Thöny B, Hwang D S, Fradkin L, Kornberg A
Department of Biochemistry, Stanford University School of Medicine, CA 94305-5307.
Proc Natl Acad Sci U S A. 1991 May 15;88(10):4066-70. doi: 10.1073/pnas.88.10.4066.
The gene encoding the protein that binds the three 13-mers in the origin (oriC) of Escherichia coli to block initiation of replication in vitro has been cloned, sequenced, and overexpressed. The gene possesses an open reading frame for 297 amino acids (mass of 33,471 Da). The protein has a motif for DNA-binding (helix-turn-helix) and has homology to a diverse set of prokaryotic regulatory proteins, known as the LysR family. The protein, previously referred to as the 33-kDa protein, has been named IciA (for inhibitor of chromosome initiation). The iciA gene is at 62.8 min on the chromosomal map. Cells with enhanced levels of the protein grow at a normal rate but generally exhibit a pronounced lag upon transfer to a fresh medium.
编码与大肠杆菌复制起点（oriC）中的三个13聚体结合以在体外阻断复制起始的蛋白质的基因已被克隆、测序并过量表达。该基因具有一个297个氨基酸的开放阅读框（质量为33471道尔顿）。该蛋白质具有一个DNA结合基序（螺旋-转角-螺旋），并且与多种原核调节蛋白具有同源性，这些蛋白被称为LysR家族。该蛋白质以前被称为33 kDa蛋白质，现已被命名为IciA（染色体起始抑制剂）。iciA基因位于染色体图谱的62.8分钟处。蛋白质水平增强的细胞以正常速率生长，但在转移到新鲜培养基后通常会表现出明显的延迟。
