Université Montpellier II UMR 5119 CNRS, IRD, IFREMER, CC 093, Place Eugène Bataillon, 34095 Montpellier cedex 5, France.
Microb Ecol. 2011 Oct;62(3):669-78. doi: 10.1007/s00248-011-9862-3. Epub 2011 May 10.
Culture studies of phage-host systems have shown that phage proliferation strongly depends on the physiological state of the host, but it is still unclear to what extent this holds true within aquatic ecosystems. We used a combination of flow sorting and electron microscopy to explore how the frequency of bacterial cells with attached viruses (FCAV), of visibly infected cells, and the number of intracellular viruses are distributed within five physiologic categories: cells with high (HNA) and low (LNA) nucleic acid content, with a compromised membrane, in division, and with an intact-looking morphology. FCAV was not different between the cellular physiologic categories, suggesting low influence of host physiology on viral adsorption. Infected cells were found within all the physiologic categories, besides the dividing cells, but showed different levels of new virion production, with the abundance of intracellular viruses ranked as follows: HNA > intact-looking cells > LNA > compromised membrane cells. These results favor the physiological control hypothesis of viral progeny production. The calculation of viral production rate of the HNA and LNA cells show that viral infection of HNA cells likely accounts for the majority of viral production. It also show that cells considered as less active can still act as resources for phages, although they contain much less intracellular phage particles.
噬菌体-宿主系统的培养研究表明，噬菌体的增殖强烈依赖于宿主的生理状态，但在水生生态系统中，这种依赖程度还不清楚。我们采用流式分选和电子显微镜相结合的方法，探究了附着病毒（FCAV）的细菌细胞频率、可见感染细胞的频率以及细胞内病毒数量在五个生理类别中的分布情况：高核酸含量（HNA）和低核酸含量（LNA）细胞、膜受损细胞、分裂细胞和形态完整的细胞。FCAV 在细胞生理类别之间没有差异，这表明宿主生理对病毒吸附的影响较小。除了分裂细胞外，感染细胞存在于所有生理类别中，但新病毒粒子的产生水平不同，细胞内病毒的丰度排序如下：HNA > 形态完整的细胞 > LNA > 膜受损细胞。这些结果支持病毒后代产生的生理控制假说。对 HNA 和 LNA 细胞的病毒产生率的计算表明，HNA 细胞的病毒感染可能占病毒产生的大部分。这也表明，虽然这些细胞内的噬菌体颗粒较少，但被认为不太活跃的细胞仍可作为噬菌体的资源。
