工业微生物2017，Vol.47Issue(3)：1-8,8.DOI:10.3969/j.issn.1001-6678.2017.03.001
不同来源的尿卟啉原Ⅲ转甲基酶在脱氮假单胞菌中的表达及其对生产维生素B12的影响
Over-expression uroporphyrinogen Ⅲ methyltransferase from different strains in Pseudomonas denitrificans and their effects on vitamin B12 production
摘要
Abstract
The carbon atoms in the center position of C-2 and C-7 of uroprophyrinogen Ⅲ (urogen Ⅲ) can be methylated to produce precorrin-2 by S-adenosy-L-methionine uroprophyrinogen Ⅲ methyltransferase (SUMT),which is the key enzyme of vitamin B12 (VB12) biosynthetic pathway.In this study,RCcobA1 and RCcobA2 from Rhodobacter capsulatus and PDcobA from Pseudomonas denitrificans were cloned and over-expressed in VB12-producing strains P.denitrificans.The resulting strains PD1/2/3/4 were fermented in shake flasks.The results showed that the VB12 production of PD2 (overexpressing PDcobA) increased 16.48％,the VB12 production of PD3 (overexpressing RCcobA1) and PD4 (overexpressing RCcobA2) increased 10.2％ and 31.86％ when compared with the control strain (PD1),respectively.According to the results of shaking flasks fermentation,the fermentation of the strains PD1 and PD4 in 5 L fermentor was conducted.The output of VB12 of PD4 was 144.5 mg/L,which increased by 29.83％ comparing to that of PD1 (111.3 mg/L).It revealed that the overexpression of cobA2,to a certain extent,could release the bottlenecks of VB12 synthetic pathway and increase the production of VB12.关键词
维生素B12/尿卟啉原Ⅲ转甲基酶/尿卟啉原Ⅲ/脱氮假单胞菌Key words
Vitamin B12/uroporphyrinogen Ⅲ methyltransferase/uroprophyrinogen Ⅱ/Pseudomonas denitrificans引用本文复制引用
程立芳,康洁,房欢,董会娜,花尔并,张大伟..不同来源的尿卟啉原Ⅲ转甲基酶在脱氮假单胞菌中的表达及其对生产维生素B12的影响[J].工业微生物,2017,47(3):1-8,8.基金项目
国家自然科学基金(No.21506244,31370089),天津市自然科学基金(14ZCZDSY00065,15JCQNJC09500,16JCYBJC23500)资助. （No.21506244,31370089）
