle, P. J., S. V. Gordon, A. Lalvani, B. M. Buddle, R. G. Hewinson, and H. M. Vordermeier. "Identification of Novel Mycobacterium tuberculosis Antigens with Potential as Diagnostic Reagents or Subunit Vaccine Candidates by Comparative Genomics." Infection and Immunity 70, no. 12 (December 2002): 6996–7003. http://dx.doi.org/10.1128/iai.70.12.6996-7003.2002.

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ABSTRACT An independent review for the British government has concluded that the development of a cattle vaccine against Mycobacterium bovis holds the best long-term prospects for tuberculosis control in British herds. The development of complementary diagnostic tests to differentiate between vaccinated and infected animals is necessary to allow the continuation of test-and-slaughter-based control policies alongside vaccination. Vaccination with M. bovis bacillus Calmette-Guérin (BCG), the only available vaccine, results in tuberculin purified protein derivative sensitivity and has shown varying vaccine efficacies in cattle. Thus, identification of more-specific reagents to distinguish between vaccination and infection, as well as the identification of subunit vaccine candidates for improved tuberculosis vaccines, is a research priority. In the present study, we applied comparative genomics to identify M. bovis-Mycobacterium tuberculosis antigens whose genes had been deleted in BCG Pasteur. In total, 13 open reading frames (ORFs) from the RD1, RD2, and RD14 regions of the M. tuberculosis genome were selected. Pools of overlapping peptides spanning these ORFs were tested in M. bovis-infected (n = 22), BCG-vaccinated (n = 6), and unvaccinated (n = 10) control cattle. All were recognized in infected cattle, with responder frequencies varying between 16 and 86%. In particular, eight highly immunogenic antigens were identified whose potentials as diagnostic reagents or as subunit vaccines warrant further study (Rv1983, Rv1986, Rv3872, Rv3873, Rv3878, Rv3879c, Rv1979c, and Rv1769).

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Tiwari, Bhavana, Amarendranath Soory, and Tirumalai R. Raghunand. "An immunomodulatory role for theMycobacterium tuberculosisregion of difference 1 locus proteins PE35 (Rv3872) and PPE68 (Rv3873)." FEBS Journal 281, no. 6 (February 12, 2014): 1556–70. http://dx.doi.org/10.1111/febs.12723.

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Demangel, Caroline, Priscille Brodin, Paul J. Cockle, Roland Brosch, Laleh Majlessi, Claude Leclerc, and Stewart T. Cole. "Cell Envelope Protein PPE68 Contributes to Mycobacterium tuberculosis RD1 Immunogenicity Independently of a 10-Kilodalton Culture Filtrate Protein and ESAT-6." Infection and Immunity 72, no. 4 (April 2004): 2170–76. http://dx.doi.org/10.1128/iai.72.4.2170-2176.2004.

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ABSTRACT The protective efficacy of Mycobacterium bovis BCG can be markedly augmented by stable integration of Mycobacterium tuberculosis genomic region RD1. BCG complemented with RD1 (BCG::RD1) encodes nine additional proteins. Among them, 10-kDa culture filtrate protein (CFP-10) and ESAT-6 (6-kDa early secreted antigenic target) are low-molecular-weight proteins that induce potent Th1 responses. Using pools of synthetic peptides, we have examined the potential immunogenicity of four other RD1 products (PE35, PPE68, Rv3878, and Rv3879c). PPE68, the protein encoded by rv3873, was the only one to elicit gamma interferon (IFN-γ)-producing cells in C57BL/6 mice infected with M. tuberculosis. Anti-PPE68 T cells were predominantly raised against an epitope mapped in the N-terminal end of the protein. Importantly, inactivation of rv3873 in BCG::RD1 did not modify CFP-10 and ESAT-6 secretion. Moreover, the generation of IFN-γ responses to these antigens following immunization with BCG::RD1 was independent of PPE68 expression. Taken together, these results show that PPE68 is an immunogenic product of the RD1 region, which does not interfere with the secretion and immunogenicity of CFP-10 and ESAT-6.

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Meniche, Xavier, Cécile Labarre, Célia de Sousa-d'Auria, Emilie Huc, Françoise Laval, Marielle Tropis, Nicolas Bayan, et al. "Identification of a Stress-Induced Factor of Corynebacterineae That Is Involved in the Regulation of the Outer Membrane Lipid Composition." Journal of Bacteriology 191, no. 23 (October 2, 2009): 7323–32. http://dx.doi.org/10.1128/jb.01042-09.

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ABSTRACT Corynebacterineae are gram-positive bacteria that possess a true outer membrane composed of mycolic acids and other lipids. Little is known concerning the modulation of mycolic acid composition and content in response to changes in the bacterial environment, especially temperature variations. To address this question, we investigated the function of the Rv3802c gene, a gene conserved in Corynebacterineae and located within a gene cluster involved in mycolic acid biosynthesis. We showed that the Rv3802 ortholog is essential in Mycobacterium smegmatis, while its Corynebacterium glutamicum ortholog, NCgl2775, is not. We provided evidence that the NCgl2775 gene is transcriptionally induced under heat stress conditions, and while the corresponding protein has no detectable activity under normal growth conditions, the increase in its expression triggers an increase in mycolic acid biosynthesis concomitant with a decrease in phospholipid content. We demonstrated that these lipid modifications are part of a larger outer membrane remodeling that occurs in response to exposure to a moderately elevated temperature (42°C). In addition to showing an increase in the ratio of saturated corynomycolates to unsaturated corynomycolates, our results strongly suggested that the balance between mycolic acids and phospholipids is modified inside the outer membrane following a heat challenge. Furthermore, we showed that these lipid modifications help the bacteria to protect against heat damage. The NCgl2775 protein and its orthologs thus appear to be a protein family that plays a role in the regulation of the outer membrane lipid composition of Corynebacterineae under stress conditions. We therefore propose to name this protein family the envelope lipids regulation factor (ElrF) family.

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Korch, Shaleen B., Heidi Contreras, and Josephine E. Clark-Curtiss. "Three Mycobacterium tuberculosis Rel Toxin-Antitoxin Modules Inhibit Mycobacterial Growth and Are Expressed in Infected Human Macrophages." Journal of Bacteriology 191, no. 5 (December 29, 2008): 1618–30. http://dx.doi.org/10.1128/jb.01318-08.

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ABSTRACT Mycobacterium tuberculosis protein pairs Rv1246c-Rv1247c, Rv2865-Rv2866, and Rv3357-Rv3358, here named RelBE, RelFG, and RelJK, respectively, were identified based on homology to the Escherichia coli RelBE toxin:antitoxin (TA) module. In this study, we have characterized each Rel protein pair and have established that they are functional TA modules. Overexpression of individual M. tuberculosis rel toxin genes relE, relG, and relK induced growth arrest in Mycobacterium smegmatis; a phenotype that was completely reversible by expression of their cognate antitoxin genes, relB, relF, and relJ, respectively. We also provide evidence that RelB and RelE interact directly, both in vitro and in vivo. Analysis of the genetic organization and regulation established that relBE, relFG, and relJK form bicistronic operons that are cotranscribed and autoregulated, in a manner unlike typical TA modules. RelB and RelF act as transcriptional activators, inducing expression of their respective promoters. However, RelBE, RelFG, and RelJK (together) repress expression to basal levels of activity, while RelJ represses promoter activity altogether. Finally, we have determined that all six rel genes are expressed in broth-grown M. tuberculosis, whereas relE, relF, and relK are expressed during infection of human macrophages. This is the first demonstration of M. tuberculosis expressing TA modules in broth culture and during infection of human macrophages.

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Choi, Seunga, Han-Gyu Choi, Ki-Won Shin, Yong Woo Back, Hye-Soo Park, Jae Hwi Lee, and Hwa-Jung Kim. "Mycobacterium tuberculosisProtein Rv3841 Activates Dendritic Cells and Contributes to a T Helper 1 Immune Response." Journal of Immunology Research 2018 (2018): 1–13. http://dx.doi.org/10.1155/2018/3525302.

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The attenuated vaccineMycobacterium bovisBCG (Bacille Calmette Guerin) has limited protective efficacy against TB. The development of more effective TB vaccines has focused on the mycobacterial antigens that cause strong T helper 1 (Th1) responses. Mtb protein Rv3841 (bacterioferritin B; BfrB) is known to play a crucial role in the growth of Mtb. Nonetheless, it is unclear whether Rv3841 can induce protective immunity against Mtb. Here, we studied the action of Rv3841 in maturation of dendritic cells (DCs) and its engagement in the development of T-cell immunity. We found that Rv3841 functionally activated DCs by upregulating costimulatory molecules and increased secretion of proinflammatory cytokines. Activation of DCs by Rv3841 was mediated by Toll-like receptor 4 (TLR4), followed by triggering of mitogen-activated protein kinase and nuclear factor-κB signaling pathways. In addition, Rv3841-matured DCs effectively proliferated and polarized Th1 immune response of naïve CD4+and CD8+T-cells. Moreover, Rv3841 specifically caused the expansion of CD4+CD44highCD62LlowT-cells from Mtb-infected mice; besides, the T-cells activated by Rv3841-matured DCs inhibited intracellular mycobacterial growth. Our data suggest that Rv3841 induces DC maturation and protective immune responses, a finding that may provide candidate of effective TB vaccines.

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Chaitra, M. G., M. S. Shaila, and R. Nayak. "Characterization of T-cell immunogenicity of two PE/PPE proteins of Mycobacterium tuberculosis." Journal of Medical Microbiology 57, no. 9 (September 1, 2008): 1079–86. http://dx.doi.org/10.1099/jmm.0.47565-0.

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The PE and PPE proteins of Mycobacterium tuberculosis form a source of antigenic variation among different strains of this bacterium. Two of the PE_PGRS protein-encoding genes, rv3812 and rv3018c, are expressed in pathogenic mycobacteria and are implicated, respectively, in the persistence of the organism in macrophages and in virulence. Peptides derived from these proteins have been predicted to bind major histocompatibility complex (MHC) class I with high affinity on the basis of immunoinformatics analysis, suggesting a possible role for these proteins in antimycobacterial immunity. In the present work, using DNA constructs containing the rv3812 and rv3018c genes of M. tuberculosis, the immunogenicity of these proteins was demonstrated in BALB/c mice. Immunization with either DNA construct induced a significant number of CD8+-type T cells and a strong Th1-type response, with high gamma interferon (IFN-γ) and low interleukin-4 responses. Three nonameric peptides of Rv3812 and two of Rv3018c elicited a strong T-cell response in an MHC-restricted manner. An epitope-specific response was demonstrated by the lysis of peptide-pulsed antigen-presenting cells, release of perforin and IFN-γ production. Experimentally, these peptides bound with high affinity to MHC H-2Kd and showed low dissociation rates of peptide–MHC complexes. This study suggests that the identified T-cell epitopes may contribute to immunity against tuberculosis if included in a vaccine.

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Lindestam Arlehamn, Cecilia, Bianca Mothe, Courtney Dow, Myles Dillon, Roger Wiseman, Patrick Bohn, Julie Karl, et al. "The Mycobacterium tuberculosis-specific CD4 T cell immune repertoire in rhesus macaques overlaps with human responses (MPF2P.752)." Journal of Immunology 194, no. 1_Supplement (May 1, 2015): 63.11. http://dx.doi.org/10.4049/jimmunol.194.supp.63.11.

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Abstract Animal models to study the process of TB pathogenesis and vaccine development are of importance. NHP models, especially Rhesus macaques, are attractive because of available resources to evaluate their immunogenetic backgrounds and the aerosol model closely mimics the human infection route. In this study, we characterized the MHC immunogenetic background of a cohort of animals that have been vaccinated and/or infected with Mtb, defining 54 new immunodominant CD4 T cell epitopes using IFNγ ELISPOTs with antigens utilized in human clinical trials. Antigens which are immunodominant in humans are also immunodominant in rhesus macaques, including Rv3875 (ESAT-6) and Rv3874 (CFP10). Interestingly, the shared responses were not due to common ancestry or inbreeding upon identifying MHC alleles. Instead, the results indicate promiscuous binding, which is the first account of this phenomenon in the rhesus macaque TB model of infection. These results suggest that while the CD4 response of NHPs to TB is broad and heterogeneous, epitope sets can be defined to broadly follow and characterize these responses in genetically heterogeneous NHP animal cohorts. To our knowledge, this is the first comprehensive epitope identification effort for non-human primates. We reveal a profound repertoire overlap between epitopes recognized in NHPs and in humans. These findings have important implications for the evaluation of new vaccines and diagnostics in the setting of non-human primate model of TB.

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Johnston, Jodie M., Vickery L. Arcus, Craig J. Morton, Michael W. Parker, and Edward N. Baker. "Crystal Structure of a Putative Methyltransferase from Mycobacterium tuberculosis: Misannotation of a Genome Clarified by Protein Structural Analysis." Journal of Bacteriology 185, no. 14 (July 15, 2003): 4057–65. http://dx.doi.org/10.1128/jb.185.14.4057-4065.2003.

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ABSTRACT Bioinformatic analyses of whole genome sequences highlight the problem of identifying the biochemical and cellular functions of many gene products that are at present uncharacterized. The open reading frame Rv3853 from Mycobacterium tuberculosis has been annotated as menG and assumed to encode an S-adenosylmethionine (SAM)-dependent methyltransferase that catalyzes the final step in menaquinone biosynthesis. The Rv3853 gene product has been expressed, refolded, purified, and crystallized in the context of a structural genomics program. Its crystal structure has been determined by isomorphous replacement and refined at 1.9 Å resolution to an R factor of 19.0% and R free of 22.0%. The structure strongly suggests that this protein is not a SAM-dependent methyltransferase and that the gene has been misannotated in this and other genomes that contain homologs. The protein forms a tightly associated, disk-like trimer. The monomer fold is unlike that of any known SAM-dependent methyltransferase, most closely resembling the phosphohistidine domains of several phosphotransfer systems. Attempts to bind cofactor and substrate molecules have been unsuccessful, but two adventitiously bound small-molecule ligands, modeled as tartrate and glyoxalate, are present on each monomer. These may point to biologically relevant binding sites but do not suggest a function. In silico screening indicates a range of ligands that could occupy these and other sites. The nature of these ligands, coupled with the location of binding sites on the trimer, suggests that proteins of the Rv3853 family, which are distributed throughout microbial and plant species, may be part of a larger assembly binding to nucleic acids or proteins.

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Brodin, Priscille, Karin Eiglmeier, Magali Marmiesse, Alain Billault, Thierry Garnier, Stefan Niemann, Stewart T. Cole, and Roland Brosch. "Bacterial Artificial Chromosome-Based Comparative Genomic Analysis Identifies Mycobacterium microti as a Natural ESAT-6 Deletion Mutant." Infection and Immunity 70, no. 10 (October 2002): 5568–78. http://dx.doi.org/10.1128/iai.70.10.5568-5578.2002.

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ABSTRACT Mycobacterium microti is a member of the Mycobacterium tuberculosis complex that causes tuberculosis in voles. Most strains of M. microti are harmless for humans, and some have been successfully used as live tuberculosis vaccines. In an attempt to identify putative virulence factors of the tubercle bacilli, genes that are absent from the avirulent M. microti but present in human pathogen M. tuberculosis or Mycobacterium bovis were searched for. A minimal set of 50 bacterial artificial chromosome (BAC) clones that covers almost all of the genome of M. microti OV254 was constructed, and individual BACs were compared to the corresponding BACs from M. bovis AF2122/97 and M. tuberculosis H37Rv. Comparison of pulsed-field gel-separated DNA digests of BAC clones led to the identification of 10 regions of difference (RD) between M. microti OV254 and M. tuberculosis. A 14-kb chromosomal region (RD1mic) that partly overlaps the RD1 deletion in the BCG vaccine strain was missing from the genomes of all nine tested M. microti strains. This region covers 13 genes, Rv3864 to Rv3876, in M. tuberculosis, including those encoding the potent ESAT-6 and CFP-10 antigens. In contrast, RD5mic, a region that contains three phospholipase C genes (plcA to -C), was missing from only the vole isolates and was present in M. microti strains isolated from humans. Apart from RD1mic and RD5mic other M. microti-specific deleted regions have been identified (MiD1 to MiD3). Deletion of MiD1 has removed parts of the direct repeat region in M. microti and thus contributes to the characteristic spoligotype of M. microti strains.

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Okkels, Limei Meng, Inger Brock, Frank Follmann, Else Marie Agger, Sandra M. Arend, Tom H. M. Ottenhoff, Fredrik Oftung, Ida Rosenkrands, and Peter Andersen. "PPE Protein (Rv3873) from DNA Segment RD1 of Mycobacterium tuberculosis: Strong Recognition of Both Specific T-Cell Epitopes and Epitopes Conserved within the PPE Family." Infection and Immunity 71, no. 11 (November 2003): 6116–23. http://dx.doi.org/10.1128/iai.71.11.6116-6123.2003.

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ABSTRACT Proteins encoded by DNA segment RD1 of Mycobacterium tuberculosis have recently been demonstrated to play important roles in bacterial virulence, vaccine development, and diagnostic reagent design. Previously, we characterized two immunodominant T-cell antigens, the early secreted antigen target (ESAT-6) and the 10-kDa culture filtrate protein (CFP10), which are encoded by the esx-lhp operon in this region. In the present study we characterized a third putative open reading frame in this region, rv3873, which encodes a PPE protein. We found that the rv3873 gene is expressed in M. tuberculosis H37Rv and that the native protein, Rv3873, is predominantly associated with the mycobacterial cell or wall. When tested as a His-tagged recombinant protein, Rv3873 stimulated high levels of gamma interferon secretion in peripheral blood mononuclear cells isolated from tuberculosis (TB) patients, as well as from healthy tuberculin purified protein derivative-positive donors. In contrast to other RD1-encoded antigens, Rv3873 was also found to be recognized by a significant proportion of Mycobacterium bovis BCG-vaccinated donors. Epitope mapping performed with overlapping peptides revealed a broad pattern of T-cell recognition comprising both TB-specific epitopes and epitopes also recognized by BCG-vaccinated donors. The immunodominant epitope (residues 118 to 135) for both TB patients and BCG-vaccinated individuals was found to be highly conserved among a large number of PPE family members.

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Mostowy, Serge, Debby Cousins, and Marcel A. Behr. "Genomic Interrogation of the Dassie Bacillus Reveals It as a Unique RD1 Mutant within the Mycobacterium tuberculosis Complex." Journal of Bacteriology 186, no. 1 (January 1, 2004): 104–9. http://dx.doi.org/10.1128/jb.186.1.104-109.2003.

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ABSTRACT Despite their remarkable genetic homology, members of the Mycobacterium tuberculosis complex express very different phenotypes, most notably in their spectra of clinical presentation. For example, M. tuberculosis is regarded as pathogenic to humans, whereas members having deleted RD1, such as Mycobacterium microti and Mycobacterium bovis BCG, are not. The dassie bacillus, an infrequent variant of the M. tuberculosis complex characterized as being most similar to M. microti, is the causative agent of tuberculosis (TB) in the dassie (Procavia capensis). Intriguingly, the dassie bacillus is not pathogenic to rabbits or guinea pigs and has never been documented to infect humans. Although it was identified more than a half-century ago, the reasons behind its attenuation are unknown. Because large sequence polymorphisms have presented themselves as the most obvious genomic distinction among members of the M. tuberculosis complex, the DNA content of the dassie bacillus was interrogated by Affymetrix GeneChip to identify regions that are absent from it but present in M. tuberculosis H37Rv. Comparison has led to the identification of nine regions of difference (RD), five of which are shared with M. microti (RDs 3, 7, 8, 9, and 10). Although the dassie bacillus does not share the other documented deletions in M. microti (RD1mic, RD5mic, MID1, MID2, and MID3), it has endured unique deletions in the regions of RD1, RD5, N-RD25, and Rv3081-Rv3082c (virS). RD1das, affecting only Rv3874-Rv3877, is the smallest natural deletion of the RD1 region uncovered and points to genes within this region that are likely implicated in virulence. Newfound deletions from the dassie bacillus are discussed in relation to their evolutionary and biological significance.

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Mikušová, Katarína, Martina Beláňová, Jana Korduláková, Kristine Honda, Michael R. McNeil, Sebabrata Mahapatra, Dean C. Crick, and Patrick J. Brennan. "Identification of a Novel Galactosyl Transferase Involved in Biosynthesis of the Mycobacterial Cell Wall." Journal of Bacteriology 188, no. 18 (September 15, 2006): 6592–98. http://dx.doi.org/10.1128/jb.00489-06.

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ABSTRACT The possibility of the Rv3782 protein of Mycobacterium tuberculosis being a putative galactosyl transferase (GalTr) implicated in galactan synthesis arose from its similarity to the known GalTr Rv3808c, its classification as a nucleotide sugar-requiring inverting glycosyltransferase (GT-2 family), and its location within the “possible arabinogalactan biosynthetic gene cluster” of M. tuberculosis. In order to study the function of the enzyme, active membrane and cell wall fractions from Mycobacterium smegmatis containing the overexpressed Rv3782 protein were incubated with endogenous decaprenyldiphosphoryl-N-acetylglucosaminyl-rhamnose (C50-P-P-GlcNAc-Rha) as the primary substrate for galactan synthesis and UDP-[14C]galactopyranose as the immediate precursor of UDP-[14C]galactofuranose, the ultimate source of all of the galactofuranose (Galf) units of galactan. Obvious increased and selective synthesis of C50-P-P-GlcNAc-Rha-Galf-Galf, the earliest product in the pathway leading to the fully polymerized galactan, was observed, suggesting that Rv3782 encodes a GalTr involved in the first stages of galactan synthesis. Time course experiments pointed to a possible bifunctional enzyme responsible for the initial synthesis of C50-P-P-GlcNAc-Rha-Galf, followed by immediate conversion to C50-P-P-GlcNAc-Rha-Galf-Galf. Thus, Rv3782 appears to be the initiator of galactan synthesis, while Rv3808c continues with the subsequent polymerization events.

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Wang, Sen, Jiazhen Chen, Ying Zhang, Ni Diao, Shu Zhang, Jing Wu, Chanyi Lu, et al. "Mycobacterium tuberculosis Region of Difference (RD) 2 Antigen Rv1985c and RD11 Antigen Rv3425 Have the Promising Potential To Distinguish Patients with Active Tuberculosis from M. bovis BCG-Vaccinated Individuals." Clinical and Vaccine Immunology 20, no. 1 (November 7, 2012): 69–76. http://dx.doi.org/10.1128/cvi.00481-12.

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ABSTRACTAntigens encoded in the region of difference (RD) ofMycobacterium tuberculosisconstitute a potential source of specific immunodiagnostic antigens for distinguishing tuberculosis (TB) infection from BCG vaccination. We evaluated the diagnostic potential of specific T-cell epitopes selected from two immunodominant antigens, Rv1985c and Rv3425, from RD2 and RD11, respectively, on the basis of epitope mapping, in TB patients and BCG-vaccinated healthy individuals. Using a whole-blood gamma interferon release assay, a wide array of epitopes was recognized on both Rv1985c and Rv3425 in TB patients. Those epitopes that could specifically discriminate TB infection from BCG vaccination were carefully selected, and the most promising peptide pools from Rv1985c showed a sensitivity of 53.9% and a specificity of 95.5%. When the novel specific peptides from Rv1985c joined the diagnostic antigens in the QuantiFERON-TB Gold In-Tube (QFT-IT) assay, the sensitivity was increased from 86.4% to 96.2%, with no drop in specificity. These results indicate that the peptide pools selected from Rv1985c and Rv3425 have the potential to diagnose TB infection by a method that may be routinely used in clinical laboratories.

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Yang, Min, Chun-Hui Gao, Jialing Hu, Chao Dong, and Zheng-Guo He. "Characterization of the interaction between a SirR family transcriptional factor ofMycobacterium tuberculosis, encoded by Rv2788, and a pair of toxin-antitoxin proteins RelJ/K, encoded by Rv3357 and Rv3358." FEBS Journal 281, no. 12 (May 12, 2014): 2726–37. http://dx.doi.org/10.1111/febs.12815.

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Shi, Libin, Roukun Zhou, Zhentong Liu, Todd L. Lowary, Peter H. Seeberger, Bridget L. Stocker, Dean C. Crick, Kay-Hooi Khoo, and Delphi Chatterjee. "Transfer of the First Arabinofuranose Residue to Galactan Is Essential for Mycobacterium smegmatis Viability." Journal of Bacteriology 190, no. 15 (June 13, 2008): 5248–55. http://dx.doi.org/10.1128/jb.00028-08.

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ABSTRACT The mycobacterial arabinan is an elaborate component of the cell wall with multiple glycosyl linkages and no repeating units. In Mycobacterium spp., the Emb proteins (EmbA, EmbB, and EmbC) have been identified as putative mycobacterial arabinosyltransferases implicated in the biogenesis of the cell wall arabinan. Furthermore, it is now evident that the EmbA and EmbB proteins are involved in the assembly of the nonreducing terminal motif of arabinogalactan and EmbC is involved in transferring arabinose, perhaps in the early stage of arabinan synthesis in lipoarabinomannan. It has also been shown that the Emb proteins are a target of the antimycobacterial drug ethambutol (EMB). In the search for additional mycobacterial arabinosyltransferases in addition to the Emb proteins, we disrupted MSMEG_6386 (an orthologue of Rv3792 and a gene upstream of embC) in Mycobacterium smegmatis. Allelic exchange at the chromosomal MSMEG_6386 locus of M. smegmatis could only be achieved in the presence of a rescue plasmid carrying a functional copy of MSMEG_6386 or Rv3792, strongly suggesting that MSMEG_6386 is essential. An in vitro arabinosyltransferase assay using a membrane preparation from M. smegmatis expressing Rv3792 and synthetic β-d-Galf-(1→5)-β-d-Galf-(1→6)-β-d-Galf-octyl and β-d-Galf-(1→6)-β-d-Galf-(1→5)-β-d-Galf-octyl showed that Rv3792 gene product can transfer an arabinose residue to the C-5 position of the internal 6-linked galactose. The reactions were insensitive to EMB, and when α-d-Manp-(1→6)-α-d-Manp-(1→6)-α-d-Manp-octylthiomethyl was used as an acceptor, no product was formed. These observations indicate that transfer of the first arabinofuranose residue to galactan is essential for M. smegmatis viability.

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Lagutkin, Denis, Anna Panova, Anatoly Vinokurov, Alexandra Gracheva, Anastasia Samoilova, and Irina Vasilyeva. "Genome-Wide Study of Drug Resistant Mycobacterium tuberculosis and Its Intra-Host Evolution during Treatment." Microorganisms 10, no. 7 (July 17, 2022): 1440. http://dx.doi.org/10.3390/microorganisms10071440.

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The emergence of drug resistant Mycobacterium tuberculosis (MTB) strains has become a global public health problem, while, at the same time, there has been development of new antimicrobial agents. The main goals of this study were to determine new variants associated with drug resistance in MTB and to observe which polymorphisms emerge in MTB genomes after anti-tuberculosis treatment. We performed whole-genome sequencing of 152 MTB isolates including 70 isolates as 32 series of pre- and post-treatment MTB. Based on genotypes and phenotypic drug susceptibility, we conducted phylogenetic convergence-based genome-wide association study (GWAS) with streptomycin-, isoniazid-, rifampicin-, ethambutol-, fluoroquinolones-, and aminoglycosides-resistant MTB against susceptible ones. GWAS revealed statistically significant associations of SNPs within Rv2820c, cyp123 and indels in Rv1269c, Rv1907c, Rv1883c, Rv2407, Rv3785 genes with resistant MTB phenotypes. Comparisons of serial isolates showed that treatment induced different patterns of intra-host evolution. We found indels within Rv1435c and ppsA that were not lineage-specific. In addition, Beijing-specific polymorphisms within Rv0036c, Rv0678, Rv3433c, and dop genes were detected in post-treatment isolates. The appearance of Rv3785 frameshift insertion in 2 post-treatment strains compared to pre-treatment was also observed. We propose that the insertion within Rv3785, which was a GWAS hit, might affect cell wall biosynthesis and probably mediates a compensatory mechanism in response to treatment. These results may shed light on the mechanisms of MTB adaptation to chemotherapy and drug resistance formation.

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Hinks, Timothy S. C., Davinder P. S. Dosanjh, John A. Innes, Geoffrey Pasvol, Sarah Hackforth, Hansa Varia, Kerry A. Millington, et al. "Frequencies of Region of Difference 1 Antigen-Specific but Not Purified Protein Derivative-Specific Gamma Interferon-Secreting T Cells Correlate with the Presence of Tuberculosis Disease but Do Not Distinguish Recent from Remote Latent Infections." Infection and Immunity 77, no. 12 (September 14, 2009): 5486–95. http://dx.doi.org/10.1128/iai.01436-08.

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ABSTRACT The majority of individuals infected with Mycobacterium tuberculosis achieve lifelong immune containment of the bacillus. What constitutes this effective host immune response is poorly understood. We compared the frequencies of gamma interferon (IFN-γ)-secreting T cells specific for five region of difference 1 (RD1)-encoded antigens and one DosR-encoded antigen in 205 individuals either with active disease (n = 167), whose immune responses had failed to contain the bacillus, or with remotely acquired latent infection (n = 38), who had successfully achieved immune control, and a further 149 individuals with recently acquired asymptomatic infection. When subjects with an IFN-γ enzyme-linked immunospot (ELISpot) assay response to one or more RD1-encoded antigens were analyzed, T cells from subjects with active disease recognized more pools of peptides from these antigens than T cells from subjects with nonrecent latent infection (P = 0.002). The T-cell frequencies for peptide pools were greater for subjects with active infection than for subjects with nonrecent latent infection for summed RD1 peptide pools (P ≤ 0.006) and culture filtrate protein 10 (CFP-10) antigen (P = 0.029). Individuals with recently acquired (<6 months) versus remotely acquired (>6 months) latent infection did not differ in numbers of peptide pools recognized, proportions recognizing any individual antigen or peptide pool, or antigen-specific T-cell frequencies (P ≥ 0.11). The hierarchy of immunodominance for different antigens was purified protein derivative (PPD) > CFP-10 > early secretory antigenic target 6 > Rv3879c > Rv3878 > Rv3873 > Acr1, and the hierarchies were very similar for active and remotely acquired latent infections. Responses to the DosR antigen α-crystallin were not associated with latency (P = 0.373). In contrast to the RD1-specific responses, the responses to PPD were not associated with clinical status (P > 0.17) but were strongly associated with positive tuberculin skin test results (≥15-mm induration; P ≤ 0.01). Our results suggest that RD1-specific IFN-γ-secreting T-cell frequencies correlate with the presence of disease rather than with protective immunity in M. tuberculosis-infected individuals and do not distinguish recently acquired asymptomatic infection from remotely acquired latent infection.

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Chandra, Govind, Keith F. Chater, and Stephen Bornemann. "Unexpected and widespread connections between bacterial glycogen and trehalose metabolism." Microbiology 157, no. 6 (June 1, 2011): 1565–72. http://dx.doi.org/10.1099/mic.0.044263-0.

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Glycogen, a large α-glucan, is a ubiquitous energy storage molecule among bacteria, and its biosynthesis by the classical GlgC-GlgA pathway and its degradation have long been well understood – or so we thought. A second pathway of α-glucan synthesis, the four-step GlgE pathway, was recently discovered in mycobacteria. It requires trehalose as a precursor, and has been genetically validated as a novel anti-tuberculosis drug target. The ability to convert glycogen into trehalose was already known, so the GlgE pathway provides a complementary way of cycling these two metabolites. As well as containing cytosolic storage glycogen, mycobacteria possess an outer capsule containing a glycogen-like α-glucan that is implicated in immune system evasion, so the GlgE pathway might be linked to capsular α-glucan biosynthesis. Another pathway (the Rv3032 pathway) for α-glucan biosynthesis in mycobacteria generates a methylglucose lipopolysaccharide thought to be associated with fatty acid metabolism. A comparative genomic analysis was carried out to evaluate the occurrence and role of the classical pathway, the new GlgE pathway and the Rv3032 pathway across bacteria occupying very different ecological niches. The GlgE pathway is represented in 14 % of sequenced genomes from diverse bacteria (about half as common as the classical pathway), while the Rv3032 pathway is restricted with few exceptions to mycobacteria, and the GlgB branching enzyme, usually presumed to be associated with the classical pathway, correlates more strongly with the new GlgE pathway. The microbiological implications of recent discoveries in the light of the comparative genomic analysis are discussed.

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Meena, Laxman S., and Jaishree Meena. "Cloning and characterization of a novel PE_PGRS60 protein (Rv3652) ofMycobacterium tuberculosisH37Rv exhibit fibronectin-binding property." Biotechnology and Applied Biochemistry 63, no. 4 (July 30, 2015): 525–31. http://dx.doi.org/10.1002/bab.1411.

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Teixeira, Henrique Couto, Ana Márcia Menezes Mattos, Caroline Souza Almeida, Lily Paola Martinez Abad, Kees Franken, and Tom H. M. Ottenhoff. "IgG1 and Th1 responses to DosR, Rpf and active growth phase antigens of Mycobacterium tuberculosis in Brazilian tuberculosis patients." Journal of Immunology 196, no. 1_Supplement (May 1, 2016): 65.15. http://dx.doi.org/10.4049/jimmunol.196.supp.65.15.

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Abstract Tuberculosis (TB) is serious problem worldwide. New antigens from Mycobacterium tuberculosis are being investigated in order to improve the diagnosis of latent TB infection and TB disease. In this study, serum levels of IgG1 antibodies against active growth phase antigens (ESAT-6/CFP-10, Rv0717 and Rv3353), dormancy-related (DosR) antigens (Rv1733, Rv1737, Rv2029 and Rv2628), and resuscitation promoting factors (Rpfs Rv0867 and Rv2389) were evaluated in patients with TB before and after chemotherapy using ELISA. Antigen-induced IFN-γ, TNF-α, IL-17, IL-10 and IL-4 were evaluated in supernatants of PBMC cultures. Our results indicate that patients with pulmonary TB express high levels of IgG1 antibodies against ESAT-6/CFP-10, Rv0717, Rv3353, Rv1733, Rv2029 and Rv2628 Rv0867 in the active phase of the disease in comparison to healthy controls (p<0.001). These levels declined to control levels after the completion of six months treatment. ROC analysis confirmed the good performance of Rv0717, Rv1733, Rv3353, Rv0867, Rv2029 and Rv2628 antigens. Interestingly, Rv0717 and Rv1733 antigens induced an IgG1 peak response after 1–3 months of chemotherapy (P<0.01). Similarly, IFN-γ and TNF-α peaked early during treatment in response to ESAT-6/CFP-10, Rv1733 and Rv2029, and declined to control levels after 6 months of chemotherapy. The study groups did not differ in respect to IL-17, IL-10 and IL-4. Taken together, these data further reinforce a possible correlation of IgG1 production with Th1 responses in TB. Moreover, detecting IgG1 antibodies against M. tuberculosis antigens, including DosR and Rpf proteins, may represent an additional tool in the diagnosis of tuberculosis. Financial support: FAPEMIG, CNPq and CAPES, EU and NWO-TOP.

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Abendroth, Jan, Andrew Frando, Isabelle Q. Phan, Bart L. Staker, Peter J. Myler, Thomas E. Edwards, and Christoph Grundner. "Mycobacterium tuberculosis Rv3651 is a triple sensor-domain protein." Protein Science 27, no. 2 (December 5, 2017): 568–72. http://dx.doi.org/10.1002/pro.3343.

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Mukherjee, P., M. Dutta, P. Datta, A. Dasgupta, R. Pradhan, M. Pradhan, M. Kundu, J. Basu, and P. Chakrabarti. "The RD1-encoded antigen Rv3872 of Mycobacterium tuberculosis as a potential candidate for serodiagnosis of tuberculosis." Clinical Microbiology and Infection 13, no. 2 (February 2007): 146–52. http://dx.doi.org/10.1111/j.1469-0691.2006.01660.x.

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Sánchez-Barinas, Christian David, Marisol Ocampo, Luisa Tabares, Maritza Bermúdez, Manuel Alfonso Patarroyo, and Manuel Elkin Patarroyo. "Specific Binding Peptides from Rv3632: A Strategy for BlockingMycobacterium tuberculosisEntry to Target Cells?" BioMed Research International 2019 (April 14, 2019): 1–13. http://dx.doi.org/10.1155/2019/8680935.

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Tuberculosis is an infectious disease caused byMycobacterium tuberculosis(Mtb, i.e., the aetiological agent); the WHO has established this disease as high priority due to its ensuing mortality.Mtbuses a range of mechanisms for preventing its elimination by an infected host; new, viable alternatives for blocking the host-pathogen interaction are thus sought constantly. This article updates our laboratory’s systematic search for antigens using bioinformatics tools to clarify theMtbH37Rv Rv3632 protein’s topology and location. This article reports a C-terminal region consisting of peptides 39255 and 39256 (81Thr-Arg114) having high specific binding regarding two infection-related cell lines (A549 and U937); they inhibited mycobacterial entry to U937 cells in a concentration-dependent manner. Rv3632 forms part of the mycobacterial cell envelope, formed by six linear synthetic peptides. Circular dichroism enabled determining the protein’s secondary structure. It was also found that peptide 39254 (61Gly-Thr83) was a HABP for alveolar epithelial cells and inhibited mycobacteria entry to these cells regardless of concentration. Sera from active or latent tuberculosis patients did not recognise HABPs 39254 and 39256. These sequences represent a promising approach aiming at their ongoing modification and for including them when designing a multi-epitope, anti-tuberculosis vaccine.

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Williams, LaTonya D., Xiaoying Shen, Sheetal S. Sawant, Siriwat Akapirat, Lindsay C. Dahora, Matthew Zirui Tay, Sherry Stanfield-Oakley, et al. "Viral vector delivered immunogen focuses HIV-1 antibody specificity and increases durability of the circulating antibody recall response." PLOS Pathogens 19, no. 5 (May 31, 2023): e1011359. http://dx.doi.org/10.1371/journal.ppat.1011359.

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The modestly efficacious HIV-1 vaccine regimen (RV144) conferred 31% vaccine efficacy at 3 years following the four-shot immunization series, coupled with rapid waning of putative immune correlates of decreased infection risk. New strategies to increase magnitude and durability of protective immunity are critically needed. The RV305 HIV-1 clinical trial evaluated the immunological impact of a follow-up boost of HIV-1-uninfected RV144 recipients after 6–8 years with RV144 immunogens (ALVAC-HIV alone, AIDSVAX B/E gp120 alone, or ALVAC-HIV + AIDSVAX B/E gp120). Previous reports demonstrated that this regimen elicited higher binding, antibody Fc function, and cellular responses than the primary RV144 regimen. However, the impact of the canarypox viral vector in driving antibody specificity, breadth, durability and function is unknown. We performed a follow-up analysis of humoral responses elicited in RV305 to determine the impact of the different booster immunogens on HIV-1 epitope specificity, antibody subclass, isotype, and Fc effector functions. Importantly, we observed that the ALVAC vaccine component directly contributed to improved breadth, function, and durability of vaccine-elicited antibody responses. Extended boosts in RV305 increased circulating antibody concentration and coverage of heterologous HIV-1 strains by V1V2-specific antibodies above estimated protective levels observed in RV144. Antibody Fc effector functions, specifically antibody-dependent cellular cytotoxicity and phagocytosis, were boosted to higher levels than was achieved in RV144. V1V2 Env IgG3, a correlate of lower HIV-1 risk, was not increased; plasma Env IgA (specifically IgA1), a correlate of increased HIV-1 risk, was elevated. The quality of the circulating polyclonal antibody response changed with each booster immunization. Remarkably, the ALVAC-HIV booster immunogen induced antibody responses post-second boost, indicating that the viral vector immunogen can be utilized to selectively enhance immune correlates of decreased HIV-1 risk. These results reveal a complex dynamic of HIV-1 immunity post-vaccination that may require careful balancing to achieve protective immunity in the vaccinated population. Trial registration: RV305 clinical trial (ClinicalTrials.gov number, NCT01435135). ClinicalTrials.gov Identifier: NCT00223080, ClinicalTrials.gov Identifier: NCT01931358, ClinicalTrials.gov Identifier: NCT01923610, ClinicalTrials.gov Identifier: NCT01461447.

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Jiang, Yi, Li Wan, Zhijian Zhang, Haican Liu, Hui Pang, Wen Zhang, Xiuqin Zhao, et al. "Conserved alanine rich protein Rv3878 in Mycobacterium tuberculosis contains sequence polymorphisms." Tuberculosis 94, no. 3 (May 2014): 245–51. http://dx.doi.org/10.1016/j.tube.2014.02.002.

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Saravanan, Parameswaran, Hindupur Avinash, Vikash Kumar Dubey, and Sanjukta Patra. "Targeting essential cell wall lipase Rv3802c for potential therapeutics against tuberculosis." Journal of Molecular Graphics and Modelling 38 (September 2012): 235–42. http://dx.doi.org/10.1016/j.jmgm.2012.06.016.

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Kana, Bavesh D., Garth L. Abrahams, Nackmoon Sung, Digby F. Warner, Bhavna G. Gordhan, Edith E. Machowski, Liana Tsenova, et al. "Role of the DinB Homologs Rv1537 and Rv3056 in Mycobacterium tuberculosis." Journal of Bacteriology 192, no. 8 (February 5, 2010): 2220–27. http://dx.doi.org/10.1128/jb.01135-09.

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ABSTRACT The environment encountered by Mycobacterium tuberculosis during infection is genotoxic. Most bacteria tolerate DNA damage by engaging specialized DNA polymerases that catalyze translesion synthesis (TLS) across sites of damage. M. tuberculosis possesses two putative members of the DinB class of Y-family DNA polymerases, DinB1 (Rv1537) and DinB2 (Rv3056); however, their role in damage tolerance, mutagenesis, and survival is unknown. Here, both dinB1 and dinB2 are shown to be expressed in vitro in a growth phase-dependent manner, with dinB2 levels 12- to 40-fold higher than those of dinB1. Yeast two-hybrid analyses revealed that DinB1, but not DinB2, interacts with the β-clamp, consistent with its canonical C-terminal β-binding motif. However, knockout of dinB1, dinB2, or both had no effect on the susceptibility of M. tuberculosis to compounds that form N 2-dG adducts and alkylating agents. Similarly, deletion of these genes individually or in combination did not affect the rate of spontaneous mutation to rifampin resistance or the spectrum of resistance-conferring rpoB mutations and had no impact on growth or survival in human or mouse macrophages or in mice. Moreover, neither gene conferred a mutator phenotype when expressed ectopically in Mycobacterium smegmatis. The lack of the effect of altering the complements or expression levels of dinB1 and/or dinB2 under conditions predicted to be phenotypically revealing suggests that the DinB homologs from M. tuberculosis do not behave like their counterparts from other organisms.

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Okkels, Limei Meng, and Peter Andersen. "Protein-Protein Interactions of Proteins from the ESAT-6 Family of Mycobacterium tuberculosis." Journal of Bacteriology 186, no. 8 (April 15, 2004): 2487–91. http://dx.doi.org/10.1128/jb.186.8.2487-2491.2004.

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ABSTRACT In the present study, we demonstrate that, in analogy with the genes encoding ESAT-6 and CFP-10, the genes rv0287 and rv0288 from the ESAT-6 gene family are cotranscribed. Using Western-Western blotting and protein-print overlay methodologies, we demonstrate that ESAT-6 and CFP-10, as well as the protein pair Rv0288/Rv0287, interact pairwise in a highly specific way. Most notably, the ESAT-6 proteins interact directly with Rv3873, a possible cell envelope component of the ESAT-6 secretion pathway.

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Eoh, Hyungjin, Amanda C. Brown, Lori Buetow, William N. Hunter, Tanya Parish, Devinder Kaur, Patrick J. Brennan, and Dean C. Crick. "Characterization of the Mycobacterium tuberculosis 4-Diphosphocytidyl-2-C-Methyl-d-Erythritol Synthase: Potential for Drug Development." Journal of Bacteriology 189, no. 24 (October 5, 2007): 8922–27. http://dx.doi.org/10.1128/jb.00925-07.

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ABSTRACT Mycobacterium tuberculosis utilizes the methylerythritol phosphate (MEP) pathway for biosynthesis of isopentenyl diphosphate and its isomer, dimethylallyl diphosphate, precursors of all isoprenoid compounds. This pathway is of interest as a source of new drug targets, as it is absent from humans and disruption of the responsible genes has shown a lethal phenotype for Escherichia coli. In the MEP pathway, 4-diphosphocytidyl-2-C-methyl-d-erythritol is formed from 2-C-methyl-d-erythritol 4-phosphate (MEP) and CTP in a reaction catalyzed by a 4-diphosphocytidyl-2-C-methyl-d-erythritol synthase (IspD). In the present work, we demonstrate that Rv3582c is essential for M. tuberculosis: Rv3582c has been cloned and expressed, and the encoded protein has been purified. The purified M. tuberculosis IspD protein was capable of catalyzing the formation of 4-diphosphocytidyl-2-C-methyl-d-erythritol in the presence of MEP and CTP. The enzyme was active over a broad pH range (pH 6.0 to 9.0), with peak activity at pH 8.0. The activity was absolutely dependent upon divalent cations, with 20 mM Mg2+ being optimal, and replacement of CTP with other nucleotide 5′-triphosphates did not support activity. Under the conditions tested, M. tuberculosis IspD had Km values of 58.5 μM for MEP and 53.2 μM for CTP. Calculated k cat and k cat/Km values were 0.72 min−1 and 12.3 mM−1 min−1 for MEP and 1.0 min−1 and 18.8 mM−1 min−1 for CTP, respectively.

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Vani, Janakiraman, Melukote S. Shaila, Jamma Trinath, Kithiganahalli N. Balaji, Srini V. Kaveri, and Jagadeesh Bayry. "Mycobacterium tuberculosis Cell Wall–Associated Rv3812 Protein Induces Strong Dendritic Cell–Mediated Interferon γ Responses and Exhibits Vaccine Potential." Journal of Infectious Diseases 208, no. 6 (June 20, 2013): 1034–36. http://dx.doi.org/10.1093/infdis/jit281.

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Colangeli, Roberto, John S. Spencer, Pablo Bifani, Alan Williams, Konstantin Lyashchenko, Marc A. Keen, Preston J. Hill, John Belisle, and Maria Laura Gennaro. "MTSA-10, the Product of the Rv3874 Gene of Mycobacterium tuberculosis, Elicits Tuberculosis-Specific, Delayed-Type Hypersensitivity in Guinea Pigs." Infection and Immunity 68, no. 2 (February 1, 2000): 990–93. http://dx.doi.org/10.1128/iai.68.2.990-993.2000.

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ABSTRACT In a search for new skin test reagents specific for tuberculosis, we found that the antigen encoded by gene Rv3874 of Mycobacterium tuberculosis elicited delayed-type hypersensitivity in M. tuberculosis-infected guinea pigs but not in control animals immunized with Mycobacterium bovis bacillus Calmette-Guérin (BCG) or Mycobacterium avium. The antigen, which was named MTSA-10 (for M. tuberculosis-specific antigen 10), is a prime candidate for a component of a new tuberculin that will allow discrimination by a skin test of latent M. tuberculosis infection from vaccination with BCG or from sensitization with environmental, nontuberculous mycobacteria.

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Beláňová, Martina, Petronela Dianišková, Patrick J. Brennan, Gladys C. Completo, Natisha L. Rose, Todd L. Lowary, and Katarína Mikušová. "Galactosyl Transferases in Mycobacterial Cell Wall Synthesis." Journal of Bacteriology 190, no. 3 (November 30, 2007): 1141–45. http://dx.doi.org/10.1128/jb.01326-07.

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ABSTRACT Two galactosyl transferases can apparently account for the full biosynthesis of the cell wall galactan of mycobacteria. Evidence is presented based on enzymatic incubations with purified natural and synthetic galactofuranose (Galf) acceptors that the recombinant galactofuranosyl transferase, GlfT1, from Mycobacterium smegmatis, the Mycobacterium tuberculosis Rv3782 ortholog known to be involved in the initial steps of galactan formation, harbors dual β-(1→4) and β-(1→5) Galf transferase activities and that the product of the enzyme, decaprenyl-P-P-GlcNAc-Rha-Galf-Galf, serves as a direct substrate for full polymerization catalyzed by another bifunctional Galf transferase, GlfT2, the Rv3808c enzyme.

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West, Nicholas P., Katie M. Cergol, Millie Xue, Elizabeth J. Randall, Warwick J. Britton, and Richard J. Payne. "Inhibitors of an essential mycobacterial cell wall lipase (Rv3802c) as tuberculosis drug leads." Chemical Communications 47, no. 18 (2011): 5166. http://dx.doi.org/10.1039/c0cc05635a.

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Saravanan, Parameswaran, and Sanjukta Patra. "Discovery of Potential Dual Inhibitors Against Lipases Rv0183 and Rv3802c for Tuberculosis Therapeutics." Letters in Drug Design & Discovery 13, no. 2 (November 12, 2015): 185–95. http://dx.doi.org/10.2174/1570180812999150812165215.

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Sharma, Divakar, Manju Lata, Mohammad Faheem, Asad Ullah Khan, Beenu Joshi, Krishnamurthy Venkatesan, Sangeeta Shukla, and Deepa Bisht. "M. tuberculosis ferritin (Rv3841): Potential involvement in Amikacin (AK) & Kanamycin (KM) resistance." Biochemical and Biophysical Research Communications 478, no. 2 (September 2016): 908–12. http://dx.doi.org/10.1016/j.bbrc.2016.08.049.

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Agger, Else Marie, Inger Brock, Limei Meng Okkels, Sandra M. Arend, Claus S. Aagaard, Karin N. Weldingh, and Peter Andersen. "Human T-cell responses to the RD1-encoded protein TB27.4 (Rv3878) from Mycobacterium tuberculosis." Immunology 110, no. 4 (December 2003): 507–12. http://dx.doi.org/10.1111/j.1365-2567.2003.01763.x.

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Parker, Sarah K., Robert M. Barkley, John G. Rino, and Michael L. Vasil. "Mycobacterium tuberculosis Rv3802c Encodes a Phospholipase/Thioesterase and Is Inhibited by the Antimycobacterial Agent Tetrahydrolipstatin." PLoS ONE 4, no. 1 (January 26, 2009): e4281. http://dx.doi.org/10.1371/journal.pone.0004281.

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Luthra, Amit, Anjum Mahmood, Ashish Arora, and Ravishankar Ramachandran. "Characterization of Rv3868, an Essential Hypothetical Protein of the ESX-1 Secretion System inMycobacterium tuberculosis." Journal of Biological Chemistry 283, no. 52 (October 30, 2008): 36532–41. http://dx.doi.org/10.1074/jbc.m807144200.

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Luthra, Amit, Amit Gaur, and Ravishankar Ramachandran. "Rv3868 (EccA1), an essential component of the Mycobacterium tuberculosis ESX-1 secretion system, is thermostable." Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics 1834, no. 6 (June 2013): 1181–86. http://dx.doi.org/10.1016/j.bbapap.2013.02.004.

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West, Nicholas P., Katie M. Cergol, Millie Xue, Elizabeth J. Randall, Warwick J. Britton, and Richard J. Payne. "ChemInform Abstract: Inhibitors of an Essential Mycobacterial Cell Wall Lipase (Rv3802c) as Tuberculosis Drug Leads." ChemInform 42, no. 36 (August 11, 2011): no. http://dx.doi.org/10.1002/chin.201136185.

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Cockle, P. J., S. V. Gordon, R. G. Hewinson, and H. M. Vordermeier. "Field Evaluation of a Novel Differential Diagnostic Reagent for Detection of Mycobacterium bovis in Cattle." Clinical and Vaccine Immunology 13, no. 10 (August 30, 2006): 1119–24. http://dx.doi.org/10.1128/cvi.00209-06.

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Abstract:

ABSTRACT In the search for improved tools with which to control bovine tuberculosis, the development of enhanced immunodiagnostic reagents is a high priority. Such reagents are required to improve the performance of tuberculin-based reagents and allow the discrimination of vaccinated cattle from those infected with Mycobacterium bovis. In this study, we identified the immunodominant, frequently recognized peptides from Rv3873, Rv3879c, Rv0288, and Rv3019c, which, together with peptides comprising the current lead diagnostic antigens, ESAT-6 and CFP-10, were formulated into a peptide cocktail. In a test of naturally infected cattle, this cocktail was significantly better than tuberculin was for identifying skin test-negative animals with confirmed bovine tuberculosis. In addition, the specificity of this cocktail was not compromised by Mycobacterium bovis BCG vaccination. In summary, our results prioritize this peptide-based, fully synthetic reagent for assessment in larger trials.

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Wang, Jiuling, Yaqing Qie, Wei Liu, and Honghai Wang. "Protective efficacy of a recombinant BCG secreting antigen 85B/Rv3425 fusion protein againstMycobacterium tuberculosisinfection in mice." Human Vaccines & Immunotherapeutics 8, no. 12 (December 2012): 1869–74. http://dx.doi.org/10.4161/hv.21817.

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Ramulu, Hemalatha G., Adindla Swathi, and Lalitha Guruprasad. "The Rv3799-Rv3807 Gene Cluster inMycobacterium TuberculosisGenome Corresponds to the ‘Ancient Conserved Region’ in CMN Mycolyltransferases." Evolutionary Bioinformatics 2 (January 2006): 117693430600200. http://dx.doi.org/10.1177/117693430600200015.

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Journal articles on the topic 'Rv3852'

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