Topclass Journal of Microbiology Vol. 1(4) Pp. 67-73, 26 Dec. 2013 Available online at http://www.topclassglobaljournals.org ISSN 2315-8832 ©2013 Topclass Global Journals Submitted 26/7/2013 Accepted 21/9/2013 Full Length Research Article Production of alkaline phosphatase from newly isolated Aspergillus fumigatus EFRL05 Abdul Sattar Qureshi * , Surhan Marium, Imrana Khushk and Muhammad Aqeel Bhutto Institute of Biotechnology and Genetic Engineering, University of Sindh, Jamshoro, Pakistan ******************************************************************************************************************************* Abstract Three fungal strains capable of secreting extracellular alkaline phosphatase (ALPase) were isolated from soil. A. fumigatus EFRL 05 produced the highest yield of ALPase among the isolates. The cultural conditions were optimized for maximum ALPase production. A. fumigatus EFRL 05 culture maintained ~ 2273 U/ml when initial pH was adjusted to 8.0 at 40°C for 96 h under optimized conditions medium containing: 2.0% molasses and 1.0% corn steep liquor as carbon and nitrogen sources respectively. This study can be a platform for large scale ALPase production. Key words: Alkaline phosphatase (ALPase), molasses, corn steep liquor and submerged fermentation. ******************************************************************************************************************************* INTRODUCTION Alkaline phosphatase ALPase; Orthophosphate monoester phosphohydrolases (optimum at alkaline pH) catalyzes the phosphomonoesters from number of biomolecules such as; DNA, RNA, protein alkaloids, phosphate esters and anhydrides of phosphoric acid (Kobori et al., 1984; Trowsdale et al., 1990). ALPase is described as homodimeric metallo-dependent with two Zn +2 and one Mg +1 ion, nonspecific phosphomonoesterase (Trowsdale et al., 1990; Posen 1967; Park et al., 1999). Phosphatases have generally been classified as ALPase (EC 3.1.3.1) with optimum pH activity >8.0 and AcP (EC 3.1.3.2) with optimum pH <6.0 (De Araújo et al., 1976; Gargova et al., 2006).The fact that they are widely found in nature, from bacteria to mammals indicates that APs are included in fundamental biochemical processes (Posen 1967). Despite the fact that their physiological function is still not clear, their induced production under inorganic phosphate starvation in many species especially prokaryotic organisms indicates its vital role in the phosphate metabolism. In mammals, they are linked with transport mechanisms (McComb et al., 1979). ALPase is the most significant enzyme of microbial cell, which breaks down phosphoester to release inorganic phosphate (Pi) (Qureshi et al., 2010). Phosphate is the major source of energy in the cell, which is obtained from nucleic acids, phosphorylated sugars and proteins (De Parada et al., 1996). Phosphatase family shows clear cut diversity in their structure and function regarding to substrate specificity, sub-unit size and metal ion requirements (De Parada et al., 1996). Alkaline phosphatases with monomeric subunit are having the size of 15.5 kDa up to 160 kDa, (Fitt and Peterkin 1976; Goldman et al., 1990) while others having multiple sub units like trimeric proteins from Thermus aquaticus are 143 kDa (De Parada et al., 1996). Stable microbial alkaline phosphatases can be used in molecular biology, for recombinant DNA Corresponding Author’s Email: asattar_78@hotmail.com