Arnold E, Luo M, Vriend G, Rossmann M G, Palmenberg A C, Parks G D, Nicklin M J, Wimmer E
Proc Natl Acad Sci U S A. 1987 Jan;84(1):21-5. doi: 10.1073/pnas.84.1.21.
Mature picornaviral proteins are derived by progressive, posttranslational cleavage of a precursor polyprotein. These cleavages play a role in the control of virus functions. Although the processed termini are separated by as much as 75 A in the native virus capsid, the fold and arrangement of polypeptide chains in a protomer before proteolysis are likely to be similar to that found in the mature virus. The three-dimensional structures of rhinovirus and Mengo virus suggest that the cleavage sites within the protomeric precursor are in structurally flexible regions. The final proteolytic processing event, maturation of the virion peptide VP0 (also called peptide 1AB) appears to occur by an unusual autocatalytic serine protease-type mechanism possibly involving viral RNA basic groups that would serve as proton-abstractors during the cleavage reaction.
成熟的小核糖核酸病毒蛋白是由前体多蛋白经逐步的翻译后切割产生的。这些切割在病毒功能的控制中发挥作用。尽管在天然病毒衣壳中加工后的末端相隔多达75埃，但在蛋白水解之前原聚体中多肽链的折叠和排列可能与成熟病毒中的相似。鼻病毒和门戈病毒的三维结构表明，原聚体前体中的切割位点位于结构灵活的区域。病毒粒子肽VP0（也称为肽1AB）的最终蛋白水解加工事件似乎是通过一种不寻常的自催化丝氨酸蛋白酶型机制发生的，该机制可能涉及病毒RNA碱性基团，这些基团在切割反应中作为质子提取剂。
