Structure of a cereal purple acid phytase provides new insights to phytate degradation in plants.
Structure of a cereal purple acid phytase provides new insights to phytate degradation in plants.
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DOI：
10.1016/j.xplc.2022.100305
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发表时间：
2022-03-14
影响因子：
10.5
通讯作者：
Hemmings, Andrew M.
中科院分区：
文献类型：
--
作者：
Faba-Rodriguez, Raquel;Gu, Yinghong;Salmon, Melissa;Dionisio, Giuseppe;Brinch-Pedersen, Henrik;Brearley, Charles A.;Hemmings, Andrew M.
谷物植酸盐是肌醇六磷酸的混合金属离子盐，占植物体内磷贮量的60%~ 80%，是包括人类在内的非反刍动物的有效抗营养素。通过紫色酸性植酸酶（PAPhy）的新功能化，一些谷物如小麦和黑麦获得了特别高的成熟谷物植酸酶活性。由于PAPhy活性提供磷酸盐，释放出苗所需的金属离子，并消除植酸盐的抗营养作用，因此其操纵和控制是目标作物性状。在这里，我们显示了发芽过程中诱导的小麦PAPhy的b2亚型的X射线晶体结构。这种高分辨率的晶体结构表明，植酸识别的模型，通过分子动力学模拟验证，牵连的两个序列插入（称为PAPhy基序）相对于一个典型的金属磷酸酯酶（MPE）域的元素在形成植酸特异性底物特异性口袋。这些基序在来自单子叶植物谷物的PAPhys中很好地保守，所述酶的特征在于对肌醇六磷酸的高特异性。通过诱变测试，发现PAPhy基序4中的残基His 229和MPE结构域中的残基Lys 410（两者都在PAPhys中保守）强烈影响植酸酶活性。这些结果解释了所观察到的谷物PAPhys的植酸酶活性，并为植物中植酸酶活性的合理工程化开辟了道路。谷物植酸盐占植物体内磷贮量的60%-80%，是一种有效的抗营养素。小麦紫酸性植酸酶的高分辨率X射线晶体结构鉴定了形成底物识别和水解所需的植酸特异性口袋的氨基酸序列基序。这种结构数据解释了观察到的这类酶的植酸酶活性，并开辟了在植物中植酸酶活性的合理工程的道路。
Grain phytate, a mixed metal ion salt of inositol hexakisphosphate, accounts for 60%–80% of stored phosphorus in plants and is a potent antinutrient of non-ruminant animals including humans. Through neofunctionalization of purple acid phytases (PAPhy), some cereals such as wheat and rye have acquired particularly high mature grain phytase activity. As PAPhy activity supplies phosphate, liberates metal ions necessary for seedling emergence, and obviates antinutrient effects of phytate, its manipulation and control are targeted crop traits. Here we show the X-ray crystal structure of the b2 isoform of wheat PAPhy induced during germination. This high-resolution crystal structure suggests a model for phytate recognition that, validated by molecular dynamics simulations, implicates elements of two sequence inserts (termed PAPhy motifs) relative to a canonical metallophosphoesterase (MPE) domain in forming phytate-specific substrate specificity pockets. These motifs are well conserved in PAPhys from monocot cereals, enzymes which are characterized by high specificity for phytate. Tested by mutagenesis, residues His229 in PAPhy motif 4 and Lys410 in the MPE domain, both conserved in PAPhys, are found to strongly influence phytase activity. These results explain the observed phytase activity of cereal PAPhys and open the way to the rational engineering of phytase activity in planta. Grain phytate accounts for 60%–80% of stored phosphorus in plants and is a potent antinutrient. The high-resolution X-ray crystal structure of a wheat purple acid phytase identifies amino acid sequence motifs forming phytate-specific specificity pockets necessary for substrate recognition and hydrolysis. This structural data explains the observed phytase activity of this class of enzymes and opens the way to the rational engineering of phytase activity in planta.
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影响因子：
5.5
作者：
Hess, Berk;Kutzner, Carsten;Lindahl, Erik
通讯作者：
Lindahl, Erik
DOI：
10.1107/s0907444909052925
发表时间：
2010-02
期刊：
Acta crystallographica. Section D, Biological crystallography
影响因子：
--
作者：
Adams PD;Afonine PV;Bunkóczi G;Chen VB;Davis IW;Echols N;Headd JJ;Hung LW;Kapral GJ;Grosse-Kunstleve RW;McCoy AJ;Moriarty NW;Oeffner R;Read RJ;Richardson DC;Richardson JS;Terwilliger TC;Zwart PH
通讯作者：
Zwart PH
影响因子：
10.7
作者：
Kumar, Sudhir;Stecher, Glen;Tamura, Koichiro
通讯作者：
Tamura, Koichiro
DOI：
10.1016/j.jchromb.2009.11.046
发表时间：
2010-02-01
影响因子：
3
作者：
Blaabjerg, K.;Hansen-Moller, J.;Poulsen, H. D.
通讯作者：
Poulsen, H. D.
影响因子：
3
作者：
Arturo Rivera-Solis, Rodrigo;Peraza-Echeverria, Santy;Aurora Herrera-Valencia, Virginia
通讯作者：
Aurora Herrera-Valencia, Virginia