TY  - JOUR
AU  - Kovacevic, S
AU  - Anderson, D
AU  - Morita, YS
AU  - Patterson, J
AU  - Haites, R
AU  - McMillan, BNI
AU  - Coppel, R
AU  - McConville, MJ
AU  - Billman-Jacobe, H
Y2  - 2014/05/21
Y1  - 2006/04/07
SN  - 0021-9258
UR  - http://hdl.handle.net/11343/26170
AB  - All species of Mycobacteria synthesize distinctive cell walls that are rich in phosphatidylinositol mannosides (PIMs), lipomannan (LM), and lipoarabinomannan (LAM). PIM glycolipids, having 2-4 mannose residues, can either be channeled into polar PIM species (with 6 Man residues) or hypermannosylated to form LM and LAM. In this study, we have identified a Mycobacterium smegmatis gene, termed lpqW, that is required for the conversion of PIMs to LAM and is highly conserved in all mycobacteria. A transposon mutant, Myco481, containing an insertion near the 3' end of lpqW exhibited altered colony morphology on complex agar medium. This mutant was unstable and was consistently overgrown by a second mutant, represented by Myco481.1, that had normal growth and colony characteristics. Biochemical analysis and metabolic labeling studies showed that Myco481 synthesized the complete spectrum of apolar and polar PIMs but was unable to make LAM. LAM biosynthesis was restored to near wild type levels in Myco481.1. However, this mutant was unable to synthesize the major polar PIM (AcPIM6) and accumulated a smaller intermediate, AcPIM4. Targeted disruption of the lpqW gene and complementation of the initial Myco481 mutant with the wild type gene confirmed that the phenotype of this mutant was due to loss of LpqW. These studies suggest that LpqW has a role in regulating the flux of early PIM intermediates into polar PIM or LAM biosynthesis. They also suggest that AcPIM4 is the likely branch point intermediate in polar PIM and LAM biosynthesis.
N1  - application/pdf
LA  - English
PB  - AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
KW  - Biochemistry and Cell Biology not elsewhere classified ; Biological Sciences
T1  - Identification of a novel protein with a role in lipoarabinomannan biosynthesis in mycobacteria
DO  - 10.1074/jbc.M511709200
IS  - Journal of Biological Chemistry
VL  - 281
IS  - 14
SP  - 9011-9017
L1  - /bitstream/handle/11343/26170/115933_4975.pdf?sequence=1&isAllowed=n
ER  -