Vol. 7, Issue 1 (2018)

Author(s):
Sharad Thakur, Seema Madhumal Thayil and Anup Kumar Kesavan

Abstract:
Physiological role of iron metal is well documented as it is essential as a co-factor for the enzymes involved in the basic bio-chemical and metabolic reactions necessary for the microorganism like cellular respiration, as a part of the components of electron transport chain and for the enzymes involved in DNA replication. Micro-organisms have in place eloquent methods for iron metal uptake. Microorganisms employs a battery of iron, Fe²⁺, sensing genes, which are essential for quenching, acquiring and assimilating iron metal from the micro-organisms milieu and thus, important for surviving successfully inside the host. The DtxR protein family is a widely established family of transcriptional regulators influencing transcription of other essential genes too. Transcriptional regulators from DtxR family are strictly iron metal dependant, though in-vitro, these metallo-regulators are known to bind to other divalent cations too. DtxR, metallo-regulator was first isolated from Corynebacterium diphtheriae, where it influences the synthesis of diptheriae toxin gene, tox, in the presence of iron metal. DtxR is a universal transcriptional regulator present in other micro-organisms too. The present study was designed to amplify, express, purify the DtxR protein and study it’s binding characteristics with various divalent cations through bio-physical technique. Controlling iron levels inside the micro-organism is very essential as its excess leads to the oxidative stress and deficiency impedes micro-organisms survival and both the conditions are deleterious for the micro-organism.