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L. E. M. Niers J. A. M. Smeitink J. M. F. Trijbels R. C. A. Sengers A. J. M. Janssen L. P. van den Heuvel 《黑龙江环境通报》2001,21(10):871-880
NADH:ubiquinone oxidoreductase (complex I of the mitochondrial respiratory chain) deficiency is a severe disorder with an often early fatal outcome. Prenatal diagnosis for complex I defects currently relies mainly on biochemical assays of complex I in fetal tissues such as chorionic villi (CV), and is only in a minority of cases possible by means of mutational analysis of nuclear-encoded genes of complex I. We report on our experience to date with prenatal diagnosis in pregnancies at risk for complex I deficiency. We measured complex I activity in native CV and/or cultured CV in 23 pregnancies in 15 families. In accordance with the results of the investigations in CV, 15 children were born clinically unaffected. Two prenatally diagnosed unaffected fetuses and two prenatally diagnosed affected fetuses were lost prematurely with spontaneous or provoked abortions, respectively. Two affected children were born (prenatally found to be affected). In two pregnancies a discrepancy between native and cultured cells was found. We conclude that prenatal diagnosis for complex I deficiency can be reliably performed. Pitfalls were encountered in using cultured CV as a result of maternal cell contamination (MCC). Future research on pathogenic nuclear mutations underlying complex I deficiency will extend the possibilities for prenatal diagnosis at the molecular level. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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复合垂直流人工湿地基质氧化还原酶活性研究 总被引:1,自引:0,他引:1
对复合垂直流人工湿地系统(IVCW)基质中5种常见的氧化还原酶活性进行了研究.结果表明,氧化还原酶活性存在显著性季节差异,过氧化物酶在春、夏、秋三季的酶活性显著高于冬季的酶活性(P<0.05);多酚氧化酶和过氧化氢酶的活性最高在秋季;脱氢酶在夏、冬两季时酶活性显著高于秋季和春季的酶活性(P<0.05);硝酸盐还原酶在春、冬季时显著高于夏、秋季(P<0.01).空间分布上,除过氧化物酶外,湿地下行流池的酶活性显著高于上行流池,并且随着基质深度的增加递减;但基质硝酸盐还原酶各层之间差异不显著.图6表3参17 相似文献
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硝化作用微生物的分子生物学研究进展 总被引:30,自引:1,他引:30
回顾了硝化作用微生物的分子生物学研究进展 ,主要介绍了硝化作用微生物的种类 ,包括氨氧化菌、亚硝酸氧化菌、异养氨氧化菌和厌氧氨氧化菌 .这些微生物的系统发育分析表明亚硝化菌的系统发育相对简单 ,而硝化细菌则要复杂许多 .还介绍了在硝化作用微生物生态学研究中应用的分子生物学技术 ,如PCR、变性梯度胶电泳 (DGGE)、原位荧光杂交 (FISH)等 ,以及不同类群细菌中与硝化作用相关的酶类及其基因 .文章的最后还提出了一些研究展望 .图 3参 35 相似文献
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污水生物脱氮过程中N_2O的产生与活性污泥中细菌的羟氨氧化还原酶(Hydroxylamine oxidoreductase,HAO)活性有着密切关系.但目前活性污泥中细菌的HAO提取和活性测定方法尚未建立.本文首先探索了在25℃、酶活性反应液电子受体供体配比1∶1和终止剂选用2 mol·L~(-1)HCl条件下超声或高压破碎细胞法对HAO粗酶活性的影响,结果表明高压破碎比超声破碎获取的粗酶活性高(p0.01).在此基础上,我们进一步优化了高压破碎下压力大小、破碎次数和裂解液用量的参数.粗酶提取液中DNA含量、酶活力及酶比活力结果进行多因素方差分析表明压力大小(50、110或160 MPa)、破碎次数(1、2或3次)和裂解液用量(2、5或10 m L)均对脱氮活性污泥破碎效果、酶活性和比活力有显著影响(p0.01);综合DNA含量、酶活力及酶比活力结果看,110 MPa压力条件下,加5 m L裂解液破碎2次更适合污水生物处理中HAO的提取和活性测定,既节省时间,又能较好的保持酶活性. 相似文献
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锌污染对猪粪堆肥过程中氧化还原类酶活性的影响 总被引:1,自引:1,他引:0
以猪粪和秸秆为主要试验材料,添加不同浓度重金属Zn,采取发酵罐处理方法,在好氧高温条件下,研究了重金属锌污染对猪粪堆肥过程中多酚氧化酶、脱氢酶活性的影响,以及对堆腐过程堆体温度、堆料pH值、胡敏酸E4/E6值的影响.结果表明:①CK以及低量重金属Zn污染的堆料升温快,高温期持续时间长,达到无害化处理.②Zn含量为600mg·kg-1和900mg·kg-1的堆料E4/E6平均值小,有利于腐殖质的缩合和芳构化.③Zn含量为600mg·kg-1的堆料多酚氧化酶平均活性、脱氢酶平均活性最高,有助于堆料中木质素的降解及其产物的转化、微生物生长繁殖.④Zn含量为300mg·kg-1、600mg·kg-1、900mg·kg-1的堆料对pH有较强的控制能力,其脱氢酶活性均表现出一定的不稳定性,可能是重金属对脱氢酶活性有抑制作用的同时发生"抗性酶活性现象". 相似文献
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Anaerobic ammonium oxidation (Anammox) has become a promising method for biological nitrogen removal. However, this biotechnology application is always limited due to the low growth rate and biomass yield of Anammox bacteria. This study investigated the process of fast reactivation of an Anammox consortium idled for 2 years uia hydrodynamic stress control. The results showed that the Anammox system was efficiently and quickly reactivated by shortening of the hydraulic retention time (I-IRT) of the reactor from 12 to 6 hr within 68 days of operation. Moreover, at a 4-hr HRT with an influent total nitrogen loading rate of 1.2 kg N/(m3.day), the reactor maintained high biological performance with an ammonium removal loading rate of 0.52 kg N/(m3.day) and a nitrite removal rate of 0.59 kg N/(m3.day). In the reactivated Anammox reaction, the stoichiometric coefficients of NH4-N to NOE-N and NH4-N to NO4-N were 1:1.04± 0.08 and 1:0.31 ± 0.03, respectively. The specific Anammox activity and hydrazine oxidoreductase activity, both of which represent the degree of Anammox bacteria present, increased as the hydrodynamic stress increased and were maximally (125.38 ± 3.01 mg N/(g VSS.day) and 339.42 ± 6.83 μmol/(min.g VSS), respectively) at 4-hr HRT. Microbial response analysis showed that the dominant microbial community was obviously shifted and the dominance of Anammox bacteria was enhanced durinR the hydrodynamic selection. 相似文献
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