Induction Evolution and Entropy of Bacteriophage λQ- Mutant in Escherichia coli

含噬菌λQ-變異株之大腸桿菌之誘導演化及亂度

陳博彥(Bor-Yann Chen)

《Journal of the Chinese Institute of Chemical Engineers》 32卷1期 (2001/01) Pp. 81-87

https://doi.org/10.6967/JCICE.200101.0081

摘要

本研究以生態觀點之「亂度」評估法來衡量噬菌體λ及大腸桿菌於「誘導」過程之「宿主-寄生蟲」消長現象。從誘導過程之鐘形「訊息亂度」之時間趨勢表示正向反應變異為「λ-阻抗」能力之宿主菌確實已發生，因為「再誘導」菌相細胞之「第二生長期」並未發生因「感染」而失去細胞存活之現象。而且，逆反應變異回原有菌相而成對噬菌體λ「敏感」及「阻抗」菌相共存之「最大分歧度」或回歸至起始單一對噬茵體λ敏感菌相並未曾演化發生。因此於平衡狀態下，物種之「基因多態性」並無法完成。此點明顯澄清修正過去研究部分假設結果。由於噬菌體λ之「減毒」相對亦加強各物種之全體存活，因此僅得到緩和程度之誘導結果。

並列摘要

The study provides an entropy assessment from an ecological perspective indicating parasite-host evolutions between bacteriophage λ and Escherichia coli during induction. The bell-shaped time course of the information entropy indicates that a forward mutation of ”λ-resistant” hosts takes place, since no loss of cellular viability occurs for the second growth phase of reinduced (i.e. recovered) cells. In addition, no back mutation to obtain a maximal complexity (i.e. λ-resistant and sensitive species coexistence) or original ecology (i.e. original λ-lysogen) for the evolution occurs. Thus, a genetic polymorphism of species in a balanced equilibrium cannot be established. This point obviously clarifies certain hypothesized results shown In previous work. In addition, virulence reduction of phage λ enhances total survival of host cells and parasitic λ species, thus a moderate induction performance is resulted.

並列關鍵字

Bacteriophage λ ； Temperature Induction ； Escherichia coli ； Information Entropy ； Virulence Reduction