Department of Biological Oceanography, Royal Netherlands Institute for Sea Research, Den Burg, Texel, Netherlands.
Appl Environ Microbiol. 2012 Sep;78(18):6741-8. doi: 10.1128/AEM.01388-12. Epub 2012 Jul 13.
Lytic and lysogenic viral infection was investigated throughout the Southern Ocean at sites spanning the sub-Antarctic zone, the Antarctic Circumpolar Current, and an Antarctic continental sea. Higher lytic virus activity was recorded in the more productive sub-Antarctic zone than in the iron-limited waters of the Antarctic Circumpolar Current during two transects. Reduced lytic viral activity in the Antarctic Circumpolar Current was combined with a shift toward lysogenic infection, probably resulting from the lower concentration of potential prokaryotic hosts. Superimposed on this variation, lytic viral production was lower in a transect completed in the Drake Passage in autumn (1.8 × 10(8) to 1.5 × 10(9) liter(-1) day(-1)) than over the Greenwich Meridian during summer (5.1 × 10(8) to 2.0 × 10(10) cells liter(-1) day(-1)), indicating that viral activity is linked to the overall seasonal fluctuations in biotic activity. Interestingly, while prokaryotic abundance was lowest in the coastal Weddell Sea, levels of bacterial and lytic viral production (4.3 × 10(8) to 1.7 × 10(10) cells liter(-1) day(-1)) in this area were similar to those of the other zones. This may explain the weak relationship between the distribution of prokaryotes and chlorophyll in the Weddell Sea, as a high turnover of prokaryotic biomass may have been stimulated by the availability of substrates in the form of viral lysate. With estimated carbon and iron releases of 0.02 to 7.5 μg liter(-1) day(-1) and 1.5 to 175.7 pg liter(-1) day(-1), respectively, viral activity in the Southern Ocean is shown to be a major contributor to satisfying the elemental requirements of microbes, notably prokaryotes in the Weddell Sea and phytoplankton in the sub-Antarctic zone.
在贯穿南大洋的各个站点，从亚南极区到南极绕极流，再到一个南极大陆海域，研究了裂解和溶原性病毒感染。在两次横切过程中，在生产力更高的亚南极区记录到的裂解病毒活性高于铁限制的南极绕极流水域。南极绕极流中的裂解病毒活性降低，同时转向溶原性感染，这可能是由于潜在的原核宿主浓度降低所致。在此变化的基础上，在秋季德雷克海峡的横切过程中，裂解病毒的产生量较低（1.8×10^8 到 1.5×10^9 升^-1 天^-1），而在夏季格林威治子午线的产生量较高（5.1×10^8 到 2.0×10^10 个细胞升^-1 天^-1），这表明病毒活性与生物活性的整体季节性波动有关。有趣的是，虽然在沿海威德尔海原核生物丰度最低，但该区域的细菌和裂解病毒的产生量（4.3×10^8 到 1.7×10^10 个细胞升^-1 天^-1）与其他区域相似。这可能解释了威德尔海原核生物和叶绿素分布之间的弱相关性，因为病毒裂解物形式的底物的可用性可能刺激了原核生物生物量的高周转率。病毒活性在南大洋中的碳和铁的释放量估计分别为 0.02 到 7.5 μg 升^-1 天^-1 和 1.5 到 175.7 pg 升^-1 天^-1，表明它是满足微生物，特别是威德尔海的原核生物和亚南极区浮游植物的元素需求的主要因素之一。
