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Query: EC:3.1.3.8 (
phytase
)
1,997
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Phytase (myo-inositol hexakisphosphate phosphohydrolase;
EC 3.1.3.8
or 3.1.3.26) was purified from rat intestinal mucosa. The purified enzyme preparation exhibited two protein bands on SDS-polyacrylamide gel electrophoresis with estimated molecular masses of 70 kDa and 90 kDa. Rabbit antisera prepared against the 90K subunit cross-reacted with the 70K subunit on immunoblotting. The peptide maps of the 70K and 90K subunits were similar, and the N-terminal amino acid sequences of the two subunit proteins were almost identical. Treatments to remove sugar moieties from the proteins showed that the two subunit proteins had different oligosaccharide chains, although the difference in their molecular masses was not due to the difference in their oligosaccharide compositions. The purified enzyme also showed activity of alkaline phosphatase (orthophosphoric monoester phosphohydrolase; EC 3.1.3.1), but the properties of the two enzyme activities were different; the optimum pH for
phytase
activity was 7.5, while that for alkaline phosphatase was 10.4. Phytase activity did not necessarily require divalent cations, while Mg2+ was essential for alkaline phosphatase activity.
Phenylalanine
, a specific inhibitor of intestine-type alkaline phosphatase had no effect on the
phytase
activity.
...
PMID:Purification and characterization of phytase from rat intestinal mucosa. 165 10
Five barrows of approximately 45 kg BW, fitted with post-valvular T-cecum cannulas at the ileo-cecal junction, were assigned randomly to five treatments (5 x 5 Latin square design) to assess the effect of microbial
phytase
and feeding regimen (frequency and level) on the apparent digestibilities (total tract [ATTD] and ileal [AID]) and retention of nutrients. A corn-tapioca-soybean meal diet of low intrinsic
phytase
activity, containing no added inorganic P, was fed either without or with microbial
phytase
from Aspergillus niger var. Van Tieghem (800
phytase
units/kg of diet) at different feeding frequencies (once, twice, or seven times per day) and feeding levels (2.3 vs 2.8 times the maintenance requirement for ME, i.e., 418 kJ ME/BW.75). Microbial
phytase
enhanced significantly the ATTD of DM, OM, CP, Ca, total P, and amino acids (except for cystine and proline). Also, the AID of total P, phytic acid, methionine, and arginine was increased (P < .05 or .01). As a consequence of adding this enzyme, the retention (grams/day) of N, Ca, and P was greater (P < .01) and their daily excretion was diminished by 5.5, 2.2, and 1.9 g/d, respectively. The feeding level exerted a minor effect on the ATTD and AID (except for methionine and cystine), although the retention (grams/day) of N, Ca, and P was greater (P < .01) at the higher level of feeding. The feeding frequency influenced significantly the ATTD of Ca, tryptophan, and isoleucine and the AID of phytic acid, cystine, arginine, isoleucine, and
phenylalanine
. Also, N retention (grams/day) was reduced in pigs fed once daily (P < .01).
...
PMID:Apparent digestibility and retention of nutrients bound to phytate complexes as influenced by microbial phytase and feeding regimen in pigs. 813 79
The effect of microbial
phytase
supplementation on CP and amino acid (AA) digestibility was investigated in a 28-d trial using 360 sexed, day-old broiler chickens fed corn-soybean meal diets. The experimental design was a completely randomized one with a 3 x 2 factorial arrangement of treatments. The variables included P and Ca levels and
phytase
: P and Ca levels were: normal P-normal Ca [0.45% available P (Pa), 1.0% Ca], low P-normal Ca (0.35% Pa, 1.0% Ca), and low P-low Ca (0.35 Pa and 0.6% Ca); and
phytase
at 0 and 600 U/kg diet. Phytase supplementation increased body weight gain (P < 0.014) and feed intake (P < 0.004) at 19 d in male chickens; in females,
phytase
increased (P < 0.012) only body weight gain at 19 d. The low P-normal Ca diet reduced (P < 0.05) feed intake and body weight gain in both sexes at 7, 14, and 19 d, compared to the normal P-normal Ca diet; the reduction of Ca in the low P diet prevented the above depression, resulting in body weight gain and feed intake to a level comparable to that of the normal P-normal Ca diet. Microbial
phytase
supplementation had no effect (P < 0.065) on the apparent ileal digestibility (AID) of CP or any AA except Met and
Phe
in male broiler chickens. In females, adding
phytase
increased the AID of all AA except Lys, Met,
Phe
, and Pro. The low P-normal Ca diet reduced (P < 0.05) the AID of
Phe
, Asp, and Ser in male chickens and reduced the AID of all the AA except Met and Pro in females compared to the normal P-normal Ca diet. The reduction of Ca in the low P diet prevented the depression of the AID of the AA caused by the low P-normal Ca diet, resulting in AID of AA having a level comparable to that of the normal P-normal Ca diet in both sexes. Phytase supplementation did not have any effect (P > 0.05) on apparent "fecal" digestibility (AFD) of CP or any of the AA in male chickens; however, in female chickens it increased the AFD of Thr, Asp, Glu, and Ser. In summary,
phytase
supplementation increased growth performance in both sexes; increased AID and AFD of most of the AA, particularly in female chickens. The optimum growth performance and AA digestibilities were obtained with the lowest input of resources, in the low P-low Ca diet supplemented with microbial
phytase
.
...
PMID:Apparent digestibility of protein and amino acids in broiler chickens fed a corn-soybean diet supplemented with microbial phytase. 943 93
An amino acid deletion assay, a protein efficiency ratio (PER) assay, and a slope-ratio growth assay were used to establish the limiting order of AA, and to determine the effects of microbial
phytase
on protein utilization in corn gluten meal (CGM) fed to chicks during the period of 8 to 21 d posthatching. In Assay 1, a 12% CP CGM diet was fortified with AA to fulfill the digestible AA ideal profile (only
Phe
+ Tyr, Leu, and Pro exceeded requirements) for young chicks. Amino acids were then individually deleted, and all diets were fortified to 23% CP, with Glu varying as necessary. A Met-fortified 23% CP corn-soybean meal diet served as a positive control. No weight gain or feed efficiency differences were observed between the fully fortified CGM basal diet and the corn-soybean meal positive-control diet. The limiting order of AA established in CGM was 1) Lys, 2) Trp, 3) Arg, 4) Thr, 5) Val, 6) Ile, 7) His, 8) cystine, and 9) Met. In Assay 2, diets with 10% CP furnished by CGM or casein were fed in the presence and absence of 1,200 U/kg
phytase
. A protein source x
phytase
interaction (P < 0.05) was observed for weight gain, gain:feed, and PER, indicating positive responses to
phytase
when casein was fed but negative responses to
phytase
when CGM was fed. In Assay 3, graded levels of protein (8, 16, and 24% CP) furnished by CGM were fed in the presence and absence of 1,200 U/kg
phytase
. Weight gain and gain:feed increased linearly (P < 0.05) as a function of protein intake, but
phytase
supplementation had no effect on weight gain or gain:feed slopes. These results indicate that 1,200 U/kg
phytase
did not increase either CP or AA utilization in CGM for young chicks.
...
PMID:Limiting order of amino acids and the effects of phytase on protein quality in corn gluten meal fed to young chicks. 1094 2
Phosphatase activities associated with the intestinal brush border membrane (BBM) of the rat were examined histochemically in relation to the characteristic environment of the intestine, where luminal pH fluctuates drastically between alkaline and acid pH ranges. Special attention was given to intestinal alkaline phosphatase (IALP) and
phytase
on the BBM. Whole body fresh-frozen sections of young rats and their rapidly frozen and freeze-substituted small intestines, embedded in Technovit 7100, were processed for the histochemical demonstration of phosphatase activity at three different pH values (9.2, 7.3, and 5.2), representing the deviation of luminal pH in vivo. Either an azo-dye method or lead-salt method was employed using naphthol AS-MX phosphate and ATP as substrate, respectively. With the azo-dye method, intense phosphatase reactions were demonstrated along the BBM at all three pH ranges. Phosphatase reactions of the BBM at pH 9.2 and 7.3 were abolished by L(+)-
phenylalanine
, heat pre-treatment, and EDTA chelation although some reaction remained at pH 7.3 after the treatment with EDTA or L(+)-
phenylalanine
. Phosphatase reactions of the BBM at pH 5.2 were resistant to L(+)-
phenylalanine
, L(+)-tartrate, PCMB and EDTA chelation, implying that the characteristics of the enzyme responsible for phosphohydrolysis at acid pH values differed from those at higher pH values. The lead-salt method in which ATP was used as substrate revealed intense reactions--which were dependent on Mg++ and stimulated by Ca++ and resistant to L(+)
phenylalanine
--to be localized along the BBM at alkaline and neutral pH values, but not at acid pH values. In vitro experiments showed progressive hydrolysis of naphthol AS-MX phosphate by purified
phytase
at pH 5.2, in a dose-dependent manner, and suggested the possible involvement of
phytase
in the phosphatase reactions of the BBM at acid pH. These data indicate that the phosphatase reactions at alkaline and neutral pH values, associated with the BBM of the rat intestine, represent IALP and Mg++/ Ca++-ATPase, while those at acid pH appear to correspond to
phytase
activity, something which has not been demonstrated by histochemical methods despite the availability of extensive data based on biochemical analyses.
...
PMID:Phosphatase activities of rat intestinal enterocytes and their relation to diverse luminal pH, with special references to the possible localization of phytase along the brush border membrane. 1183 8
A strain Bacillus subtilis producing neutral
phytase
was screened from soil. The protein of
phytase
was purified by HPLC. Optimal pH value and temperature of the
phytase
for its activity were 7.5 and 55 degrees C, respectively. The Km values of the
phytase
for dodecasodium phytate under 37 degrees C was 0.19 mmol/L. The molecule weight of the
phytase
protein was determined as about 45 kD by SDS-PAGE. The N-terminal amino acids sequence of the
phytase
protein was determined as Lys-His-Lys-Leu-Ser-Asp-Pro-Tyr-His-
Phe
-Thr by amino acids sequence analysis.
...
PMID:[Purification and properties of neutral phytase form Bacillus subtilis]. 1254 26
Ten crossbred barrows (48.3 +/- 2.3 kg of initial BW) fitted with steered ileo-cecal valve cannulas were used to investigate the effects of supplemental microbial
phytase
on the apparent ileal digestibilities (AID) of AA, Ca, P, N, and DM, and the apparent total tract digestibilities of Ca, P, N, and DM. All diets were corn-soybean meal-based, and contained 0.44% Ca and 0.40% total P. Diets 1, 2, and 3 contained 12.0, 11.1, and 10.2% CP, respectively. Diets 4 and 5 had the same ingredient composition as diet 3, plus 250 and 500 U/kg
phytase
(Natuphos), respectively. Pigs were randomly allotted to 1 of 5 dietary treatments in a paired 5 x 5 Latin square with an extra period to test for carryover effects. Each 14-d period consisted of a 7-d adjustment followed by a 3-d total collection, a 12-h ileal digesta collection, a 3-d readjustment, and a second 12-h ileal digesta collection. Pigs were housed individually in metabolism pens (1.2 x 1.2 m). Water was supplied ad libitum, and feed was supplied at a level of 9% of the metabolic BW (BW(0.75)) per day in 2 equal daily feedings. As the dietary CP concentration increased, the AID of CP and all AA measured increased linearly (P < 0.05) with the exception of proline. In addition, the apparent total tract digestibilities (grams per day) and retention of N (grams per day) increased linearly (P < 0.01) with increasing CP levels. Supplementing diets with
phytase
increased the AID of Ca (P < 0.01), P (P < 0.001), CP (P = 0.07), and the AA (P < 0.10) Gly, Ala, Val, Ile, Thr, TSAA, Asp, Glu,
Phe
, Lys, and Arg. Protein and
phytase
response equations were generated for those AA affected (P < 0.10) by both CP level and
phytase
supplementation. Based on these equations, 500 U/kg of
phytase
can replace 0.52 percentage units of the dietary CP, which includes a 0.03 percentage unit improvement in Lys AID. The results of this study show that supplementing pig diets with microbial
phytase
improves CP and AA digestibilities in addition to Ca and P digestibilities.
...
PMID:Estimating equivalency values of microbial phytase for amino acids in growing and finishing pigs fitted with steered ileo-cecal valve cannulas. 1661 14
Two studies were conducted to determine the efficacy of an Escherichia coli-derived
phytase
(ECP) and its equivalency relative to inorganic phosphorus (iP) from monosodium phosphate (MSP). In Exp. 1, one thousand two hundred 1-d-old male broilers were used in a 42-d trial to assess the effect of ECP and iP supplementation on growth performance and nutrient digestibility. Dietary treatments were based on corn-soybean meal basal diets (BD) containing 239 and 221 g of CP, 8.2 and 6.6 g of Ca, and 2.4 and 1.5 g of nonphytate P (nPP) per kg for the starter and grower phases, respectively. Treatments consisted of the BD; the BD + 0.6, 1.2, or 1.8 g of iP from MSP per kg; and the BD + 250, 500, 750, or 1,000
phytase
units (FTU) of ECP per kg. Increasing levels of MSP improved gain, gain:feed, and tibia ash (linear, P < 0.01). Increasing levels of ECP improved gain, gain:feed, tibia ash (linear, P < 0.01), apparent ileal digestibility of P, N, Arg, His,
Phe
, and Trp at d 21 (linear, P < 0.05), and apparent retention of P at d 21 (linear, P < 0.05). Increasing levels of ECP decreased apparent retention of energy (linear, P < 0.01). Five hundred FTU of ECP per kg was determined to be equivalent to the addition of 0.72, 0.78, and 1.19 g of iP from MSP per kg in broiler diets based on gain, feed intake, and bone ash, respectively. In Exp. 2, forty-eight 10-kg pigs were used in a 28-d trial to assess the effect of ECP and iP supplementation on growth performance and nutrient digestibility. Dietary treatments consisted of a positive control containing 6.1 and 3.5 g of Ca and nPP, respectively, per kg; a negative control (NC) containing 4.8 and 1.7 g of Ca and nPP, respectively, per kg; the NC diet plus 0.4, 0.8, or 1.2 g of iP from MSP per kg; and the NC diet plus 500, 750, or 1,000 FTU of ECP per kg. Daily gain improved (linear, P < 0.05) with ECP addition, as did apparent digestibility of Ca and P (linear, P < 0.01). Five hundred FTU of ECP per kg was determined to be equivalent to the addition of 0.49 and 1.00 g of iP from MSP per kg in starter pigs diets, based on ADG and bone ash, respectively.
...
PMID:Efficacy and equivalency of an Escherichia coli-derived phytase for replacing inorganic phosphorus in the diets of broiler chickens and young pigs. 1709 29
Three experiments were conducted to evaluate the effect of supplementing
phytase
and xylanase on nutrient digestibility and performance of growing pigs fed wheat-based diets. In Exp. 1, 10 diets were fed to 60 pigs from 20 to 60 kg of BW to determine the effect of combining
phytase
and xylanase on apparent total tract digestibility (ATTD) of nutrients and growth performance. The 10 diets included a positive control diet (PC; 0.23% available P; 0.60% Ca) and a negative control diet (NC; 0.16% available P; 0.50% Ca) supplemented with
phytase
at 0, 250, and 500 fytase units (FTU)/kg and xylanase at 0, 2,000, and 4,000 xylanase units (XU)/kg in a 3 x 3 factorial arrangement. In Exp. 2, 6 ileally cannulated barrows (initial BW = 35.1 kg) were fed 4 wheat-based diets in a 4 x 4 Latin square design, with 2 added columns to determine the effect of combining
phytase
and xylanase on apparent ileal digestibility (AID) of nutrients. The 4 diets were NC (same as that used in Exp. 1) or NC supplemented with
phytase
at 500 FTU/kg, xylanase at 4,000 XU/kg, or
phytase
at 500 FTU/kg plus xylanase at 4,000 XU/kg. In Exp. 3, 36 barrows (initial BW = 55.5 kg) were fed 4 diets based on prepelleted (at 80 degrees C) and crumpled wheat for 2 wk to determine the effect of
phytase
supplementation on ATTD of nutrients. The 4 diets fed were a PC (0.22% available P; 0.54% Ca) and a NC (0.13% available P; 0.43% Ca) alone or with
phytase
at 500 or 1,000 FTU/kg. All diets in the 3 experiments contained Cr(2)O(3) as an indigestible marker. No synergistic interactions were detected between
phytase
and xylanase on any of the response criteria measured in Exp. 1 or 2. There were no dietary effects on growth performance in Exp. 1. In Exp. 1,
phytase
at 250 FTU/kg increased the ATTD of P and Ca by 51 and 11% at 20 kg of BW or by 54 and 10% at 60 kg of BW, respectively, but increasing the level of
phytase
to 500 FTU/kg only increased (P < 0.05) ATTD of P at 20 kg of BW. In Exp. 2,
phytase
at 500 FTU/kg increased (P < 0.05) the AID of P and Ca by 21 and 12%, respectively. In Exp. 3,
phytase
at 500 FTU/kg improved (P < 0.05) ATTD of P by 36%, but had no further effect at 1,000 FTU/kg. Xylanase at 4,000 XU/kg improved (P < 0.05) AID of Lys, Leu,
Phe
, Thr, Gly, and Ser in Exp. 2. In conclusion,
phytase
and xylanase improved P and AA digestibilities, respectively, but no interaction between the 2 enzymes was noted.
...
PMID:Nutrient digestibility and performance responses of growing pigs fed phytase- and xylanase-supplemented wheat-based diets. 1820 76
The effects of phytic acid and 2 sources of exogenous
phytase
(bacterial vs. fungal) on the flow of endogenous amino acids at the terminal ileum of broilers were assessed using the enzyme-hydrolyzed casein method. Phytic acid (as the sodium salt) was included in a purified diet at 8.5 and 14.5 g/kg, and each diet was fed without or with a fungal (Aspergillus niger-derived) or a bacterial (Escherichia coli-derived) microbial
phytase
at 500
phytase
units/kg of diet. Increasing the concentration of phytic acid in the diet from 8.5 to 14.5 g/kg increased (P < 0.001) the flow of all measured amino acids by an average of 68%, with a range from 17% for proline to 145% for
phenylalanine
. The flow of endogenous aspartic acid, serine, glutamic acid, glycine, leucine, tyrosine,
phenylalanine
, and histidine were increased by more than the mean, indicating changes in the composition of endogenous protein in response to the presence of higher concentrations of phytic acid. Supplementation of both phytases reduced (P < 0.001) the flow of endogenous amino acids, but the reduction (P = 0.06) was greater for the bacterial
phytase
compared with the fungal
phytase
. These data suggest that a substantial part of the amino acid and energy responses observed following
phytase
supplementation in broiler chickens stems from reduced endogenous amino acid flows and that the capacity of different phytases to counteract the antinutritive properties of phytic acid vary.
...
PMID:Influence of dietary phytic acid and source of microbial phytase on ileal endogenous amino acid flows in broiler chickens. 1893 Nov 80
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