TY - JOUR
T1 - Characterization of protein acyltransferase function of recombinant purified GlnA1 from Mycobacterium tuberculosis
T2 - A moon lighting property
AU - Baghel, Anil S.
AU - Tandon, Rashmi
AU - Gupta, Garima
AU - Kumar, Ajit
AU - Sharma, Raman K.
AU - Aggarwal, Neha
AU - Kathuria, Abha
AU - Saini, Neeraj K.
AU - Bose, Mridula
AU - Prasad, Ashok K.
AU - Sharma, Sunil K.
AU - Nath, Mahendra
AU - Parmar, Virinder S.
AU - Raj, Hanumantharao G.
N1 - Funding Information:
We acknowledge financial support from Department of Biotechnology, Government of India, New Delhi.
PY - 2011/12/20
Y1 - 2011/12/20
N2 - The protein acetyltransferase (MTAase) function of glutamine synthetase of Mycobacterium smegmatis was established earlier. In this paper, studies were undertaken to examine MTAase function of recombinant glutamine synthetase (rGlnA1) of Mycobacterium tuberculosis, which showed >80% similarity with M. smegmatis GlnA. The specificity of MTAase to several acyl derivative of coumarins was examined. The results clearly indicated that MTAase exhibited differential specificities to several acyloxycoumarins. Further, MTAase was also found capable of transferring propionyl and butyryl groups from propoxy and butoxy derivatives of 4-methylcoumarin. These observations characterized MTAase in general as a protein acyltransferase. MTAase catalyzed acetylation of GST by 7,8-diacetoxy-4-methylcoumarin (DAMC), a model acetoxy coumarin was confirmed by MALDI-TOF-MS as well as western blot analysis using acetylated lysine polyclonal antibody. In order to validate the active site of rGlnA1 for TAase activity, effect of DAMC and L-methionine-S-sulfoximine (MSO) on GS and TAase activity of rGlnA1 were studied. The results indicated that the active sites of GS and TAase were found different. Acetyl CoA, a universal biological acetyl group donor, was also found to be a substrate for MTAase. These results appropriately characterize glutamine synthetase of Mtb exhibiting transacylase action as a moonlighting protein.
AB - The protein acetyltransferase (MTAase) function of glutamine synthetase of Mycobacterium smegmatis was established earlier. In this paper, studies were undertaken to examine MTAase function of recombinant glutamine synthetase (rGlnA1) of Mycobacterium tuberculosis, which showed >80% similarity with M. smegmatis GlnA. The specificity of MTAase to several acyl derivative of coumarins was examined. The results clearly indicated that MTAase exhibited differential specificities to several acyloxycoumarins. Further, MTAase was also found capable of transferring propionyl and butyryl groups from propoxy and butoxy derivatives of 4-methylcoumarin. These observations characterized MTAase in general as a protein acyltransferase. MTAase catalyzed acetylation of GST by 7,8-diacetoxy-4-methylcoumarin (DAMC), a model acetoxy coumarin was confirmed by MALDI-TOF-MS as well as western blot analysis using acetylated lysine polyclonal antibody. In order to validate the active site of rGlnA1 for TAase activity, effect of DAMC and L-methionine-S-sulfoximine (MSO) on GS and TAase activity of rGlnA1 were studied. The results indicated that the active sites of GS and TAase were found different. Acetyl CoA, a universal biological acetyl group donor, was also found to be a substrate for MTAase. These results appropriately characterize glutamine synthetase of Mtb exhibiting transacylase action as a moonlighting protein.
KW - 7,8-Diacetoxy-4-methylcoumarin
KW - Glutamine synthetase
KW - Mycobacterium tuberculosis
KW - Protein acyltransferase
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U2 - 10.1016/j.micres.2011.02.001
DO - 10.1016/j.micres.2011.02.001
M3 - Article
C2 - 21411303
AN - SCOPUS:82755187367
SN - 0944-5013
VL - 166
SP - 662
EP - 672
JO - Microbiological Research
JF - Microbiological Research
IS - 8
ER -
