Its genomic dna was partially digested by sauial . dna fragments from 4 to 16 kb were collected after electrophoresis and ligated with bamhi - digested puc18 to construct genomic library . the total number of recombinant plasmids is about 9000 进一步在opua基因的上下游序列分别设计引物,从h . trueperi基因组dna中扩增出所预期大小的片段,测序验证已获得opua基因的全序列。