Rastogi_2019_J.Med.Microbiol_68_1629

Reference

Title : Molecular characterization and immunogenic function of ML1899 (LipG) of Mycobacterium leprae - Rastogi_2019_J.Med.Microbiol_68_1629
Author(s) : Rastogi R , Kaur G , Maan P , Bhatnagar A , Narang T , Dogra S , Kaur J
Ref : J Med Microbiol , 68 :1629 , 2019
Abstract : Introduction. ML1899 is conserved in all mycobacterium sp. and is a middle member of mle-ML1898 operon involved in mycolic acid modification.Aim. In the present study attempts were made to characterize ML1899 in detail.Methodology. Bioinformatics tools were used for prediction of active-site residues, antigenic epitopes and a three-dimensional model of protein. The gene was cloned, expressed and purified as His-tagged protein in Escherichia coli for biophysical/biochemical characterization. Recombinant protein was used to treat THP-1 cells to study change in production of nitric oxide (NO), reactive oxygen species (ROS), cytokines and chemokines using flowcytometry/ELISA.Results. In silico analysis predicted ML1899 as a member of alpha/beta hydrolase family with GXSXG-motif and Ser126, His282, Asp254 as active-site residues that were confirmed by site-directed mutagensis. ML1899 exhibited esterase activity. It hydrolysed pNP-butyrate as optimum substrate at pH 8.0 and 50 degrees C with 5.56 microM(-1) min(-1) catalytic efficiency. The enzyme exhibited stability up to 60 degrees C temperature and between pH 6.0 to 9.0. K m, V max and specific activity of ML1899 were calculated to be 400 microM, 40 micromoles min(-1) ml(-1) and 27 U mg(-) (1), respectively. ML1899 also exhibited phospholipase activity. The protein affected the survival of macrophages when treated at higher concentration. ML1899 enhanced ROS/NO production and up-regulated pro-inflammatory cytokines and chemokine including TNF-alpha, IFN-gamma, IL-6 and IL-8 in macrophages. ML1899 was also observed to elicit humoral response in 69 % of leprosy patients.Conclusion. These results suggested that ML1899, an esterase could up-regulate the immune responses in favour of macrophages at a low concentration but kills the THP-1 macrophages cells at a higher concentration.
ESTHER : Rastogi_2019_J.Med.Microbiol_68_1629
PubMedSearch : Rastogi_2019_J.Med.Microbiol_68_1629
PubMedID: 31553301
Gene_locus related to this paper: mycle-lipG

Related information

Gene_locus related to this paper: mycle-lipG

Citations formats

Rastogi R, Kaur G, Maan P, Bhatnagar A, Narang T, Dogra S, Kaur J (2019)
Molecular characterization and immunogenic function of ML1899 (LipG) of Mycobacterium leprae
J Med Microbiol 68 :1629

Rastogi R, Kaur G, Maan P, Bhatnagar A, Narang T, Dogra S, Kaur J (2019)
J Med Microbiol 68 :1629