Castillo F J, Bartell P F
J Virol. 1976 May;18(2):701-8. doi: 10.1128/JVI.18.2.701-708.1976.
The adsorption apparatus of phage 2 consits of a symmetrical base plate of snowflake appearance, composed of six droplike spikes 7.0 to 7.5 nm in length with a maximum diameter of 4.5 to 5.0 nm. The spikes are attached by their narrow ends to a central ring 7.0 to 7.5 nm in diameter. Phage 2 deopolymerase, a phage 2-induced hydrolytic enzyme, was found to be a structural protein of phage 2 or in close association with the base plate. Pdp1, a phage 2 mutant, possesses a polypeptide that is antigenically similar to the depolymerase, but devoid of hydrolytic activity. This polypeptide was found to be located in the region of the base plate of pdp1. Treatment of intact cells of strain BI with purified phage 2 depolymerase inhibited the adsorption of phage 2. When phage receptor-containing fractions of slime glycolipoprotein and lipopolysaccharide were hydrolyzed by the depolymerase, amino sugars were released, and the phage-inactivating activities of these fractions were lost. The depolymerase was also observed to induce the lysis of strain BI cells in hypotenic medium. The phage 2 depolymerase appears to play a role in adsorption and release of phage.
噬菌体2的吸附装置由雪花状的对称基板组成，该基板由六个长度为7.0至7.5纳米、最大直径为4.5至5.0纳米的水滴状刺突组成。这些刺突通过其狭窄的末端连接到一个直径为7.0至7.5纳米的中央环上。噬菌体2解聚酶是一种由噬菌体2诱导的水解酶，被发现是噬菌体2的一种结构蛋白或与基板紧密相关。Pdp1是噬菌体2的一个突变体，它拥有一种多肽，该多肽在抗原性上与解聚酶相似，但缺乏水解活性。这种多肽被发现位于pdp1基板区域。用纯化的噬菌体2解聚酶处理BI菌株的完整细胞可抑制噬菌体2的吸附。当解聚酶水解含有噬菌体受体的粘液糖脂和脂多糖组分时，氨基糖被释放，并且这些组分的噬菌体失活活性丧失。还观察到解聚酶在低渗培养基中诱导BI菌株细胞的裂解。噬菌体2解聚酶似乎在噬菌体的吸附和释放中起作用。
