Backhaus H
J Virol. 1985 Aug;55(2):458-65. doi: 10.1128/JVI.55.2.458-465.1985.
DNA packaging of Salmonella phage P22 starts at a defined site on a concatemer of P22 genomes. The molecular ends formed at the packaging initiation site (pac) map within a region of ca. 120 base pairs and may contain any of the four nucleotides at their 5' end. The determination of the positions of the cuts within the sequence demonstrates a characteristic distribution of cut sites which apparently cannot be attributed to the sequence organization of the involved regions. Symmetric elements of the sequence might serve as signals for a recognition event(s) at pac in a separate process preceding the cutting reaction. The region of packaging initiation is located within the sequence coding for gene 3. The 3 protein is responsible for the site specificity of this process. We find no significant homology to Nu1 protein, which appears to have an analogous or similar function in the DNA maturation of Escherichia coli phage lambda.
沙门氏菌噬菌体P22的DNA包装起始于P22基因组串联体上的一个特定位点。在包装起始位点（pac）形成的分子末端定位在约120个碱基对的区域内，其5'端可能包含四种核苷酸中的任何一种。序列中切割位点位置的确定显示出切割位点的特征性分布，这显然不能归因于所涉及区域的序列组织。该序列的对称元件可能在切割反应之前的一个独立过程中作为pac处识别事件的信号。包装起始区域位于编码基因3的序列内。3蛋白负责该过程的位点特异性。我们发现它与Nu1蛋白没有明显的同源性，Nu1蛋白在大肠杆菌噬菌体λ的DNA成熟过程中似乎具有类似或相似的功能。
