Data_Sheet_1_Hydrocarbon-Degrading Bacteria Alcanivorax and Marinobacter Associated With Microalgae Pavlova lutheri and Nannochloropsis oculata.zip

Marine hydrocarbon-degrading bacteria play an important role in natural petroleum biodegradation processes and were initially associated with man-made oil spills or natural seeps. There is no full clarity though on what, in the absence of petroleum, their natural niches are. Few studies pointed at some marine microalgae that produce oleophilic compounds (alkanes, long-chain fatty acids, and alcohols) as potential natural hosts of these bacteria. We established Dansk crude oil-based enrichment cultures with photobioreactor-grown marine microalgae cultures Pavlova lutheri and Nannochloropsis oculata and analyzed the microbial succession using cultivation and SSU (16S) rRNA amplicon sequencing. We found that petroleum enforced a strong selection for members of Alpha- and Gamma-proteobacteria in both enrichment cultures with the prevalence of Alcanivorax and Marinobacter spp., well-known hydrocarbonoclastic bacteria. In total, 48 non-redundant bacterial strains were isolated and identified to represent genera Alcanivorax, Marinobacter, Thalassospira, Hyphomonas, Halomonas, Marinovum, Roseovarius, and Oleibacter, which were abundant in sequencing reads in both crude oil enrichments. Our assessment of public databases demonstrated some overlaps of geographical sites of isolation of Nannochloropsis and Pavlova with places of molecular detection and isolation of Alcanivorax and Marinobacter spp. Our study suggests that these globally important hydrocarbon-degrading bacteria are associated with P. lutheri and N. oculata.

海洋烃降解细菌在自然石油生物降解过程中扮演着至关重要的角色，最初与人为石油泄漏或自然渗漏有关。然而，在缺乏石油的情况下，它们在自然环境中的生态位尚不明确。少数研究指出，某些能够产生亲油化合物的海洋微藻（如烷烃、长链脂肪酸和醇类）可能是这些细菌的自然宿主。我们利用光生物反应器培养的海洋微藻Pavlova lutheri和Nannochloropsis oculata建立了以Dansk原油为基础的富集培养，并通过培养和SSU（16S）rRNA扩增子测序分析了微生物群落演替。我们发现，石油在富集培养中对α-和γ-变形菌具有强烈的筛选作用，其中以Alcanivorax和Marinobacter属等已知烃裂解菌的普遍存在为特征。总共分离和鉴定出48个非冗余细菌菌株，这些菌株代表Alcanivorax、Marinobacter、Thalassospira、Hyphomonas、Halomonas、Marinovum、Roseovarius和Oleibacter等属，这些属在原油富集培养的测序读数中含量丰富。我们对公共数据库的评估显示，Nannochloropsis和Pavlova的分离地点与Alcanivorax和Marinobacter属的分子检测和分离地点存在地理上的重叠。本研究表明，这些在全球范围内具有重要意义的烃降解细菌与P. lutheri和N. oculata密切相关。