Products of photosynthesis in natural populations of marine phytoplankton from the Gulf of Maine
Products of photosynthesis in natural populations of marine phytoplankton from the Gulf of Maine
复制标题
缅因湾海洋浮游植物自然种群的光合作用产物
DOI：
10.1007/bf00388921
复制
发表时间：
1978
期刊：
影响因子：
2.4
通讯作者：
W. Skea
中科院分区：
文献类型：
--
作者：
L. Morris;W. Skea
我们测量了 14C-二氧化碳光合同化成 (1) 乙醇可溶性、(2) 热三氯乙酸 (TCA) 可溶性（多糖）和 (3) 海洋浮游植物天然种群的蛋白质组分的情况。昼夜研究表明，在黑暗的几个小时内，碳 14 会持续掺入蛋白质部分。这伴随着同化为多糖的比例的减少。当在恒定的实验条件下测量掺入时，光合作用的模式在一天中的某个时间与另一个时间之间没有变化。在布斯贝港以南约 12 公里处的一个监测站，进入蛋白质的碳比例显示出明显的季节性变化。在冬季，大约 10% 至 20% 的固定碳被转化为蛋白质。夏季期间，该值增加至 22% 至 35%。在这些时间之间，进入蛋白质的固定碳的短暂高值达到 37% 至 47%，与春季开花相一致。掺入蛋白质的比例的增加在很大程度上与多糖部分的相应减少是平行的。在光合作用过程中掺入蛋白质的碳比例在光强度降低时也显着增加。当群体在中性密度滤光片中孵育时以及在透光区中以增加的深度孵育时，这种增加都会发生。中性密度滤光片和水柱深度之间几乎没有一致且显着的差异，这表明光质量的作用很小。较低光强下蛋白质合成相对速率增加的程度取决于浮游植物的营养状态。例如，夏季，生活在无机养分浓度较低的水中的种群，与生活在营养丰富的水域中的种群相比，对光照强度降低的反应不那么显着。
We have measured the photosynthetic assimilation of 14C-carbon dioxide into (1) ethanol-soluble, (2) hot-trichloroacetic acid (TCA)-soluble (polysaccharide), and (3) protein fractions of natural populations of marine phytoplankton. Diurnal studies showed a continuing incorporation of carbon-14 into the protein fraction during hours of darkness. This was accompanied by a concomitant decrease in the proportion assimilated into polysaccharide. When incorporation was measured under constant experimental conditions, the pattern of photosynthesis did not vary from one time of day to another. At one station approximately 12 km south of Boothbay Harbor, the proportion of carbon entering protein showed marked seasonal changes. During the winter, approximately 10 to 20% of the fixed carbon was incorporated into protein. During the summer the value increased to 22 to 35%. Between these times, a transient high value of 37 to 47% of the fixed carbon entering protein coincided with the spring bloom. The increases in proportion incorporated into protein were largely paralleled by equivalent decreases in the polysaccharide fraction. The proportion of carbon incorporated into protein during photosynthesis also increased markedly at reduced light intensities. This increase occurred both when populations were incubated in neutral-density filters and when incubated at increasing depths in the photic zone. There was little consistent and significant difference between the neutral-density filters and depth in the water column, suggesting a minimal role for light quality. The extent of the increased relative rate of protein synthesis at the lower light intensities depended on the nutritional state of the phytoplankton. For example, summer populations from water containing low concentrations of inorganic nutrients responded less dramatically to reduced light intensities than did populations from nutrient-rich waters.