Mycobacterium tuberculosis Glycoproteomics Based on ConA-Lectin Affinity Capture of Mannosylated Proteins

Departamento de Inmunologia, Instituto de Investigaciones Biomedicas, Universidad Nacional Autonoma de Mexico, Mexico.
Journal of Proteome Research (Impact Factor: 4.25). 03/2009; 8(2):721-33. DOI: 10.1021/pr800756a
Source: PubMed


A Mycobacterium tuberculosis culture filtrate enriched with mannose-containing proteins was resolved by 2-DE gel. After ConA ligand blotting, 41 proteins were identified by mass spectrometry as putative glycoproteins with 34 of them new probably mannosylated proteins. These results contribute to the construction of the ConA affinity glycoprotein database of M. tuberculosis, and provide useful information for understanding the biological role of glycoproteins in mycobacteria.

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Available from: Antonio J. Vallecillo, Jun 22, 2015

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Article: Mycobacterium tuberculosis Glycoproteomics Based on ConA-Lectin Affinity Capture of Mannosylated Proteins

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    • "LprG is an antigenic lipoprotein with a potential role in bacterial cell wall assembly. This protein was previously described as P27 in the Mycobacterium tuberculosis complex [2] [3] [4] [5] and the lprG gene has been annotated as Rv1411c in the "
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    ABSTRACT: The lprG-p55 operon of Mycobacterium tuberculosis and Mycobacterium bovis is involved in the transport of toxic compounds. P55 is an efflux pump that provides resistance to several drugs, while LprG is a lipoprotein that modulates the host's immune response against mycobacteria. The knockout mutation of this operon severely reduces the replication of both mycobacterial species during infection in mice and increases susceptibility to toxic compounds. In order to gain insight into the function of LprG in the Mycobacterium avium complex, in this study, we assayed the effect of the deletion of lprG gene in the D4ER strain of Mycobacterium avium subsp. avium. The replacement of lprG gene with a hygromycin cassette caused a polar effect on the expression of p55. Also, a twofold decrease in ethidium bromide susceptibility was observed and the resistance to the antibiotics rifampicin, amikacin, linezolid, and rifabutin was impaired in the mutant strain. In addition, the mutation decreased the virulence of the bacteria in macrophages in vitro and in a mice model in vivo. These findings clearly indicate that functional LprG and P55 are necessary for the correct transport of toxic compounds and for the survival of MAA in vitro and in vivo.
    BioMed Research International 05/2014; 2014:809585. DOI:10.1155/2014/809585 · 2.71 Impact Factor
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    • "The cloning, expression and purification of the M. tuberculosis Rv1411c (p27) protein was performed as previously described [45]. The full length of Rv1818c (PE_PGRS33) gene cloned into PET15b fused to a histidine tag was a kind gift from Dr. M.J. Brennan (CBER, FDA, Bethesda, MD, USA). "
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    12/2012; 2(1):9. DOI:10.1186/2042-5783-2-9
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    • "Functional data on the involvement of mycobacterial lipoproteins in ABC transporters (PhoS123), two component regulatory systems (LpqB and LprF) [7], [8], biosynthetic pathways of cell wall components (LpqW, LppX) [9], [10], resuscitation of dormant cells (RpfB) [11], cytokine responses and regulation of antigen presentation by host cells as Toll like-receptor ligands (LprA, LprG, LpqH) have been reported [12], [13]. Although very few of them have been extensively characterized biochemically, it is striking to note that most lipoproteins studied so far are also glycosylated [14] as it was shown for PstS, a lipoprotein in the related actinomycete Streptomyces coelicolor [15] This original feature has been very clearly shown for LpqH [16], LprF [17], SodC [18] and PhoS1 [19]. The role of lipoprotein glycosylation is not yet clear, but could be a common post-translational modification that would act as a signal for protein export to the cell wall or the extracellular medium. "
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    PLoS ONE 09/2012; 7(9):e46225. DOI:10.1371/journal.pone.0046225 · 3.23 Impact Factor
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