慢生型大豆根瘤菌(Bradyrhizobium japonicum)USDA110菌株3-羟丁酸脱氢酶基因(bdhA)的克隆、序列及特性  

Cloning, Sequence and Characteristics of 3-Hydroxybutyrate Dehydrogenase Encoding Gene (bdhA) in Bradyrhizobium japonicum USDA110 Strain

作　　者：戴美学[1] 武波[2] 柏学亮[2] 张成刚[1] 马庆生[2] Trevor C.Charles 

机构地区：[1]中国科学院沈阳应用生态研究所,沈阳110015 [2]广西大学/农业部农业分子遗传重点实验室,南宁530005 [3]滑铁卢大学生物系

出　　处：《中国农业科学》2003年第3期292-299,共8页Scientia Agricultura Sinica

摘　　要：通过功能互补试验 ,从慢生型大豆根瘤菌USDA110菌株基因文库中筛选到能互补广宿主根瘤菌NGR2 34的bdhA突变体菌株NGRPA2和苜蓿根瘤菌的bdhA突变体菌株Rm1110 7、使之恢复Hbu+ 表型的克隆 ;经酶活测定和Southern杂交证明该克隆含有bdhA基因。测定了bdhA基因全序列 ,并在GenBank登记 (登记号为 :AY0 775 81)。该基因由 789个碱基对组成 ,编码分子量为 2 7.5 9ku、含 2 6 2个氨基酸残基的 3 羟基丁酸脱氢酶。在该基因的开放阅读框内插入interposonΩKm ,并通过同源重组构建了BradyrhizobiumjaponicumbdhA突变体 (bdhA ::ΩKm)。植株试验未显示bdhA基因的突变对结瘤、固氮有明显影响。A clone which can restore the ability of bdhA mutant strains NGRPA2 and Rm11107 to utilize 3 hydroxybutyrate as sole carbon source (Hbu +) was screened out by complementation experiment from Bradyrhizobium japonicum USDA110 genomic library. It was confirmed by Bdh assay and Southern blot that this clone contains bdhA gene. The entire sequence of bdhA gene was sequenced and the sequence was deposited in GenBank at the accession number of AY077581. bdhA gene consists of 789 base pairs and encodes Bdh with 262 amino acid and MW 27.59 ku. Interposon ΩKm was inserted into the bdhA ORF at EcoRⅠsite and the bdhA mutant was constructed in B.japonicum by homologous recombination. Plant test result did not show obvious effects of mutation of bdhA gene on nodulation and nitrogen fixation.

关 键 词：慢性型大豆根瘤菌 3-羟丁酸脱氢酶 3-羟丁酸脱氢酶基因 聚羟丁酸 

分 类 号：Q78[生物学—分子生物学]