College of Life Sciences, Shihezi University, Shihezi, 832003, People's Republic of China.
Xinjiang Fufeng Biotechnology Co., Ltd., Ürümqi, 830001, Xinjiang, People's Republic of China.
World J Microbiol Biotechnol. 2021 May 13;37(6):100. doi: 10.1007/s11274-021-03068-5.
Methylobacterium sp. CLZ was isolated from soil contaminated with chemical wastewater. This strain simultaneously synthesizes Pyrroloquinoline quinone (PQQ), Coenzyme Q10 (CoQ10), and carotenoids by utilizing methanol as a carbon source. Comparative genomic analysis was performed for five Methylobacterium strains. As per the outcomes, the Methylobacterium CLZ strain showed the smallest genome size and the lowest number of proteins. Thus, it can serve as an ideal cell model for investigating the biological process of Methylobacterium and constructing genetically engineered Methylobacterium. The Methylobacterium CLZ strain's pqqL gene, which does not occur in other Methylobacterium strains but plays a crucial role in PQQ synthesis. This was a surprising finding for the study of PQQ biosynthesis in Methylobacterium. Methylobacterium sp. NI91 strain was generated by random mutagenesis of CLZ strain, and NI91 strain showed a 72.44% increase in PQQ yield. The mutation in the mxaJ gene involved in the methanol dehydrogenase (MDH) synthesis was identified through comparative genomic analysis of the whole genome of mutant strain NI91 and wild-type strain CLZ. The mxaJ gene was found to be upregulated in the NI91 strain. Thus, the up-regulation of the mxaJ gene could be correlated with the high yield of PQQ, and it could provide valuable clues for strain engineering to improve PQQ production.
甲基杆菌 sp. CLZ 从受化学废水污染的土壤中分离出来。该菌株通过利用甲醇作为碳源，同时合成吡咯喹啉醌 (PQQ)、辅酶 Q10 (CoQ10) 和类胡萝卜素。对 5 株甲基杆菌进行了比较基因组分析。结果表明，CLZ 菌株的基因组最小，蛋白数量最少。因此，它可以作为研究甲基杆菌生物学过程和构建基因工程甲基杆菌的理想细胞模型。CLZ 菌株的 pqqL 基因在其他甲基杆菌菌株中不存在，但对 PQQ 合成起着关键作用。这一发现对于研究甲基杆菌中 PQQ 的生物合成具有重要意义。通过对 CLZ 菌株进行随机诱变，得到甲基杆菌 NI91 菌株，其 PQQ 产量提高了 72.44%。通过比较基因组分析突变株 NI91 和野生型 CLZ 的全基因组，发现突变株 NI91 中参与甲醇脱氢酶 (MDH) 合成的 mxaJ 基因发生了突变。发现 mxaJ 基因在 NI91 菌株中上调。因此，mxaJ 基因的上调可能与 PQQ 的高产有关，这为提高 PQQ 产量的菌株工程提供了有价值的线索。
