Title : Cloning, expression and characterization of Pullulanase enzyme from locally isolated klebsiella pneumoniae
Pullulanase is a potential candidate for bioremediation. It has found potential applications in medical, dental, pharmaceutical, food, baking, dishwashing, laundry and textile industry. Pullulanase act on α-1,6 glycosidic bonds and produce maltotriose as a major product. The recombinant Klebsiella pneumoniae IIB Pullulanase E shows similarity with Klebsiella pneumoniae strain 1864 Pullulanase. The pullulanase from Klebsiella Pneumoniae was amplified using PulE primers, cloned into E. coli with pJET1.2 as a cloning vector, expressed into BL21 with pET21a (+) as an expression vector, purified using NH4(SO)4 precipitation 60% and dialysis, CM-Sepharose fast flow, Sephadex G-150. ~1.5Kb was the size of the amplified product. 1.49Kb was the confirmed size of the gene by gene sequencing and multiple alignment. The total protein content of the crude enzyme solution was 54mg while the total protein content of purified protein was 2.24mg with 420.98U total enzyme activity, specific activity of 187.93U/mg having purification factor of 2.87fold with 11.91% enzyme recovery. 45ºC was the optimum temperature for PulE and it was stable up to 40ºC. It has an optimum pH of 6.5 with pH stability ranging from 6-7.5. It is a demanding candidate for potential industrial applications due to its features.