Comparative Biochemistry of the Aldoxime-Nitrile Pathway of Plant and Microbial Origins

点击翻译按钮获取中文摘要

1.Screening for plant aldoxime-Nitrile pathway and its utilization :(1)We have optimized the method of extraction of plant HNLs and made it possible to extend to plant screening for HNLs. A new method of HNL activity measurement by the use of HPLC was established.(2)In collaboration with the Botanic gardens of Toyama, HNL was screened from around 200 species of plants. (S)-HNL was discovered in Baliospermum montanum, (R)-HNL was found in P assiflora edulis, Eriobotrya japonica, Chaenomles sinensis, Sorbus aucuparia, Prunus mume, and Prunus persica.(3)(S)-HNL genes from Hevea brasilliensis and Manihot esculanta were synthesized.(4)cDNA was synthesized from Baliospermum montanum and DNA oligomers were synthesized according to the information from N-terminus amino acid sequence of the purified HNL from Baliospermum montanum. By hybridization, the HNL gene was cloned from the cDNA library. Expression the gene in E.coil was studied.(5)Substrate specificities of HNL from Eriobotrya japonica, Baliospermum montanum, Prunus mume were studied.2.Screening for microbial aldoxime-Nitrile pathway and its utilization :(1)We clarified that microbial aldoxime dehydratase gene is linked with the gene for nitrile metabolizing enzymes such as nitirlase, nitirile hydratase, and amidase, and proved its general distribution among microorganisms. We also shown that aldoxime dehydratase can be the key enzyme to prove the occurrence of in aldoxim-NItirle pathway. Various aldoxime dehydratase genes were cloned from microorganism.