Identification of sibling species of the bryozoan Bugula neritina that produce different anticancer bryostatins and harbor distinct strains of the bacterial symbiont "Candidatus endobugula sertula"
Identification of sibling species of the bryozoan Bugula neritina that produce different anticancer bryostatins and harbor distinct strains of the bacterial symbiont "Candidatus endobugula sertula"
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DOI：
10.2307/1542952
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发表时间：
1999-06-01
影响因子：
1.6
通讯作者：
Haygood, MG
中科院分区：
文献类型：
--
作者：
Davidson, SK;Haygood, MG
尽管世界性的海洋苔藓动物 Bugula neritina 被认为是单一物种，但这种苔藓动物的天然产物因种群而异。 B. neritina 是候选抗癌药物苔藓抑素 i 的来源，但它也产生其他苔藓抑素，并且不同人群含有不同的苔藓抑素。我们根据之前的研究定义了两种化学型： 化学型：O 包含带有八-2,4-二烯酸酯取代基的苔藓抑素（包括苔藓抑素 i），以及其他苔藓抑素；化学型 M 缺乏带有八-2,4-二烯酸酯取代基的苔藓抑素。 B. neritina 含有一种共生的 γ-变形菌“Candidatus Endobugula sertula”，并且有人提出苔藓抑素可能是由细菌共生体合成的。在这项研究中，对加州海岸沿线的 B. neritina 群体进行了遗传变异和苔藓抑素含量采样。化学型不同的菌落在遗传上也存在 8% 的差异。 线粒体细胞色素c氧化酶亚基1（CO I）基因；这种差异足以表明化学型代表不同的物种。每个物种都含有独特的“E. sertula”，其小亚基核糖体 RNA (SSU rRNA) 基因中的四个核苷酸位点有所不同。这些结果表明，化学型具有遗传基础，而不是环境原因。来自大西洋样本的基因序列与来自加利福尼亚化学型 M 菌落的序列相匹配，表明这种类型可能由于在船体上运输而具有世界性。
Although the cosmopolitan marine bryozoan Bugula neritina is recognized as a single species, natural products from this bryozoan vary among populations. B. neritina is the source of the anticancer drug candidate bryostatin i, but it also produces other bryostatins, and different populations contain different bryostatins. We defined two chemotypes on the basis of previous studies: chemotype: O contains bryostatins with an octa-2,4-dienoate substituent (including bryostatin i), as well as other bryostatins; chemotype M lacks bryostatins with the octa-2,4-dienoate substituent. B. neritina contains a symbiotic gamma-proteobacterium "Candidatus Endobugula sertula,'' and it has been proposed that bryostatins may be synthesized by bacterial symbionts. In this study, B. neritina populations along the California coast were sampled for genetic variation and bryostatin content. Colonies that differ in chemotype also differ genetically by 8% in the mitochondrial cytochrome c oxidase subunit 1 (CO I) gene; this difference is sufficient to suggest that the chemotypes represent different species. Each species contains a distinct strain of "E. sertula" that differs at four nucleotide sites in the small subunit ribosomal RNA (SSU rRNA) gene. These results indicate that the chemotypes have a genetic basis rather than an environmental cause. Gene sequences from an Atlantic sample matched sequences from the California chemotype M colonies, suggesting that this type may be cosmopolitan due to transport on boat hulls.