摘要
以小麦(Triticumaestivum)返白系F772为材料,通过粗提、加热处理、硫酸铵分级沉淀和凝胶柱层析等方法,对胆色素原脱氨酶(PBGD)进行了提取纯化,纯化倍数为1092,得率为15%.纯化的PBGD约为37kD.对其部分生化性质的研究表明:高浓度的NH4+对酶活性有强烈的抑制,光照处理可以使酶活性降低.对纯化后的PBGDN末端氨基酸序列进行了测定.根据N端序列设计简并引物,获得了PBGD的cDNA全部编码区序列.它编码一个351个氨基酸的前体蛋白,有一个叶绿体导肽的序列.通过比较小麦PBGD与来自与其他物种的同源蛋白表明,有些氨基酸残基非常保守.
Porphobilinogen deaminase （PBGD） was purified from F772, a mutant of ＇the stage albinism line of wheat＇, following the procedures including crude extracts, heat treatment, ammonium sulfate fraction and column chromatography. The enzyme was purified 1 092 fold with a special activity recovery of 15%. The wheat PBGD is a 37 kD protein. The activity of enzyme could be greatly inhibited by high contents of ammonium ion as well as lighting treatment. The N-terminal amino acid sequence was determined for PBGD, based on which, PBGD cDNA was obtained with the degenerate primers. Sequence analysis of coding region of PBGD indicated that it encodes a precursor of 351 residues with a typical chloroplast-targeted peptide. In comparison of wheat PBGD and its homologs from other species, it was found that there are some highly conserved amino acid residues among these proteins.
出处
《中国生物化学与分子生物学报》
CAS
CSCD
北大核心
2006年第12期973-978,共6页
Chinese Journal of Biochemistry and Molecular Biology
基金
国家自然科学基金项目(No.39570066)
教育部博士点基金(No.1998071233)资助~~
关键词
小麦返白系
胆色素原脱氨酶
N末端氨基酸测序
纯化
CDNA克隆
the stage albinism line of wheat
porphobilinogen deaminase
N-terminal amino acid sequencing
purification
cDNA cloning
