Cloning, Sequencing and Characterization of a Novel Phosphatase Gene, phoI, from Soil Bacterium Enterobacter sp. 4

Abstract

A gene, phoI, coding for a phosphatase from Enterobacter sp. 4 was cloned in Escherichia coli and sequenced. Analysis of the sequence revealed one open reading frame (ORF) that encodes a 269-amino acid protein with a calculated molecular mass of 29 kDa. PhoI belongs to family B acid phosphatase and exhibits 49.4% identity and 62.4% homology to the hel gene from Heamophilus influenzae, which encoded an outer membrane protein (P4). The optimum pH and temperature for phosphatase activity were pH 5.5 and 40 degrees C, respectively. Its specific activity on rho-nitrophenyl phosphatate was 70 U/mg at pH 5.5 and 40 degrees C. Enzyme activity was inhibited by Al3+, EDTA, and DTT, but fivefold activated by Cu2+ ion (350 U/mg). PhoI showed a strong synergistic effect when used with a purified E. coli phytase, AppA, to estimate combination effects.

Biochemical Characterization of an Acid Phosphatase fromThermus thermophilus

“…Several studies have been carried out to demonstrate the synergistic effect of using both phytase and acid phosphatase in the form of an enzymatic cocktail in animal feed supplements. 17,26) Therefore, in order to be applied as a commercial feed supplement for livestock, this recombinant acid phosphatase might have to be used synergistically with phytase, instead of as a substitution for phytase.…”

“…16) Alternatively, bacterial nonspecific acid phosphatase alone or in combination with phytase can be used as feed supplements in the livestock industry to hydrolyze phytate into myo-inositol and phosphoric acid. 13,17) Phytate is the major form of phosphorous storage in the seeds of cereal crops. It acts as an antinutrient due to its chelation of divalent metals and proteins, diminishing the bioavailability of proteins and nutritionally important minerals.…”

Phytohormonal Activity of Immobilized Cells of Salt-Tolerant Cotton Rhizobacteria After Long Term Storage

“…The most highly effective producers of auxins are found among microorganisms living in the rhizosphere and phyllosphere of plants [2][3][4]. The maximum amount of IAA is formed by bacteria in the stationary phase of growth, and ammonium ions and glutamine inhibit the biosynthesis of IAA [5,6]. In plants, IAA binds to sugars, amino acids, proteins, forming spare forms, from which the phytohormone is released if necessary.…”