Xu Anming, Wang Di, Ding Yichen, Zheng Yaqian, Wang Bo, Wei Qing, Wang Shiwei, Yang Liang, Ma Luyan Z
State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
University of Chinese Academy of Sciences, Beijing, China.
Front Microbiol. 2020 Mar 31;11:519. doi: 10.3389/fmicb.2020.00519. eCollection 2020.
is an environmental microorganism that can thrive in diverse ecological niches including plants, animals, water, soil, and crude oil. It also one of the microorganism widely used in tertiary recovery of crude oil and bioremediation. However, the genomic information regarding the mechanisms of survival and adapation of this bacterium in crude oil is still limited. In this study, three strains (named as IMP66, IMP67, and IMP68) isolated from crude oil were taken for whole-genome sequencing by using a hybridized PacBio and Illumina approach. The phylogeny analysis showed that the three strains were all species and clustered in clade 1, the group with PAO1 as a representitive. Subsequent comparative genomic analysis revealed a high degree of individual genomic plasticity, with a probable alkane degradation genomic island, one type I-F CRISPR-Cas system and several prophages integrated into their genomes. Nine genes encoding alkane hydroxylases (AHs) homologs were found in each strain, which might enable these strains to degrade alkane in crude oil. can produce rhamnolipids (RLs) biosurfactant to emulsify oil, which enables their survival in crude oil enviroments. Our previous report showed that IMP67 and IMP68 were high RLs producers, while IMP66 produced little RLs. Genomic analysis suggested that their RLs yield was not likely due to differences at genetic level. We then further analyzed the quorum sensing (QS) signal molecules that regulate RLs synthesis. IMP67 and IMP68 produced more N-acyl-homoserine lactones (AHLs) signal molecules than that of PAO1 and IMP66, which could explain their high RLs yield. This study provides evidence for adaptation of in crude oil and proposes the potential application of IMP67 and IMP68 in microbial-enhanced oil recovery and bioremediation.
是一种环境微生物，能在包括植物、动物、水、土壤和原油在内的多种生态位中茁壮成长。它也是广泛用于原油三次采油和生物修复的微生物之一。然而，关于这种细菌在原油中生存和适应机制的基因组信息仍然有限。在本研究中，采用PacBio和Illumina杂交方法对从原油中分离出的三株菌（命名为IMP66、IMP67和IMP68）进行全基因组测序。系统发育分析表明，这三株菌均为 种，聚集在进化枝1中，该组以PAO1为代表。随后的比较基因组分析揭示了高度的个体基因组可塑性，其基因组中可能存在一个烷烃降解基因组岛、一个I-F型CRISPR-Cas系统和几个原噬菌体。在每株菌中发现了九个编码烷烃羟化酶（AHs）同源物的基因，这可能使这些菌株能够降解原油中的烷烃。 能产生鼠李糖脂（RLs）生物表面活性剂来乳化油，使其能够在原油环境中生存。我们之前的报告显示，IMP67和IMP68是高RLs生产者，而IMP66产生的RLs很少。基因组分析表明，它们的RLs产量不太可能是由于基因水平的差异。然后，我们进一步分析了调节RLs合成的群体感应（QS）信号分子。IMP67和IMP68产生的N-酰基高丝氨酸内酯（AHLs）信号分子比PAO1和IMP66多，这可以解释它们的高RLs产量。本研究为 在原油中的适应性提供了证据，并提出了IMP67和IMP68在微生物强化采油和生物修复中的潜在应用。
