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Identification of M. tuberculosis Rv3441c and M. smegmatis MSMEG_1556 and essentiality of M. smegmatis MSMEG_1556.

ABSTRACT: The normal growth of mycobacteria attributes to the integrity of cell wall core which consists of peptidoglycan (PG), arabinogalactan (AG) and mycolic acids. N-acetyl glucosamine (GlcNAc) is an essential component in both PG and AG of mycobacterial cell wall. The biosynthetic pathway for UDP-N-acetylglucosamine (UDP-GlcNAc), as a sugar donor of GlcNAc, is different in prokaryotes and eukaryotes. The conversion of glucosamine-6-phosphate to glucosamine-1-phosphate, which is catalyzed by phosphoglucosamine mutase (GlmM), is unique to prokaryotes. Bioinformatic analysis showed that Msm MSMEG_1556 and Mtb Rv3441c are homologous to Ec GlmM. In this study, soluble Msm MSMEG_1556 protein and Mtb Rv3441c protein were expressed in E. coli BL21(DE3) and their phosphoglucosamine mutase activity were detected. In order to further investigate the essentiality of MSMEG_1556 for the growth of M. smegmatis, we generated a conditional MSMEG_1556 knockout mutant, which harbored thermo-sensitive rescue plasmid carrying Mtb Rv3441c. As the rescue plasmid was unable to complement MSMEG_1556 deficiency at 42 °C, MSMEG_1556 knockout mutant did not grow. The dramatic morphological changes of MSMEG_1556 knockout mutant after temperature shift from 30 °C to 42 °C have been observed by scanning electron microscope. These results demonstrated that MSMEG_1556 is essential for growth of M. smegmatis. This study provided evidence that GlmM enzyme could be as a potential target for developing anti-tuberculosis drugs.

SUBMITTER: Li S

PROVIDER: S-EPMC3414508 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Identification of M. tuberculosis Rv3441c and M. smegmatis MSMEG_1556 and essentiality of M. smegmatis MSMEG_1556.

Li Shuang S Kang Jian J Yu Wendan W Zhou Yan Y Zhang Wenli W Xin Yi Y Ma Yufang Y

PloS one 20120808 8

The normal growth of mycobacteria attributes to the integrity of cell wall core which consists of peptidoglycan (PG), arabinogalactan (AG) and mycolic acids. N-acetyl glucosamine (GlcNAc) is an essential component in both PG and AG of mycobacterial cell wall. The biosynthetic pathway for UDP-N-acetylglucosamine (UDP-GlcNAc), as a sugar donor of GlcNAc, is different in prokaryotes and eukaryotes. The conversion of glucosamine-6-phosphate to glucosamine-1-phosphate, which is catalyzed by phosphogl ...[more]

PMID: 22905172

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Dataset Information

Identification of M. tuberculosis Rv3441c and M. smegmatis MSMEG_1556 and essentiality of M. smegmatis MSMEG_1556.

Publications

Identification of M. tuberculosis Rv3441c and M. smegmatis MSMEG_1556 and essentiality of M. smegmatis MSMEG_1556.

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