Xia Yu, Wei Zhi-Yuan, He Rui, Li Jia-Huan, Wang Zhi-Xin, Huo Jun-Da, Chen Jian-Huan
State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.
School of Food Science and Technology, Jiangnan University, Wuxi, China.
Front Microbiol. 2021 Nov 11;12:783195. doi: 10.3389/fmicb.2021.783195. eCollection 2021.
Our previous study identified a new β-galactosidase in sp. E602. To further understand the lactose metabolism in this strain, genome assembly was conducted by using a strategy combining Illumina and PacBio sequencing technology. The whole genome of sp. E602 includes a 4.8 Mb chromosome and a 326 kb large plasmid. A total of 4,739 genes, including 4,543 protein-coding genes, 25 rRNAs, 82 tRNAs and 7 other ncRNAs genes were annotated. The plasmid was the largest one characterized in genus by far, and it contained a number of genes and pathways responsible for lactose metabolism and regulation. Moreover, a new plasmid-borne operon that lacked a typical β-galactoside transacetylase () gene was identified in the strain. Phylogenetic analysis showed that the genes and in the operon were under positive selection, indicating the adaptation of lactose metabolism to the environment in sp. E602. Our current study demonstrated that the hybrid genome assembly using Illumina and PacBio sequencing technologies, as well as the metabolic pathway analysis, provided a useful strategy for better understanding of the evolution of undiscovered microbial species or strains.
我们之前的研究在sp. E602中鉴定出一种新的β-半乳糖苷酶。为了进一步了解该菌株中的乳糖代谢，采用Illumina和PacBio测序技术相结合的策略进行了基因组组装。sp. E602的全基因组包括一条4.8 Mb的染色体和一个326 kb的大质粒。总共注释了4739个基因，包括4543个蛋白质编码基因、25个rRNA、82个tRNA和7个其他非编码RNA基因。该质粒是迄今为止在该属中鉴定出的最大质粒，它包含许多负责乳糖代谢和调控的基因及途径。此外，在该菌株中鉴定出一个新的质粒携带的操纵子，该操纵子缺少典型的β-半乳糖苷转乙酰酶（）基因。系统发育分析表明，该操纵子中的基因和处于正选择状态，表明sp. E602中乳糖代谢对环境的适应性。我们目前的研究表明，使用Illumina和PacBio测序技术进行混合基因组组装以及代谢途径分析，为更好地理解未发现的微生物物种或菌株的进化提供了一种有用的策略。
