Identification of full length, splicing and cleavage products of SufB protein of SUF-complex of Mycobacterium tuberculosis

SufB, an Fe-S cluster assembly protein is critical for mycobacterial survival and virulence; but as a protein still at its nascent stage. SufB is interrupted by an intein sequence, which excises itself out from the full length protein post-translationally. Intein splicing is crucial for the activation of SufB, where intein(I) is excised and final functional product is generated by the ligation of flanking regions, known as Extein or Ligated extein(LE). Functional SufB is coordinating with other Suf proteins of SUF complex to generate Fe-S cluster. These are important for the central metabolism, gene expression, DNA repair etc. During the process of splicing, SufB has a tendency to generate off pathway products as N-cleavage (NC) and N-Extein (NE). In this project we have confirmed the identities of Mycobacterium tuberculosis full length SufB protein (precursor/p), SufB Intein (i), SufB Extein (ligated Extein/le), N-terminal cleavage product (nc) and N-extein (ne) by MALDI TOF/TOF mass spectrometry via gel based proteomics method .