T4 genes in the marine ecosystem: studies of the T4-like cyanophages and their role in marine ecology.
T4 genes in the marine ecosystem: studies of the T4-like cyanophages and their role in marine ecology.
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DOI：
10.1186/1743-422x-7-291
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发表时间：
2010-10-28
期刊：
影响因子：
4.8
通讯作者：
Mann NH
中科院分区：
文献类型：
--
作者：
Clokie MR;Millard AD;Mann NH
从基因组测序中可以明显看出，能够感染聚球藻和原氯球菌属的单细胞蓝藻的海洋蓝藻病毒不仅在形态上与T4相似，而且在基因上也是相关的，通常有大约40-48个基因。到目前为止，这些共同基因中的绝大多数在所有海洋蓝肌病毒中都是相同的。鉴于海洋单细胞蓝藻和类T4噬菌体异养宿主之间的基本生理差异，对蓝肌病毒的研究揭示了噬菌体-宿主关系的新颖而有趣的方面也就不足为奇了。海洋蓝肌病毒最有趣的特征之一是它们拥有许多明显来自宿主的基因，比如那些参与光合作用的基因，比如编码光系统II反应中心核心成分的PSBA基因。其他宿主来源的基因编码与碳代谢、磷酸盐获取和ppGpp代谢有关的酶。这些宿主衍生基因对噬菌体适合性的影响在很大程度上仍有待评估，这是实验室研究这组T4类噬菌体最重要的课题之一。然而，由于这些噬菌体对海洋初级生产的主要贡献者的影响，它们也具有相当大的环境意义，这种影响的真实程度和性质仍有待准确评估。
From genomic sequencing it has become apparent that the marine cyanomyoviruses capable of infecting strains of unicellular cyanobacteria assigned to the genera Synechococcus and Prochlorococcus are not only morphologically similar to T4, but are also genetically related, typically sharing some 40-48 genes. The large majority of these common genes are the same in all marine cyanomyoviruses so far characterized. Given the fundamental physiological differences between marine unicellular cyanobacteria and heterotrophic hosts of T4-like phages it is not surprising that the study of cyanomyoviruses has revealed novel and fascinating facets of the phage-host relationship. One of the most interesting features of the marine cyanomyoviruses is their possession of a number of genes that are clearly of host origin such as those involved in photosynthesis, like the psbA gene that encodes a core component of the photosystem II reaction centre. Other host-derived genes encode enzymes involved in carbon metabolism, phosphate acquisition and ppGpp metabolism. The impact of these host-derived genes on phage fitness has still largely to be assessed and represents one of the most important topics in the study of this group of T4-like phages in the laboratory. However, these phages are also of considerable environmental significance by virtue of their impact on key contributors to oceanic primary production and the true extent and nature of this impact has still to be accurately assessed.