染色体步移法克隆Pandoraea sp. BD-33硝基苯硝基还原酶基因

硝基还原酶是一种对辅酶烟酰胺腺嘌呤二核苷酸磷酸(NADPH)、烟酰胺腺嘌呤二核苷酸(NADH)以及黄素腺嘌呤二核苷酸(FAD)依赖性还原酶,本研究克隆的硝基苯硝基还原酶NN-BD-33是其中一种,它依赖于NADPH,以硝基苯维底物催化降解硝基苯成羟基苯胺,同时辅酶NADPH被氧化为NADP+。以公开报道的硝基苯硝基还原酶同源序列为参考,通过染色体步移法从Pandoraea sp.BD-33菌株中克隆得到硝基苯硝基还原酶基因。将为进一步深入研究硝基苯硝基还原酶的蛋白三维结构和作用机理奠定基础。

Effects of Stone Cutting Powder (Al-Khamkha) on the Properties of Self-Compacting Concrete

Most of the construction materials research now concerns on investigation of construction materials that is locally produced at a rate and cost compatible with the pace of construction. The present paper is concerned with investigation of fresh and hardened properties of self-compacting concrete (SCC) produced from local available materials in JORDAN. The produced SCC contains the local stone cut waste powder which is called Al-KHAMKHA in JORDAN with different replacement of (0%, 10%, and 25%) of fine silica aggregate;?the study also investigatesthe effects of SP33 super?plasticizer which is used by different doses (1%, 1.5% and 2%) for cement. The slump flow and the compressive strength of SCC were studied and the experimental results indicate the possibility of using Al-KHAMKHA in the production of SCC as the results showed that the compressive strength of the SCC with 10 % replacement by al-khamkha together with 1% SP33?super plasticizer was higher compared to pure SCC without al-khamkha;?the results also showed that as al-khamkha content increased the slump flow decreased.

Enterobactersp.NG-33菌株对玉米根系及植株中氮磷钾含量的影响

Enterobacter sp.NG-33是新筛选分离到能高效溶解不溶性无机磷且产吲哚乙酸的菌株。本研究采用盆栽方式,分析在黄潮土与缺磷土壤中,接种Enterobacter sp.NG-33对苗期玉米的根系发育及植株中氮磷钾含量的变化,探索菌株NG-33在不同土壤条件对苗期玉米生长的促生机制。结果表明,菌株NG-33能够在不同土壤条件下,提高玉米根系的根长、表面积、从根数目和分枝数,促进玉米根系的发育。在缺磷条件下,NG-33菌株促进了玉米根系对磷元素的吸收。而在黄潮土壤中该菌株可以促进玉米根系对氮和钾元素的吸收作用。因此,在土壤中接种Enterobacter sp.NG-33菌株能促进苗期玉米根系的发育并改善植株对氮、磷和钾元素的吸收。