Protein O-mannosylation deficiency increases LprG-associated lipoarabinomannan release by Mycobacterium tuberculosis and enhances the TLR2-associated inflammatory response.
Sci Rep
; 7(1): 7913, 2017 08 11.
Article
em En
| MEDLINE
| ID: mdl-28801649
ABSTRACT
Protein O-mannosylation is crucial for the biology of Mycobacterium tuberculosis but the key mannosylated protein(s) involved and its(their) underlying function(s) remain unknown. Here, we demonstrated that the M. tuberculosis mutant (Δpmt) deficient for protein O-mannosylation exhibits enhanced release of lipoarabinomannan (LAM) in a complex with LprG, a lipoprotein required for LAM translocation to the cell surface. We determined that LprG is O-mannosylated at a unique threonine position by mass spectrometry analyses of the purified protein. However, although replacement of this amino acid by an alanine residue completely abolished LprG O-mannosylation, the increased release of the LAM/LprG complex was preserved. We found that the increased secretion of this complex is due to enhanced LAM production in the Δpmt M. tuberculosis and M. smegmatis mutants relative to their wild-type counterparts. This abnormal release of LAM/LprG has functional consequences on the induction of inflammatory responses and provides a possible explanation for the reduced virulence of the M. tuberculosis Δpmt mutant.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
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Lipopolissacarídeos
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Fatores de Virulência
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Receptor 2 Toll-Like
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Inflamação
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Manose
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Mycobacterium tuberculosis
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article