Skip to main content
. 2002 Sep 12;99(20):12703–12708. doi: 10.1073/pnas.202471499

Figure 1.

Figure 1

Organization of T7 gene 4 protein. Gene 4 protein consists of a primase and a helicase domain, connected by a linker region. The primase domain contains two subdomains: a zinc motif and a catalytic core. The gene 4 proteins used in this study are schematically presented. A 63-kDa protein; 56-kDa protein, a truncated gene 4 protein that lacks the N-terminal 63-aa residue containing the zinc motif; gp4-K122A, a gene 4 protein in which K122 at the catalytic site is replaced by alanine; PF, a primase fragment that contains only the primase domain from amino acid 1 to 271; and PF-K122A, a primase fragment in which K122 is replaced by alanine. Signs next to the abbreviated protein names denote the ability to catalyze the synthesis of primers.