A preliminary study on air microorganism in a wood mill

The air microbial species and quantities in a wood mill in Harbin, China weremeasured using sedimentation plate method. Results showed that the microbial quantity in the air atthe workshop without depurator (54939 cfu·m^(-3)) was 2.1 times that of the workshop withdepu-rator (25768 cfu·m^(-3)). The depurator could purify air microorganisms at the workshop, witha purifying rate of 53.1%, but it did not reach the standards of clean air. Comparatively thedepurator is effective in reducing the quantity of air actinomyces, and some kinds of airactinomyces, such as Scabies, Cinereas and Hygroscopicas, can be clean out, but it is not veryeffective to bacteria and fungi. It is suggested that more effective and feasible methods should bedeveloped for purifying air microorganisms at the workshop in the future.

一种快速高效的水稻原生质体制备和转化方法的建立

在模式植物拟南芥中,原生质体瞬时表达技术已被广泛地应用到功能基因组学的研究中,但水稻原生质体因其制备过程相对繁琐,转化效率偏低,尚未在基因功能研究中获得广泛应用。本研究在拟南芥原生质体制备和转化的基础之上,对水稻原生质体的制备和转化方法进行改良优化。以水稻幼茎为起始材料,采用纤维素酶R-10和果胶酶R-10,对水稻组织进行消化并利用蔗糖密度梯度自沉降的方法分离原生质体,获得了高纯度的原生质体。对质粒转化原生质体时的转化方法、转化时间及质粒浓度进行探索,在缩短原生质体分离时间的同时,大大提高了转化效率。用较少量的质粒DNA即可获得外源基因在原生质体内高效的表达,且转化效率可达70%。我们建立的这种快速有效的水稻原生质体制备和转化方法,可为水稻功能基因组学研究提供技术支持。