Ge Fanglan, Wen Dongmei, Ren Yao, Chen Guiying, He Bing, Li Xiaokun, Li Wei
College of Life Sciences, Sichuan Normal University, Chengdu, 610068 People's Republic of China.
Key Laboratory for Utilization and Conservation of Bio-Resources of Education, Department of Sichuan Province, Chengdu, People's Republic of China.
3 Biotech. 2021 May;11(5):230. doi: 10.1007/s13205-021-02733-8. Epub 2021 Apr 21.
Aminolevulinic acid (ALA), a type of natural non-protein amino acid, is a key precursor for the biosynthesis of heme, and it has been broadly applied in medicine, agriculture. Several strategies have been applied to enhance ALA synthesis in bacteria. In the present study, we employed synthetic antisense RNAs (asRNAs) of (encodes ALA dehydratase) to weaken metabolic flux of ALA to porphobilinogen (PBG), and investigated their effect on ALA accumulation. For this purpose, we designed and constructed vectors pET28a-hemA-asRNA and pRSFDuet-hemA-asRNA to simultaneously express 5-ALA synthase (ALAS, encoded by ) and PTasRNAs (2 inverted repeat DNA sequences sandwiched with the antisense sequence of ), selecting the region ranging from - 57 nt upstream to + 139 nt downstream of the start codon of as a target. The qRT-PCR analysis showed that the mRNA levels of were decreased above 50% of the control levels, suggesting that the anti-hemB asRNA was functioning appropriately. ALA accumulation in the hemB weakened strains were 17.6% higher than that obtained using the control strains while accumulating less PBG. These results indicated that asRNAs can be used as a tool for regulating ALA accumulation in .
The online version contains supplementary material available at 10.1007/s13205-021-02733-8.
氨基乙酰丙酸(ALA)是一种天然非蛋白质氨基酸,是血红素生物合成的关键前体,已广泛应用于医学、农业领域。已采用多种策略来增强细菌中ALA的合成。在本研究中,我们利用编码ALA脱水酶的hemB的合成反义RNA(asRNAs)来减弱ALA向胆色素原(PBG)的代谢通量,并研究它们对ALA积累的影响。为此,我们设计并构建了载体pET28a-hemA-asRNA和pRSFDuet-hemA-asRNA,以同时表达5-ALA合酶(由hemA编码的ALAS)和PTasRNAs(2个反向重复DNA序列夹着hemB的反义序列),选择hemB起始密码子上游-57 nt至下游+139 nt的区域作为靶标。qRT-PCR分析表明,hemB的mRNA水平降低至对照水平的50%以上,表明抗hemB asRNA发挥了适当的作用。hemB弱化菌株中的ALA积累比对照菌株高17.6%,同时积累的PBG较少。这些结果表明,asRNAs可作为调节大肠杆菌中ALA积累的工具。
在线版本包含可在10.1007/s13205-021-02733-8获取的补充材料。