FIG. 3.

Distinct molecular architectures of T4CP family members. T4CPs possess recognizable P-loop NTP binding domains but display considerable variation in NTDs and CTDs. The different types of T4CPs are listed at the left, with representatives of each type at the right. T4CPs are designated with the protein name or accession number, with a subscript identifying the species or plasmid origin, followed by the length in amino acid (aa) residues in parentheses. The domains are indicated with the following color scheme: tan, predicted TM helices; dark blue, P-loop domains; red, C-terminal extensions that are ancestrally unrelated to C termini of other T4CPs. Protein sequence analyses were performed by using the programs TMHMM (TM helix prediction), BLASTP (local alignment), and the NCBI conserved-domain search tool. Protein sequences were obtained from the GenBank database (NCBI), and accession numbers are presented in the legend of Fig. 2. TMD, TM domain.