Cloning, Expression, and Characterization of Thermotolerant Manganese Superoxide Dismutase from Bacillus sp. MHS47

Abstract

A superoxide dismutase gene from thermotolerant Bacillus sp. MHS47 (MnSOD47) was cloned, sequenced, and expressed. The gene has an open reading frame of 612 bp, corresponding to 203 deduced amino acids, with high homology to the amino acid sequences of B. thuringiensis (accession no. EEN01322), B. anthracis (accession no. NP_846724), B. cereus (accession no. ZP_04187911), B. weihenstephanensis (accession no. YP_001646918), and B. pseudomycoides. The conserved manganese-binding sites (H28, H83, D165, and H169) show that MnSOD47 has the specific characteristics of the manganese superoxide dismutase (MnSOD) enzymes. MnSOD47 expressed an enzyme with a molecular weight of approximately 22.65 kDa and a specific activity of 3537.75 U/mg. The enzyme is active in the pH range 7–8.5, with an optimum pH of 7.5, and at temperatures in the range 30–45 °C, with an optimum temperature of 37 °C. Tests of inhibitors and metal ions indicated that the enzyme activity is inhibited by sodium azide, but not by hydrogen peroxide or potassium cyanide. These data should benefit future studies of MnSODs in other microorganisms and the biotechnological production of MnSOD47, and could also be used to develop a biosensor for the detection of antioxidants and free radical activity. In the future, this basic knowledge could be applicable to the detection of cancer risks in humans and therapeutic treatments.

Cloning, expression and biochemical characterization of recombinant superoxide dismutase from Antarctic psychrophilic bacterium Pseudoalteromonas sp. ANT506

“…Bacillus sp. MHS47 Mn‐SOD had conserved amino acids of WEHAYY and conserved Mn‐binding sites: His 28 , His 83 , Asp 165 , and His 169 . Mn‐SOD signature (WEHAYY) and four conserved amino acids for Mn‐binding (His 54 , His 102 , Asp 186 , and His 190 ) were observed in B. tabaci Mn‐SOD .…”

Unique Characteristics of Recombinant Hybrid Manganese Superoxide Dismutase from Staphylococcus equorum and S. saprophyticus

“…Examples from the first group are SOD from T. thermophilus HB27 (pH 5.0-7.0) [21], Thermothrix sp (pH 8.0-10.0) [8], and Bacillus sp. MHS47 (pH 7.0-8.5) [9]. The second group is represented by SOD from Thermus sp.…”

“…Interestingly, few SODs can also be cambialistic, which means that the type of metal installed is exchangeable [20]. Further, SODs demonstrate stability against various environmental stress, particularly those originated from thermophilic or hyperthermophilic microorganisms [8][9][10][11][12][13][14]21]. Thermostable SOD are of interest for application such as sun cream and for its stability during production, formulation, shipping, and storage.…”

“…Many SODs are reported to display low activity at low pH [7][8][9][10][11][12][13][14] and to cope with that, strategies have been developed to improve the enzyme stability towards extreme pH condition. Immobilization the enzyme to nanoparticles appears as an attractive alternative because it prolongs and extends the use of the enzyme, as demonstrated in stabilization of SOD from Thermus thermophillus wl [15].…”

Transcript profiles of mitochondrial and cytoplasmic manganese superoxide dismutases in Exopalaemon carinicauda under ammonia stress

“…Superoxide dismutase (SOD) plays a critical role in the antioxidant defense pathway against oxidative stress (Fridovich, 1995;Chandra et al, 2000;Areekit et al, 2011). This enzyme catalyzes a dismutation reaction in which the superoxide radical is converted to hydrogen peroxide and molecular oxygen (Pipe et al, 1993).…”