不同碳源条件下草菇内切型纤维素酶基因（eg1）转录表达的分析

利用Northernblot方法分析了不同碳源条件下草菇切型纤维素酶基因(eg1)的表达.结果发现,在含有纤维素的液体培养基中生长10d,eg1在草菇菌丝中有高效表达;纤维二糖、α-乳糖、β-乳糖,也能诱导eg1的表达,但和纤维素相比,eg1的表达量相对较低,并且它们的诱导效应在加入这类糖12h后迅速减弱;槐糖和龙胆二糖的诱导作用非常弱.在天然稻草为基质的固体栽培料生长时,草菇eg1的表达和草菇菌丝生长与出菇相对应,在菌丝生长期(d8)可见eg1的表达,d12时菌丝已长满,表达减弱,在出菇及菇体的分化及增大期,eg1的表达量逐渐增强,在成熟期达到最高水平;表明在草菇菇体发育中需要更多碳源及能源的补充,eg1在这方面起着非常重要的作用.图4参14     

Groundwater quality of north-east Libya

The quality of groundwater was assessed to their suitability for drinking at six places of north-east Libya viz. El-Marj, Albayda, Shahat, Susa, Ras al-Hilal and Derna, during November, 2003 to March, 2004, by determining their physicochemical parameters (17 parameters) and water quality index (15 parameters). The temperatures of water samples averaged 15.1 degree C, pH values were alkaline and dissolved oxygen values were in safe ranges. Electrical conductivity, total dissolved solids and hardness of water at all places except Susa were within the standard limits. Alkalinity of well water at all six places exceeded, and chlorine and chloride (except Susa) were within the desirable limits set for them. Fluoride and nitrate contaminations of well water were not observed, and only very low values of phosphorus, manganese, chromium, iron and zinc were recorded. Copper in well water was generally high, and at Susa and Ras al-Hilal, it exceeded the desirable limit. Parametric ratios showed that all parameters studied except those of pH, dissolved oxygen, alkalinity and total chlorine originated from sources different from that of hardness. Water quality index (WQI) revealed that well water of Albayda and Shahat were good for drinking and were only slightly polluted, whereas those of El-Marj, Ras al-Hilal and Derna were moderately polluted. However, the well water of Susa was excessively polluted and was unsuitable for drinking. Suitable suggestions were made to improve the quality of groundwater of N.E. Libya.     

不同碳源条件下草菇内切型纤维素酶基因(egl)转录表达的分析

利用Northern blot方法分析了不同碳源条件下草菇內切型纤维素酶基因(eg1)的表达.结果发现,在含有纤维素的液体培养基中生长10 d,eg1在草菇菌丝中有高效表达;纤维二糖、α-乳糖、β-乳糖,也能诱导eg1的表达,但和纤维素相比,eg1的表达量相对较低,并且它们的诱导效应在加入这类糖12 h后迅速减弱;槐糖和龙胆二糖的诱导作用非常弱.在天然稻草为基质的固体栽培料生长时,草菇eg1的表达和草菇菌丝生长与出菇相对应,在菌丝生长期(d 8)可见eg1的表达,d 12时菌丝已长满,表达减弱,在出菇及菇体的分化及增大期,eg1的表达量逐渐增强,在成熟期达到最高水平;表明在草菇菇体发育中需要更多碳源及能源的补充,eg1在这方面起着非常重要的作用. 图4 参14