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Serum alkaline phosphatase activity was determined in 290 Norwegian goats, from 8 months to 10 years of age. The investigations revealed a wide range of individual enzyme activities which constituted two distinct peaks with mean values of 2.37 ± 1.42 and 37.73 ± 14.78 “Sigma” units per ml respectively. Forty-one of the 290 goats were examined by 15 successive samplings for 18 months without obtaining lapping-over values between the two groups. The segregation of the high enzyme level indicated a genetic dominant inheritance.  相似文献   

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Genetic Analysis of Regulatory Mutants of Alkaline Phosphatase of E. COLI   总被引:16,自引:0,他引:16  
A fine structure map of the phoR region of E. coli , mutations of which affect the rate of alkaline phosphatase synthesis, was constructed by Hfr x F- crosses. Mutations causing three different phenotypes (previously reported as phoRa, phoRb, phoRc (Garen and Echols 1962a, b)) are clustered in three closely linked genetic loci. PhoR mutants of all three types, including the phoRb type not previously tested, are recessive to wild-type phoR+. In addition, phoRa and phoRc complement each other, while phoRa and phoRb do not. Our results support the hypothesis of Morris et al. (1974) that phoRc mutants represent a cistron (phoB) different from phoR.  相似文献   

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铅对鲫鱼碱性磷酸酶和酸性磷酸酶活性的影响   总被引:3,自引:0,他引:3  
高举  赵欣平  詹付凤  程凯 《四川动物》2008,27(2):201-204
在实验条件下,将鲫鱼置于1、10、40 mg/L的Pb2 溶液中静态染毒,分别在24 h、48 h、96 h、144 h测定鳃、肝、胰、肾、脑组织的碱性磷酸酶(AKP)和酸性磷酸酶(ACP)活性.结果 表明,鲫鱼鳃、肝、胰、肾、脑组织中碱性磷酸酶和酸性磷酸酶的活性随着铅浓度的升高和染毒时间的延长均呈下降趋势,其中以肾脏和脑下降最明显.  相似文献   

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Among 569 schoolchildren (386 boys and 183 girls) aged 14-17 years, 233 had serum alkaline phosphatase values of 30 K.A. units or greater. There was no significant difference in the results in Asian, white, or West Indian children. The mean values were significantly greater in boys than girls and both showed a fall in mean values with increasing age. Radiological rickets occurred in at least 4% of the survey, and was more common in Asians. Low calcium and high hydroxyproline excretion in most of those investigated and the response to vitamin D therapy suggests that most children with alkaline phosphatase levels above 30 K.A. units have rickets.Since the decline of the widespread supplementation of the diet with vitamin D, the demands of the physiological growth spurt for extra vitamin D in adolescents already on a borderline intake may be responsible for the great increase in “biochemical” rickets. Once the growth spurt is over the condition subsides but the results of impaired growth or permanent pelvic deformity will not necessarily be eradicated.  相似文献   

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The conserved active site of alkaline phosphatases (AP) contains catalytically important Zn2+ (M1 and M2) and Mg2+-sites (M3) and a fourth peripheral Ca2+ site (M4) of unknown significance. We have studied Ca2+ binding to M1-4 of tissue-nonspecific AP (TNAP), an enzyme crucial for skeletal mineralization, using recombinant TNAP and a series of M4 mutants. Ca2+ could substitute for Mg2+ at M3, with maximal activity for Ca2+/Zn2+-TNAP around 40% that of Mg2+/Zn2+-TNAP at pH 9.8 and 7.4. At pH 7.4, allosteric TNAP-activation at M3 by Ca2+ occurred faster than by Mg2+. Several TNAP M4 mutations eradicated TNAP activity, while others mildly influenced the affinity of Ca2+ and Mg2+ for M3 similarly, excluding a catalytic role for Ca2+ in the TNAP M4 site. At pH 9.8, Ca2+ competed with soluble Zn2+ for binding to M1 and M2 up to 1 mM and at higher concentrations, it even displaced M1- and M2-bound Zn2+, forming Ca2+/Ca2+-TNAP with a catalytic activity only 4–6% that of Mg2+/Zn2+-TNAP. At pH 7.4, competition with Zn2+ and its displacement from M1 and M2 required >10-fold higher Ca2+ concentrations, to generate weakly active Ca2+/Ca2+-TNAP. Thus, in a Ca2+-rich environment, such as during skeletal mineralization at pH 7.4, Ca2+ adequately activates Zn2+-TNAP at M3, but very high Ca2+ concentrations compete with available Zn2+ for binding to M1 and M2 and ultimately displace Zn2+ from the active site, virtually inactivating TNAP. Those ALPL mutations that substitute critical TNAP amino acids involved in coordinating Ca2+ to M4 cause hypophosphatasia because of their 3D-structural impact, but M4-bound Ca2+ is catalytically inactive. In conclusion, during skeletal mineralization, the building Ca2+ gradient first activates TNAP, but gradually inactivates it at high Ca2+ concentrations, toward completion of mineralization.  相似文献   

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Phosphatase enzymes are responsible for much of the recycling of organic phosphorus in soils. The PhoD alkaline phosphatase takes part in this process by hydrolyzing a range of organic phosphoesters. We analyzed the taxonomic and environmental distribution of phoD genes using whole-genome and metagenome databases. phoD alkaline phosphatase was found to be spread across 20 bacterial phyla and was ubiquitous in the environment, with the greatest abundance in soil. To study the great diversity of phoD, we developed a new set of primers which targets phoD genes in soil. The primer set was validated by 454 sequencing of six soils collected from two continents with different climates and soil properties and was compared to previously published primers. Up to 685 different phoD operational taxonomic units were found in each soil, which was 7 times higher than with previously published primers. The new primers amplified sequences belonging to 13 phyla, including 71 families. The most prevalent phoD genes identified in these soils were affiliated with the orders Actinomycetales (13 to 35%), Bacillales (1 to 29%), Gloeobacterales (1 to 18%), Rhizobiales (18 to 27%), and Pseudomonadales (0 to 22%). The primers also amplified phoD genes from additional orders, including Burkholderiales, Caulobacterales, Deinococcales, Planctomycetales, and Xanthomonadales, which represented the major differences in phoD composition between samples, highlighting the singularity of each community. Additionally, the phoD bacterial community structure was strongly related to soil pH, which varied between 4.2 and 6.8. These primers reveal the diversity of phoD in soil and represent a valuable tool for the study of phoD alkaline phosphatase in environmental samples.  相似文献   

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 <正> 胎盘型碱性磷酸酶(P-ALP)是碱性磷酸酶(EC3.1.3.1.ALP)的一种同工酶。P-ALP除出现于妊娠妇女血清外,一些学者还从恶性肿瘤患者血清中发现此酶,并证明它是一种特异性较强的肿瘤标志物。据此,建立P-ALP的简易纯化方法,制备纯度较高的酶制品是建立P-ALP灵敏的微量检测法的先决条件。本文报道以L-苯丙氨酸(L-phe)为配基,用氯代环氧丙烷活化Sepharose 4B的亲和层析法,从人胎盘纯化P-ALP,并对其部分性质进行了研究。  相似文献   

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Renal hyperfiltration, which is associated with renal injury, occurs in diabetic or obese individuals. Serum alkaline phosphatase (ALP) level is also elevated in patients with diabetes (DM) or metabolic syndrome (MS), and increased urinary excretion of ALP has been demonstrated in patients who have hyperfiltration and tubular damage. However, little was investigated about the association between hyperfiltration and serum ALP level. A retrospective observational study of the 21,308 adults in the Korea National Health and Nutrition Examination Survey IV-V databases (2008–2011) was performed. Renal hyperfiltration was defined as exceeding the age- and sex-specific 97.5th percentile. We divided participants into 4 groups according to their estimated glomerular filtration rate (eGFR): >120, 90–119, 60–89, and <60 mL/min/1.73 m2. The participants with eGFR >120 mL/min/1.73 m2 showed the highest risk for MS, in the highest ALP quartiles (3.848, 95% CI, 1.876–7.892), compared to the lowest quartile. Similarly, the highest risk for DM, in the highest ALP quartiles, was observed in participants with eGFR >120 ml/min/1.73 m2 (2.166, 95% CI, 1.084–4.329). ALP quartiles were significantly associated with albuminuria in participants with eGFR ≥ 60 ml/min/1.73m2. The highest ALP quartile had a 1.631-fold risk elevation for albuminuria with adjustment of age and sex. (95% CI, 1.158-2.297, P = 0.005). After adjustment, the highest ALP quartile had a 1.624-fold risk elevation, for renal hyperfiltration (95% CI, 1.204–2.192, P = 0.002). In addition, hyperfiltration was significantly associated with hemoglobin, triglyceride, white blood cell count, DM, smoking, and alcohol consumption (P<0.05). The relationship between serum ALP and metabolic disorders is stronger in participants with an upper-normal range of eGFR. Higher ALP levels are significantly associated with renal hyperfiltration in Korean general population.  相似文献   

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The seasonality of blood cholesterol is still not well established. Some have described a seasonal pattern with highest levels during autumn and lowest in summer, whereas others have reported no change. A number of studies showed circannual variations with maximum levels in winter and minimum in summer. The aim of this study was to examine the circannual variation of cholesterol in a large cohort in Israel. In the Israeli CORDIS study, employees of 21 factories were screened for cardiovascular disease risk factors during 1985-7. As part of the information gathered, serum cholesterol and blood counts were available for 3,726 men and 1,514 women. Serum cholesterol levels fit a circannual rhythm assessed by the cosinor analysis. Highest levels of serum cholesterol were found in spring and lowest in summer. We conclude that there is a circannual change of serum cholesterol, which could be partially associated with changes in environmental temperature. The circannual variation in serum cholesterol was considerable and should be taken into account when carrying out clinical evaluation of patients.  相似文献   

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Alkaline Phosphatase Subunits and Their Dimerization In Vivo   总被引:5,自引:8,他引:5       下载免费PDF全文
A pool of alkaline phosphatase subunits has been found in cells of Escherichia coli which are actively synthesizing the enzyme. The radioactive subunits from pulse-labeled cells were specifically recognized by their capacity to produce, upon incubation with Zn(++) and nonradioactive monomers, radioactive dimers with the characteristics of alkaline phosphatase. The pool of subunits was larger (10 times or more) than the amount expected to be bound to ribosomes and was bound to a rapidly sedimentable fraction from which 60% was released by ribonuclease. In a culture pulse-labeled for one-third (8 sec) of the enzyme synthetic time, the pool of radioactive monomers was 81% of the radioactive enzyme and was totally (98%) in the endoplasm. The size of the pool was increased by decreasing the dimerization rate without affecting protein synthesis. This was achieved by decreasing Zn(++) in the growth medium. It was found that the cells contained a full complement of monomers, although the level of active enzyme was low. A process subsequent to the release of the monomers from the ribosomes was found to be limiting the formation of the finished enzyme. This process affects the level of the pool of monomers independently from their synthesis.  相似文献   

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In wild-type Neurospora, alkaline phosphatase is made under conditions of phosphate limitation, but not conditions of phosphate sufficiency. Mutants at two unlinked loci, nuc-1 and nuc-2, do not make alkaline phosphatase under any conditions, while mutants at two quite closely linked loci, pcon and preg, make alkaline phosphatase even under conditions of phosphate sufficiency. pcon is extremely closely linked to nuc-2. nuc-2 and preg(c) (constitutive) mutants are recessive to their wild-type alleles in partial diploids as well as in heterokaryons, while pcon(c) mutants are dominant or co-dominant. nuc-1 is epistatic to both pcon(c) and preg(c) mutants. The implications of these findings for theories of metabolic control in eukaryotes are briefly discussed.  相似文献   

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Tham SC  Lim SH  Yeoh HH 《Biotechnology letters》2005,27(23-24):1865-1868
An acid phosphatase, free of deoxyribonuclease activity, was isolated from Manihot glaziovii leaves. It had a Mr of 78 kDa and was optimally active at pH 4.3 and 52 degrees C. It was inactivated at 65 degrees C over 15 min. It had a broad substrate specificity with strongest activity towards p-nitrophenyl phosphate. The enzyme dephosphorylated linearized pUC18 DNA and preventing self-ligation under the same conditions used for calf intestine alkaline phosphatase.  相似文献   

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SEVERAL recent studies suggest that at least part of the effect of vitamin D on intestinal calcium transport may be mediated by a calcium-stimulated ATPase (Ca ATPase) situated in the brush borders of intestinal mucosal cells1. Intestinal brush borders are known to contain several other enzymes which may be involved in digestion and transport, but the relationship between them is poorly understood2. In the case of the disaccharidases, the question of the number of enzymes responsible for the various activities has been raised3. Alkaline phosphatase is also present in brush borders but its function is unknown. During studies of the effect of various agents On intestinal calcium transport we noted a close correlation between the activities of alkaline phosphatase and Ca ATPase. We therefore wondered whether the activities might be due to a single enzyme species. Haussler et al.4 and Norman et al.5 have also noted a close relationship between the two activities under a variety of conditions but Holdsworth6 thinks the two activities are not related. We report here further evidence, based on denaturation by heat and on various dietary manipulations in the rat, which suggest that the two enzymes may be part of a single enzyme complex.  相似文献   

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研究组织特异性酶在胚胎发育中的表达图式对于研究细胞、组织和器官的分化具有重要意义。本文以 BCIP为底物研究了碱性磷酸酶在文昌鱼胚胎和幼体中的表达图式。在囊胚、原肠胚和神经胚早期(12~13小时)未检测到碱性磷酸酶的特异性表达;到神经胚中期(15小时,约6个体节),碱性磷酸酶在胚胎每一体节的中部开始表达,在胚胎中形成3~6个条纹(Fig.1);在18小时神经胚(9~10体节)中,碱性磷酸酶在肌节中表达(Fig.2);到24小时在后部内胚层中也开始表达(Fig.3);在36~48小时幼体中,碱性磷酸酶在消化道中强烈表达,但在咽鳃区不表达,同时在肌节中仍有弱的表达(Fig.4)。研究表明碱性磷酸酶可能在肌节的发育过程中具有一定作用。碱性磷酸酶在消化道中的表达可能与这一时期消化道开始行使功能有关。另外,L-苯丙氨酸只抑制36、48小时文昌鱼肠碱性磷酸酶活性,不抑制其体节肠碱性磷酸酶活性(Fig.5)、表明文昌鱼至少存在两种碱性磷酸酶:在消化道中表达的是一种肠型的,与脊椎动物碱性磷酸酶可能为同一类型;另一种主要在肌节中表达,可能是组织非特异性的破性磷酸酶。以上结果说明文昌鱼早期发育中碱性磷酸酶的表达与脊椎动物相似,具  相似文献   

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本研究利用石蜡切片结合组织化学方法研究奥尼罗非鱼(Oreochromis niloticus♀×O. aureus♂)消化道内非特异性酯酶、酸性磷酸酶和碱性磷酸酶的分布特点。结果发现,非特异性酯酶大量密集分布在前肠,其次为胃、食管和中肠,极少数零散分布在后肠。酸性磷酸酶主要分布于奥尼罗非鱼前肠,其次为中肠和胃,极少数分布在食管和后肠。碱性磷酸酶大量密集分布在奥尼罗非鱼前肠和中肠,其次为胃、食管和后肠。结果表明,奥尼罗非鱼前肠、中肠、食管和胃有较强的吸收和消化脂质功能,前肠、中肠和胃是蛋白质吸收和消化的主要部位,前肠和中肠是营养物质吸收的主要部位。  相似文献   

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