Phosphate-limited ocean regions select for bacterial populations enriched in the carbon-phosphorus lyase pathway for phosphonate degradation
Phosphate-limited ocean regions select for bacterial populations enriched in the carbon-phosphorus lyase pathway for phosphonate degradation
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DOI：
10.1111/1462-2920.14628
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发表时间：
2019-07-01
影响因子：
5.1
通讯作者：
Karl, David M.
中科院分区：
文献类型：
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作者：
Sosa, Oscar A.;Repeta, Daniel J.;Karl, David M.
在热带和亚热带海洋表层沃茨，磷酸盐的缺乏会限制微生物的生产力。然而，这些环境也有生物可利用形式的磷纳入溶解有机物（DOM），微生物与必要的运输和水解代谢途径可以访问，以补充其磷的需求。在这项研究中，我们评估了环境如何塑造细菌碳-磷（C-P）裂解酶途径的丰度和分类分布，这是一种从膦酸盐中提取磷酸盐的酶复合物。膦酸盐是一种有机磷化合物，具有高度稳定的C-P键，在海洋DOM中富集。与其他已知的细菌适应低磷酸盐环境相似，发现C-P裂解酶随着磷酸盐浓度降低而变得更加普遍。C-P裂解酶在地中海和北大西洋特别丰富，这两个地区的特点是持续的磷酸盐耗尽期。在这些区域，C-P裂解酶在α-变形菌门（Pelagibacter、SAR 116、Roseflora和Rhodoacetillales）、γ-变形菌门和放线菌门的几个谱系中普遍存在。该分析的全球范围支持先前的研究，即推断磷酸盐催化剂通过C-P裂解酶是细菌实施的一种重要的适应性策略，以减轻磷酸盐限制，并扩大了海洋中这种代谢途径的已知地理范围和分类学联系。
In tropical and subtropical oceanic surface waters phosphate scarcity can limit microbial productivity. However, these environments also have bioavailable forms of phosphorus incorporated into dissolved organic matter (DOM) that microbes with the necessary transport and hydrolysis metabolic pathways can access to supplement their phosphorus requirements. In this study we evaluated how the environment shapes the abundance and taxonomic distribution of the bacterial carbon-phosphorus (C-P) lyase pathway, an enzyme complex evolved to extract phosphate from phosphonates. Phosphonates are organophosphorus compounds characterized by a highly stable C-P bond and are enriched in marine DOM. Similar to other known bacterial adaptions to low phosphate environments, C-P lyase was found to become more prevalent as phosphate concentrations decreased. C-P lyase was particularly enriched in the Mediterranean Sea and North Atlantic Ocean, two regions that feature sustained periods of phosphate depletion. In these regions, C-P lyase was prevalent in several lineages of Alphaproteobacteria (Pelagibacter, SAR116, Roseobacter and Rhodospirillales), Gammaproteobacteria, and Actinobacteria. The global scope of this analysis supports previous studies that infer phosphonate catabolism via C-P lyase is an important adaptive strategy implemented by bacteria to alleviate phosphate limitation and expands the known geographic extent and taxonomic affiliation of this metabolic pathway in the ocean.