Characterization of Phytase Producing Bacteria from Corn Weefil (Sitophilus zeamays).

Abstract

Phytic acid, the main storage form of phosphorus in seed, could not be digested by monogastric animal. The negatively charge phosphate of this compound strongly bind to metallic cations, proteins and polysaccharides making them insoluble and unavailable as nutritional factors. This compound can be hydrolyzed by phytases to released phosphate, inositol and nutrients. In the study about community of corn weevil bacteria some phytase producing bacterial isolates have been isolated. In this study, four of these isolates have been characterized. Morphological and physiological identification using microbactÔ showed that all four isolates have 99% similarity to Serratia rubidaea. Partial amplification of their 16S rRNA gene also showed highest identity to S. rubidaea (84%, 93%, 98%, and 80% respectively for KJ07, KJ13, KJ14, and KJ16). Employing from these result we proposed that all isolates were closely related to S. rubidaea. Using primers for phytase putative gene designed from Escherichia coli phytase, a 1500 bp DNA fragment was amplified. One of these fragments originated from KJ07 was chosen for further analysis. This fragment was cloned in E. coli and sequenced. Sequence analysis indicated that it showed similarity to phosphoenol piruvate protein phospho transferase (89%) and prolipoprotein diacylglycerol transferase (93%). Therefore, this strategy failed to isolate phytase gene from S. rubidaea.