1·These plasmids occur naturally in nature; they were discovered in micro-organisms and they also confer some biological properties onto micro-organisms.
这些质粒在自然界中自然存在；它们是在微生物中发现的，它们也赋予了微生物一些生物学特性。
2·New phages can develop by acquiring restriction enzymes from plasmids.
通过从质粒获得的限制性酶，新的噬菌体能够生长。
3·These plasmids can be used in the study of foreign gene expression in yeast.
这些质粒可用于外源基因在酵母中表达的研究。
4·Apply the technique of vector recombine to acquire recombinant plasmids.
运用载体重组技术进行质粒重组；
5·Objective To study the distribution of plasmids in drug resistance bacteria of nosocomial infections.
目的了解医院内感染耐药性菌质粒的分布情况。