Engineering crop plants: getting a handle on phosphate.

In plant seeds, most of the phosphate is in the form of phytic acid. Phytic acid is largely indigestible by monogastric animals and is the single most important factor hindering the uptake of a range of minerals. Engineering crop plants to produce a heterologous phytase improves phosphate bioavailability and reduces phytic acid excretion. This reduces the phosphate load on agricultural ecosystems and thereby alleviates eutrophication of the aquatic environment. Improved phosphate availability also reduces the need to add inorganic phosphate, a non-renewable resource. Iron and zinc uptake might be improved, which is significant for human nutrition in developing countries.

[1]  H. Bouis.  Improving human nutrition through agriculture. Based on the meeting on Improving Human Nutrition through Agriculture: the Role of International Agricultural Research, held at the International Rice Research Institute in Los Baños, Philippines, 5-7 October 1999. , 2000 .

[2]  Y. Han,et al.  Role of glycosylation in the functional expression of an Aspergillus niger phytase (phyA) in Pichia pastoris. , 1999, Archives of biochemistry and biophysics.

[3]  N. Mandal,et al.  Isolation, purification and characterization of phytase from germinating mung beans , 1972 .

[4]  L. Pasamontes,et al.  Gene cloning, purification, and characterization of a heat-stable phytase from the fungus Aspergillus fumigatus , 1997, Applied and environmental microbiology.

[5]  X. Wang,et al.  Differentially expressed forms of 1-L-myo-inositol-1-phosphate synthase (EC 5.5.1.4) in Phaseolus vulgaris. , 1996, Journal of Biological Chemistry.

[6]  Xiaohong Wang,et al.  Differentially Expressed Forms of 1-L-myo-Inositol-1-Phosphate Synthase (EC) in Phaseolus vulgaris* , 1996, The Journal of Biological Chemistry.

[7]  C. Rosell,et al.  Use of fungal phytase to improve breadmaking performance of whole wheat bread. , 2001, Journal of agricultural and food chemistry.

[8]  R. Simpson,et al.  The growth and phosphorus utilisation of plants in sterile media when supplied with inositol hexaphosphate, glucose 1-phosphate or inorganic phosphate , 2000, Plant and Soil.

[9]  G. Rimbach,et al.  Enhancement of zinc utilization from phytate-rich soy protein isolate by microbial phytase , 1993, Zeitschrift fur Ernahrungswissenschaft.

[10]  M. Cheryan.  Phytic acid interactions in food systems. , 1980, Critical reviews in food science and nutrition.

[11]  F. Asmar.  Variation in activity of root extracellular phytase between genotypes of barley , 1997, Plant and Soil.

[12]  V. Ravindran,et al.  Phytates: occurrence, bioavailability and implications in poultry nutrition , 1995 .

[13]  I. Sussex,et al.  1 L-myo-Inositol 1-Phosphate Synthase from Arabidopsis thaliana , 1995, Plant physiology.

[14]  R. Simpson,et al.  Phytase and acid phosphatase activities in extracts from roots of temperate pasture grass and legume seedlings , 1999 .

[15]  Bing-Lan Liu,et al.  The Induction and Characterization of Phytase and Beyond , 1998 .

[16]  J. J. Scott,et al.  Specificity of Hydrolysis of Phytic Acid by Alkaline Phytase from Lily Pollen , 1994, Plant physiology.

[17]  A. Kondo,et al.  A New Type of Phytase from Pollen of Typha latifolia L. , 1985 .

[18]  Cecil W. Forsberg,et al.  Pigs expressing salivary phytase produce low-phosphorus manure , 2001, Nature Biotechnology.

[19]  R. Beudeker,et al.  Phytase-containing Transgenic Seeds as a Novel Feed Additive for Improved Phosphorus Utilization , 1993, Bio/Technology.

[20]  F. Loewus,et al.  myo-Inositol metabolism in plants , 2000 .

[21]  E. Grabau,et al.  A novel phytase with sequence similarity to purple acid phosphatases is expressed in cotyledons of germinating soybean seedlings. , 2001, Plant physiology.

[22]  P. Perez,et al.  Structure of two maize phytase genes and their spatio-temporal expression during seedling development , 1999, Plant Molecular Biology.

[23]  P. Lucca,et al.  Genetic engineering approaches to improve the bioavailability and the level of iron in rice grains , 2001, Theoretical and Applied Genetics.

[24]  M. Johnson,et al.  The Arabidopsis thaliana myo-Inositol 1-Phosphate Synthase (EC 5.5.1.4) , 1994, Plant physiology.

[25]  F. Loewus,et al.  A Calcium-Activated Phytase from Pollen of Lilium longiflorum. , 1986, Plant physiology.

[26]  M. Tate,et al.  The phytases. II. Properties of phytase fractions F 1 and F 2 from wheat bran and the myoinositol phosphates produced by fraction F 2 . , 1973, Biochimica et biophysica acta.

[27]  M. Alminger,et al.  Identification and Properties of myo -Inositol Hexakisphosphate Phosphohydrolases (Phytases) from Barley (Hordeum vulgare)☆ , 2000 .

[28]  M. Osaki,et al.  Secretion of phytase from the roots of several plant species under phosphorus-deficient conditions , 1997, Plant and Soil.

[29]  V. Raboy,et al.  Genetics and breeding of seed phosphorus and phytic acid , 2001 .

[30]  W. Eeckhout,et al.  Total phosphorus, phytate-phosphorus and phytase activity in plant feedstuffs , 1994 .

[31]  A. H. Ullah,et al.  Characterization of recombinant fungal phytase (phyA) expressed in tobacco leaves. , 1999, Biochemical and biophysical research communications.

[32]  J. Gagnon,et al.  Purification and characterization of a phytase (myo-inositol-hexakisphosphate phosphohydrolase) accumulated in maize (Zea mays) seedlings during germination. , 1993, The Biochemical journal.

[33]  E. Beck,et al.  Maize Root Phytase (Purification, Characterization, and Localization of Enzyme Activity and Its Putative Substrate) , 1996, Plant physiology.

[34]  L. Stephens,et al.  Stepwise phosphorylation of myo-inositol leading to myo-inositol hexakisphosphate in Dictyostelium , 1990, Nature.

[35]  V. Raboy,et al.  Phytic acid and phosphorus in crop seeds and fruits: a global estimate , 2000, Seed Science Research.

[36]  F. Viteri,et al.  Effect of genetically modified, low-phytic acid maize on absorption of iron from tortillas. , 1998, The American journal of clinical nutrition.

[37]  J. A. Nelemans,et al.  The effect of phytase on the availability of P from myo-inositol hexaphosphate (phytate) for maize roots , 1993, Plant and Soil.

[38]  P. Umbeck,et al.  Soybeans transformed with a fungal phytase gene improve phosphorus availability for broilers. , 1998, Poultry science.

[39]  J. S. Radcliffe,et al.  Comparison of genetically engineered microbial and plant phytase for young broilers. , 2000, Poultry science.

[40]  S. Rasmussen,et al.  Generation of transgenic wheat (Triticum aestivum L.) for constitutive accumulation of an Aspergillus phytase , 2000, Molecular Breeding.

[41]  Clemens Broger,et al.  Crystal structure of phytase from Aspergillus ficuum at 2.5 Å resolution , 1997, Nature Structural Biology.

[42]  R. V. Etten,et al.  HUMAN PROSTATIC ACID PHOSPHATASE: A HISTIDINE PHOSPHATASE * , 1982, Annals of the New York Academy of Sciences.

[43]  J. Bewley,et al.  Subcellular distribution of phytin in the endosperm of developing castor bean: a possibility for its synthesis in the cytoplasm prior to deposition within protein bodies , 1984, Planta.

[44]  M. Wyss,et al.  Comparison of the Thermostability Properties of Three Acid Phosphatases from Molds: Aspergillus fumigatusPhytase, A. niger Phytase, and A. nigerpH 2.5 Acid Phosphatase , 1998, Applied and Environmental Microbiology.

[45]  E. Morris,et al.  Phytate: A good or a bad food component? , 1995 .

[46]  G. Gregorio,et al.  Breeding for Trace Mineral Density in Rice , 2000 .

[47]  M. Lehmann,et al.  The consensus concept for thermostability engineering of proteins. , 2000, Biochimica et biophysica acta.

[48]  Kunisuke Tanaka,et al.  Energy-dispersive x-ray analysis of phytin globoids in aleurone particles of developing rice grains , 1979 .

[49]  A. Richardson,et al.  Extracellular secretion of Aspergillus phytase from Arabidopsis roots enables plants to obtain phosphorus from phytate. , 2001, The Plant journal : for cell and molecular biology.

[50]  G. Irving,et al.  Inositol Phosphate Phosphatases of Microbiological Origin: the Inositol Pentaphosphate Products of Aspergillus ficuum Phytases , 1972, Journal of bacteriology.

[51]  V. Raboy,et al.  Linkage mapping of maize and barley myo-inositol 1-phosphate synthase DNA sequences: correspondence with a low phytic acid mutation , 1999, Theoretical and Applied Genetics.

[52]  S. Maugenest,et al.  Cloning and characterization of a cDNA encoding a maize seedling phytase. , 1997, The Biochemical journal.

[53]  R. Greiner,et al.  Purification and characterization of two phytases from Escherichia coli. , 1993, Archives of biochemistry and biophysics.

[54]  A. Richardson,et al.  Acid phosphomonoesterase and phytase activities of wheat (Triticum aestivum L.) roots and utilization of organic phosphorus substrates by seedlings grown in sterile culture , 2000 .

[55]  R. Berka,et al.  Molecular Characterization and Expression of a Phytase Gene from the Thermophilic Fungus Thermomyces lanuginosus , 1998, Applied and Environmental Microbiology.

[56]  J. Lott.  Accumulation of seed reserves of phosphorus and other minerals , 1984 .

[57]  T. Joh,et al.  The Pathway of Dephosphorylation of myo-Inositol Hexakisphosphate by Phytases from Wheat Bran of Triticum aestivum L. cv. Nourin #61 , 2000, Bioscience, biotechnology, and biochemistry.

[58]  V. Raboy,et al.  The timing and rate of phytic Acid accumulation in developing soybean seeds. , 1987, Plant physiology.

[59]  E. Grabau,et al.  Expression of D-myo-inositol-3-phosphate synthase in soybean. Implications for phytic acid biosynthesis. , 2001, Plant physiology.

[60]  R. Greiner,et al.  PURIFICATION AND PROPERTIES OF A PHYTASE FROM RYE , 1998 .

[61]  R. Greiner,et al.  PURIFICATION AND CHARACTERIZATION OF A PHYTASE FROM SPELT , 1994 .

[62]  R. Hanlon,et al.  Secretion of Active Recombinant Phytase from Soybean Cell-Suspension Cultures , 1997, Plant physiology.

[63]  O. Adeola.  Digestive utilization of minerals by weanling pigs fed copper- and phytase-supplemented diets , 1995 .

[64]  E. Chavez,et al.  The effects of supplemental microbial phytase on the performance and utilization of dietary calcium, phosphorus, copper, and zinc in broiler chickens fed corn-soybean diets. , 1996, Poultry science.

[65]  J. H. Wilson,et al.  Comparison of phytase from genetically engineered Aspergillus and canola in weanling pig diets. , 2000, Journal of animal science.

[66]  B. Phillippy,et al.  Expression of an Aspergillus niger Phytase (phyA) in Escherichia coli , 1997 .

[67]  M. Osaki,et al.  Purification and characterization of phytase induced in tomato roots under phosphorus-deficient conditions , 1997 .

[68]  A. H. Ullah,et al.  Immobilization of Aspergillus ficuum phytase: product characterization of the bioreactor. , 1988, Preparative biochemistry.

[69]  B. L. O’dell,et al.  Distribution of phytate and nutritionally important elements among the morphological components of cereal grains , 1972 .

[70]  S. Naito,et al.  Temporal and spatial patterns of accumulation of the transcript of Myo-inositol-1-phosphate synthase and phytin-containing particles during seed development in rice. , 1999, Plant physiology.

[71]  F. Loewus,et al.  Localization of constitutive phytases in lily pollen and properties of the pH 8 form , 1988 .

[72]  P. V. van Haastert,et al.  Nucleus-associated phosphorylation of Ins(1,4,5)P3 to InsP6 in Dictyostelium. , 1995, The Biochemical journal.

[73]  A. V. Ooyen,et al.  Stable Accumulation of Aspergillus niger Phytase in Transgenic Tobacco Leaves , 1995, Plant physiology.

[74]  A. H. Ullah,et al.  Purification and characterization of phytase from cotyledons of germinating soybean seeds. , 1988, Archives of biochemistry and biophysics.