...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The ISME journal emultidisciplinary journal of microbial ecology >Nutrient requirements for growth of the extreme oligotroph 'Candidatus Pelagibacter ubique' HTCC1062 on a defined medium
【24h】

Nutrient requirements for growth of the extreme oligotroph 'Candidatus Pelagibacter ubique' HTCC1062 on a defined medium

机译：在规定的培养基上生长极富营养性'Candidatus Pelagibacter ubique'HTCC1062的营养需求

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Chemoheterotrophic marine bacteria of the SAR11 clade are Earth's most abundant organisms. Following the first cultivation of a SAR11 bacterium, 'Candidatus Pelagibacter ubique' strain HTCC1062 (Ca. P. ubique) in 2002, unusual nutritional requirements were identified for reduced sulfur compounds and glycine or serine. These requirements were linked to genome streamlining resulting from selection for efficient resource utilization in nutrient-limited ocean habitats. Here we report the first successful cultivation of Ca. P. ubique on a defined artificial seawater medium (AMS1), and an additional requirement for pyruvate or pyruvate precursors. Optimal growth was observed with the collective addition of inorganic macro-and micronutrients, vitamins, methionine, glycine and pyruvate. Methionine served as the sole sulfur source but methionine and glycine were not sufficient to support growth. Optimal cell yields were obtained when the stoichiometry between glycine and pyruvate was 1:4, and incomplete cell division was observed in cultures starved for pyruvate. Glucose and oxaloacetate could fully replace pyruvate, but not acetate, taurine or a variety of tricarboxylic acid cycle intermediates. Moreover, both glycine betaine and serine could substitute for glycine. Interestingly, glycolate partially restored growth in the absence of glycine. We propose that this is the result of the use of glycolate, a product of phytoplankton metabolism, as both a carbon source for respiration and as a precursor to glycine. These findings are important because they provide support for the hypothesis that some micro-organisms are challenging to cultivate because of unusual nutrient requirements caused by streamlining selection and gene loss. Our findings also illustrate unusual metabolic rearrangements that adapt these cells to extreme oligotrophy, and underscore the challenge of reconstructing metabolism from genome sequences in organisms that have non-canonical metabolic pathways.
机译：SAR11进化支化的海洋化学细菌是地球上最丰富的生物。在2002年首次培养出SAR11细菌“ Candidatus Pelagibacter ubique”菌株HTCC1062（Ca。P. ubique）之后，人们发现了减少硫化合物和甘氨酸或丝氨酸的特殊营养需求。这些要求与因在营养有限的海洋生境中进行有效资源利用的选择而导致的基因组优化有关。在这里，我们报告了钙的首次成功栽培。在确定的人工海水介质（AMS1）上的P. ubique，以及对丙酮酸或丙酮酸前体的附加要求。集体添加无机常量营养素和微量营养素，维生素，蛋氨酸，甘氨酸和丙酮酸可观察到最佳生长。蛋氨酸是唯一的硫源，但蛋氨酸和甘氨酸不足以支持生长。当甘氨酸和丙酮酸之间的化学计量比为1：4时，可获得最佳的细胞产量，并且在缺乏丙酮酸的培养物中观察到细胞分裂不完全。葡萄糖和草酰乙酸可以完全替代丙酮酸，但不能替代乙酸盐，牛磺酸或各种三羧酸循环中间体。此外，甘氨酸甜菜碱和丝氨酸均可替代甘氨酸。有趣的是，乙醇酸在不存在甘氨酸的情况下部分恢复了生长。我们认为这是使用浮游植物代谢产物乙醇酸盐作为呼吸的碳源和甘氨酸的前体的结果。这些发现很重要，因为它们为以下假设提供了支持：某些微生物由于精简选择和基因损失而导致营养需求异常，难以培养。我们的发现还说明了使这些细胞适应极端寡营养的异常代谢重排，并强调了从具有非规范代谢途径的生物体中的基因组序列重建代谢的挑战。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号