摘要
在E.coli表达系统中,克隆的外源基因的表达水平往往有较大的差别。例如,Goeddel等构建的α干扰素克隆菌的产量达2.5×10~8u/l,而在Gray等构建的γ干扰素表达系统中,干扰素产量只有2.5×10~4u/l。这种差别及实际应用的要求推动了人们对影响外源基因表达的各个因素进行研究。过去几十年中,由于生物化学及分子生物学家们的努力,对E.coli内源基因表达调控的规律有了许多认识。目前在研究E.coli中克隆的外源基因的表达调控时,往往也是借鉴这方面的成果。 克隆菌E.coli MEC101(pBV37)含有一选择性标记Ap^r目的基因IFN,它们来源不同,就宿主而言分别属于内源基因和外源基因。本文就这两个基因的表达特性进行了研究和比较。
Ap gene at the plasmid pBV37 which could express human interferon a 1 was a homologous gene for the host strain, while IFN gene was a heterologous gene. These genes could express, β-lactamase and interferon respectively. In terms of total activity ,β-lactamase had a same trend as IFN. However,there was a distinction between their specific activities. The specific activity of β-lactamase decreased with the time, while that of IFN incerased. Some possible mechanisms and the possibility for excluding the structural instability of plasmid were proposed.
出处
《工业微生物》
CAS
CSCD
北大核心
1994年第3期1-6,共6页
Industrial Microbiology
关键词
干扰素
克隆菌
基因表达
大肠杆菌
Interferon, β-lactamase, Homologous and heterologous genes,Gene expression, Instability of plasm id
