...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Estuarine Coastal and Shelf Science >Alkaline phosphatase activity of water column fractions and seagrass in a tropical carbonate estuary, Florida Bay
【24h】

Alkaline phosphatase activity of water column fractions and seagrass in a tropical carbonate estuary, Florida Bay

机译：热带碳酸盐河口，佛罗里达湾水柱级分和海草的碱性磷酸酶活性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Few phosphorus-depleted coastal ecosystems have been examined for their ability to hydrolyze phos-phomonoesters. We examined seasonal (August 2006-April 2007) alkaline phosphatase activity in Florida Bay, a phosphorus-limited shallow estuary, using fluorescent substrate at low concentrations (≤2.0 μM). In situ dissolved inorganic and organic phosphorus levels and phosphomonoester concentrations were also determined. Water column alkaline phosphatase activity was partitioned into two paniculate size fractions (>1.2 and 0.2-1.2 μm) and freely dissolved enzymes (<0.2 μm). Water column alkaline phosphatase activity was also compared to leaf and epiphyte activity of the dominant tropical seagrass Thalassia testudinum. Our results indicate: (1) potential alkaline phosphatase activity in Florida Bay is high compared to other marine ecosystems, resulting in rapid phosphomonoester turnover times (～2h). (2) Water column alkaline phosphatase activity dominates, and is split equally between paniculate and dissolved fractions. (3) Alkaline phosphatase activity was highest during cyanobacterial blooms, but not when normalized to chl a. These results suggest that dissolved, heterotrophic and autotrophic alkaline phosphatase activity is stimulated by phytoplankton blooms. (4) The dissolved alkaline phosphatase activity is relatively constant, while the paniculate activity is seasonally and spatially dynamic, typically associated with phytoplankton blooms. (5) Phosphomonoester concentrations throughout the bay are low, even though potential hydrolysis rates are high. We propose that bioavailable dissolved organic P is hydrolyzed by dissolved and microbial alkaline phosphatase enzymes in Florida Bay. High alkaline phosphatase activity in the bay is also promoted by long hydraulic residence times. This background activity is primarily driven by carbon and phosphorus limitation of microorganisms, and regeneration of enzymes associated with cell lysis. Pulses of inorganic phosphorus and labile organic phosphorus and nitrogen may stimulate autotrophs, particularly cyanobacteria, which in turn promote biological activity that increase alkaline phosphatase activity of both autotrophs and heterotrophs in the bay.
机译：很少有人研究过贫磷的沿海生态系统水解磷-单酯的能力。我们使用低浓度（≤2.0μM）的荧光底物检查了磷受限的浅河口佛罗里达湾的季节性（2006年8月至2007年4月）碱性磷酸酶活性。还确定了原位溶解的无机和有机磷水平以及磷酸单酯浓度。将水柱碱性磷酸酶活性分为两个颗粒大小的部分（> 1.2和0.2-1.2μm）和自由溶解的酶（<0.2μm）。还比较了水柱碱性磷酸酶的活性与主要热带海草塔氏藻的叶和附生植物的活性。我们的结果表明：（1）与其他海洋生态系统相比，佛罗里达湾的潜在碱性磷酸酶活性较高，从而导致磷酸单酯的转换时间迅速（〜2h）。 （2）水柱碱性磷酸酶活性占优势，并且在颗粒级分和溶解级分之间均分。 （3）碱性磷酸酶活性在蓝藻水华期间最高，但当标准化为chl a时则不是。这些结果表明，浮游植物水华刺激了溶解的，异养的和自养的碱性磷酸酶活性。 （4）溶解的碱性磷酸酶活性相对恒定，而颗粒活性具有季节性和空间动态性，通常与浮游植物的开花有关。 （5）即使潜在的水解速率很高，整个海湾的磷酸单酯浓度仍然很低。我们建议生物利用的溶解性有机磷被佛罗里达湾的溶解性和微生物碱性磷酸酶水解。较长的水力停留时间也促进了海湾中的高碱性磷酸酶活性。这种背景活性主要由微生物对碳和磷的限制以及与细胞裂解有关的酶的再生驱动。无机磷和不稳定的有机磷和氮的脉冲可能会刺激自养生物，特别是蓝细菌，从而促进生物活性，从而增加海湾中自养生物和异养生物的碱性磷酸酶活性。

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