Bacillus phytase

Kerovuo J, Tynkkynen S (2000) Expression of Bacillus subtilis phytasem Lactobacillus plantarum 755. Lett Appl Microbiol 30 325-329 Kerovuo J, Rouvinen J, Hatzack F (2000) Analysis of myo-inositol hexakisphosphate hydrolysis by bacillus phytase. indication of a novel reaction mechanism. Biochem J 352 623-628 Kitahata S, Taniguchi M, Beltran SD, Sugimoto T, Okada S (1983) Purification and some properties of cyclodextrinase from Bacillus coagulans. Agric Biol Chem 47 1441-1447... 

The pH optima of a number of phytases ranged between 2.2 (in the yeast Pichia far-inosa) and 7.5 (in Bacillus subtilis and germinated Phaseolus aureus), whereas the phytase of Rhizopus oligosporus NRRL 2710 exhibited an optimum at pH 5.6 (Nayini and Markakis, 1986). The phytases of Asper-... 

Activation energy values for the hydrolysis of myo-inositol hexakisphosphate and of esters with lower phosphate content were between 35.6 kJ/mol in germinated Phaseolus aureus (Mandal et al., 1972) and 50.2 kJ/mol in wheat bran (Nagai and Funahashi, 1962). The optimum temperature for the enzymatic hydrolysis of myo-inositol hexakisphosphate varies among phytases between 45 and 57°C (Nayini and Markakis, 1986), and even up to 60°C for the phytase of Bacillus subtilis (Powar and Jagannathan, 1982). 

The lowest and the highest values for myo-inositol hexakisphosphate hydrolysis were reported in phytases of Aspergillus ficuum (pH 5.3, 0.01 mM) and in that of germinated Phaseolus aureus (0.65 mM), respectively. The highest values reported were of wheat bran phytase towards myoinositol tetrakis- and trisphosphate (5 mM see Nayini and Markakis, 1986). K and K, values for the enzymatic hydrolysis of myoinositol hexakisphosphate by different Bacillus spp. were determined to be approximately 0.44 mM and 18.6/s, respectively. The affinity of myo-inositol pentakisphosphate for the phytase enzymes and their maximal rates of hydrolysis were lower (K = 0.50-0.76 mM 7.4-16/s) than that of myo-inositol hexakisphosphate (Greiner et al., 2002). 

Phytase Aspergillus sp., Aspergillusficuum, Penicilliumfuniculosum, Bacillus sp., Pseudomonas, Xanthomonas oryzae... 

Phytase from fungi has been shown to be extremely compatible with the low pH conditions of the animal gastric tract (Jongbloed et al. 1992), but also phytases from bacteria, such as Bacillus subtilis, are being developed for use as a feed additive (Kerovuo et al. 2000 Park et al. 1999 Kerovuo and Tynkkynen 2000). 

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