Characterization of the fucosylation pathway in the biosynthesis of glycopeptidolipids from Mycobacterium avium complex.

نویسندگان

  • Yuji Miyamoto
  • Tetsu Mukai
  • Yumi Maeda
  • Noboru Nakata
  • Masanori Kai
  • Takashi Naka
  • Ikuya Yano
  • Masahiko Makino
چکیده

The cell envelopes of several species of nontuberculous mycobacteria, including the Mycobacterium avium complex, contain glycopeptidolipids (GPLs) as major glycolipid components. GPLs are highly antigenic surface molecules, and their variant oligosaccharides define each serotype of the M. avium complex. In the oligosaccharide portion of GPLs, the fucose residue is one of the major sugar moieties, but its biosynthesis remains unclear. To elucidate it, we focused on the 5.0-kb chromosomal region of the M. avium complex that includes five genes, two of which showed high levels of similarity to the genes involved in fucose synthesis. For the characterization of this region by deletion and expression analyses, we constructed a recombinant Mycobacterium smegmatis strain that possesses the rtfA gene of the M. avium complex to produce serovar 1 GPL. The results revealed that the 5.0-kb chromosomal region is responsible for the addition of the fucose residue to serovar 1 GPL and that the three genes mdhtA, merA, and gtfD are indispensable for the fucosylation. Functional characterization revealed that the gtfD gene encodes a glycosyltransferase that transfers a fucose residue via 1-->3 linkage to a rhamnose residue of serovar 1 GPL. The other two genes, mdhtA and merA, contributed to the formation of the fucose residue and were predicted to encode the enzymes responsible for the synthesis of fucose from mannose based on their deduced amino acid sequences. These results indicate that the fucosylation pathway in GPL biosynthesis is controlled by a combination of the mdhtA, merA, and gtfD genes. Our findings may contribute to the clarification of the complex glycosylation pathways involved in forming the oligosaccharide portion of GPLs from the M. avium complex, which are structurally distinct.

متن کامل
منابع مشابه

The mycobacterial glycopeptidolipids: structure, function, and their role in pathogenesis.

Glycopeptidolipids (GPLs) are a class of glycolipids produced by several nontuberculosis-causing members of the Mycobacterium genus including pathogenic and nonpathogenic species. GPLs are expressed in different forms with production of highly antigenic, typeable serovar-specific GPLs in members of the Mycobacterium avium complex (MAC). M. avium and M. intracellulare, which comprise this comple...

متن کامل

Isolation and expression of a gene cluster responsible for biosynthesis of the glycopeptidolipid antigens of Mycobacterium avium.

Bacteria within the Mycobacterium avium complex are prominent in the environment and are a source of serious disseminated infections in patients with AIDS. Serovars of the M. avium complex are distinguished from all other mycobacteria and from one another by the presence of highly antigenic glycolipids, the glycopeptidolipids, on their surfaces. A genomic library of DNA from serovar 2 of the M....

متن کامل

Fast atom bombardment mass spectrometry of Mycobacterial glycopeptidolipid antigens: Structural characterization by charge remote fragmentation.

Mycobacteria contain species- and type-specific antigens. Among them, glycopeptidolipids are present in medically relevant organisms belonging to Mycobacterium avium or M. fortuitum complexes. Fast-a tom bombardment mass spectrometry of glycopeptidolipids has proven to be difficult. In this article the cationization method with a metanitrobenzyl alcohol matrix, doped with sodium iodide, is desc...

متن کامل

SERA FROM SYPIllLI ATIC PATIENTS CROSS REACT WITH SPECIFIC GLYCOPEPTIDOLIPID AND WHOLE LIPID EXTRACT OF MYCOBACTERIUM AVIUM COMPLEX IN AN ANTICARDI OLIPIN ANTIBODY TEST

متن کامل

Genomic Characterization of the Vaccinal Strain of Mycobacterium Avium Subspecies Paratuberculosis (MAP) 316F by MIRU-VNTR

Abstract        Background and Objective: Paratuberculosis is a chronic granulomatous enteritis of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). this study aimed to characterize the genome of the MAP 316F strain.       Methods: The MAP 316F strain was subjected to the PCR-F57 and PCR-IS900 experi...

متن کامل

ذخیره در منابع من

ذخیره در منابع من قبلا به منابع من ذحیره شده

{@ msg_add @}


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

متن کامل
عنوان ژورنال:
  • Journal of bacteriology

دوره 189 15  شماره 

صفحات  -

تاریخ انتشار 2007