磷酸酶

Based on the absorbance change of indicators with the concentration of hydrogen ion released from the enzyme-catalyzed reaction, a convenient colorimetry method is established for the assay of acidic phospholipase 〓 and glycogen phosphorylase b Brilliant yellow and bromothymol blue are chosen as indicators for assays of acidic phospholipase 〓 and glycogen phosphorylase b by following the absorbance changes at 495 nm and 615nm respectively The method is simple, sample-saving, sensitive and valid for a wide range of enzyme concentrations.

为了研究糖原磷酸化酶的激活动力学和酸性磷脂酶〓的复性过程，我们根据酶催化反应中释放氢离子浓度的变化引起相应的指示剂的光吸收发生变化的原理，建立了一种简捷的比色法，用于测定酸性磷脂酶〓和糖原磷酸化酶b的活性。选用亮黄和溴麝香草酚兰分别作为酸性磷脂酶〓和糖原磷酸化酶b测活的指示剂，在495 nm和615 nm处检测二者的光吸收值的变化，可以测定酶活。本方法的优点是，可在比较宽的酶浓度范围内进行活力测定，而且操作简单、节省样品、灵敏度高。

However, the first one enzyme 1-deoxy-D-xylulose 5-phosphate synthase gene and the second one enzyme 1-deoxy-D-xylulose 5-phosphate reductoisomerase gene in MEP pathway had been reported and expressed in the latex of rubber tree, indicating that MEP pathway may be involved in rubber biosynthesis.4 - hydroxy -3 - methyl -2 -- butenyl -4 - phosphate reductaseis the last enzyme that catalytic 4 - hydroxy -3 - methyl -(2E)- butenyl -4 - phosphate to generate isopentenyl pyrophosphate.

然而已有报道MEP途径中第1个酶1-脱氧-D-木酮糖-5-磷酸合成酶（1-deoxy-D-xylulose 5-phosphate synthase，DXS）基因和第2个酶1-脱氧-D-木酮糖-5-磷酸还原酶（1-deoxy-D-xylulose 5-phosphate reductoisomerase ，DXR）基因在橡胶树胶乳中的表达，这表明MEP途径可能参与橡胶的生物合成。4-羟基-3-甲基-2--丁烯基-4-磷酸还原酶（4-hydroxy -3-methyl-2--butenyl-4-diphosphate reductase，HDR）是异戊烯基焦磷酸合成途径之一甲基赤藓糖磷酸（methylerythritol phosphate，MEP）途径中的最后一个酶，催化4-羟基-3-甲基-(2E)-丁烯基-4-磷酸生成异戊烯基焦磷酸。

Glioma is still one of refractory disease in the neurosurgical field; the development of new primary and adjuvant treatment is vital. Recently, the gene therapy of glioma is developed rapidly and there are many methods about the gene therapy that include: suicide gene therapy, immunologic gene therapy, drug resistangce gene therapy, angiostatin gene therapy and so on. The sucide gene therapy is the most potential approach of antitumer, these nonmammalian genes encode enzyme that convert nontoxic prodrugs into highly toxic metablites. Cells transfected with suicide genes are targeted for specific negative selection, witch can be induced by administrtion of the corresponding produg. Among the enzyme/produg combinations, two of the best characterized system are herpes simplex virus thymidine kinase /ganciclovir and Escherichia coli cytosine deaminase /5-flourocytosine (5-FC). The formor can convert the antiviral nucleoside analogs acyclovir , ganciclovir to their nucleoside monophosphate derivatives, the monophosphate forms are subsequently phosphorylated by endogenus cellular kinases to triphosphates, these molecules are potent inhibitors of DNA synthesis.

近年来脑胶质瘤的基因治疗发展迅速，应运而生的方法有自杀基因、免疫基因、多药耐药基因以及抗血管生成基因等，其中自杀基因被认为是最有前景的基因治疗方法，它又称病毒介导的酶／药物前体疗法，是利用转基因技术将哺乳动物细胞中所不含有的自杀基因转入到哺乳动物肿瘤细胞中，该基因表达的产物可将无毒的药物前体转化为毒性药物，从而选择性杀伤该肿瘤细胞，常用的自杀基因有单纯疱疹病毒-胸苷激酶基因和大肠杆菌胞嘧啶脱氨酶基因，前者催化无毒性抗病毒核苷类似物如丙氧鸟苷、无环鸟苷等成为单磷酸核苷衍生物，然后在内源性细胞激酶作用下转化为具有明显毒性的三磷酸核苷，作为DNA合成链的终止剂和DNA合成酶的抑制剂，干扰细胞DNA的合成；后者编码的胞嘧啶脱氨酶可催化5-氟胞嘧啶（5-FC）脱氨成为5-氟尿嘧啶（5-FU），然后代谢为有毒性的5-氟尿嘧啶-5′三磷酸（5-FUTP）和5-氟-2′脱氧尿嘧啶-5′磷酸（5-FdUTP），5-FUTP通过与UTP竞争性结合而抑制mRNA和tRNA的合成，5-FdUTP则作用于胸苷合成酶，导致TMP衰竭而阻止DNA的合成，最终诱导肿瘤细胞凋亡。

Escherichia coli and many other microoganism synthesize aromatic amino acids through the condensation reaction between phospho enolpyruvate and erythro.

ppsA和tktA是芳香族氨基酸生物合成中心途径的两个关键酶基因，在大肠杆菌中，ppsA基因编码磷酸烯醇式丙酮酸合成酶A ，该酶催化丙酮酸合成磷酸烯醇式丙酮酸；tktA基因编码转酮酶A ，该酶在磷酸戊糖途径中生成 4 磷酸赤藓糖起主要作用。

The results showed that VAM increaced soil acid and alkaline phosphatase activity in the rhizosphere. The effect of G. margarita was the biggest.

结果表明，接种菌根真菌增加了根际土壤酸性和碱性磷酸酶活性，Gigasporamargarita菌根菌的作用大于其它两个菌根菌。

Inwheat intercropped with soybean not only N situation could be improved butalso P situation could be.2In intercropping,the pH of soybean rhizospherewas decreased by increasing the R-Apase activity,which could decelerate thetransforming and fixing P fertilizer.3In both monoculture and intercroppingsystem,the soil pH of rhizosphere was affected by cropping system at two Plevel which only 0.1-4mm distance from the root surface,but the effect of S-Apase activity in the rhizospher soil by cropping system was less than3mm.In effect,the rhizosphere P was really available nutrient,and applyingP to rhizosphere was effective ways to reduce the P nutrient competition.4Inwheat/soybean intercropping,the peak stage of reduction ability of roots wasthe same as that of the root growth,so that the time compensation appearedin intensity of nutrient absorption.

间套作大豆、小麦、玉米根系Apase的差异又反映出大豆利用土壤磷的潜在能力最大，而玉米最小，可见禾谷类的小麦与大豆间套后不但能改善小麦的氮素营养状况还使磷素营养也得以好转。2）间套大豆根际pH值的下降，导致磷肥施入土壤后形成〓-P的比例显著提高，转化成〓-P等难溶性磷减少，说明间套的大豆能减缓肥料磷在土壤中的转化和固定，减少磷素向无效化方向转化。3）复合群体根际土壤pH值的影响一般只发生在0.1-4mm的根际微区，而土壤磷酸酶的影响供磷与否在距根表3mm以外都无多大差异，说明根际磷才是真正有效磷，根际施磷是解决磷素竞争的有效途径。4）。

A typical area of habitat fragmentation in the Thousand-Island Lake, Zhejiang Province, was selected as subject to study effects of habitat variation as a result of island forming, on arbuscular mycorrhizae infection rate and its correlation with phosphatase activity in the rhizosphere of Castanopsis sclerophylla.

以浙江千岛湖典型生境片断化区域苦槠为材料，研究了水库形成后岛屿化导致的群落生境差异对苦槠AM侵染率的影响以及AM侵染率与根际土壤磷酸酶活性的相关性。

The acid phosphetase in the blood cells of oncomelania hupensis was observed at the light microscope level by the burstone stained technique.

将解剖的钉螺软体组织经挤压法获取钉螺血淋巴液，以偶氮色素法染色后，光学显微镜下观察螺血淋巴细胞酸性磷酸酶活性。

Methods Primary brown adipocytes from rat fetuses, and from wild-type neonate mice and neonate mice deficient in the gene encoding protein tyrosine phosphatase-1B (Ptpn1, also known as Ptp1b) were cultured in the absence or presence of TNFα and different nuclear receptor agonists.

原代棕色脂肪细胞自大鼠胚胎、野生型新生小鼠和蛋白酪氨酸磷酸酶-1B基因基因(Ptpn1，也被称作 Ptp1b)缺陷新生小鼠，在加或者不加TNFα和不同浓度核受体激动剂中培养。

Mol. Cell. Biol. 19:7491 7500.[2].Bassett,C.A.,Pawluk,R.J.,and Pilla,A.A.(1974)Augmentation of bone repair by inductively coupled electromagnetic fields. Science 184,575-577[3]. Scott, G., and King, J.

脉冲电磁场促进骨髓间充质干细胞碱性磷酸酶的表达以及成骨指标如 osteotrix ，骨型态蛋白4和 I 型胶原的表达。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。