The crystal structure of leucyl/phenylalanyl-tRNA-protein transferase from Escherichia coli.
Leucyl/phenylalanyl-tRNA-protein transferase (L/F-transferase) is an N-end rule pathway enzyme, which catalyzes the transfer of Leu and Phe from aminoacyl-tRNAs to exposed N-terminal Arg or Lys residues of acceptor proteins. Here, we report the 1.6 A resolution crystal structure of L/F-transferase (JW0868) from Escherichia coli, the first three-dimensional structure of an L/F-transferase. The L/F-transferase adopts a monomeric structure consisting of two domains that form a bilobate molecule. The N-terminal domain forms a small lobe with a novel fold. The large C-terminal domain has a highly conserved fold, which is observed in the GCN5-related N-acetyltransferase (GNAT) family. Most of the conserved residues of L/F-transferase reside in the central cavity, which exists at the interface between the N-terminal and C-terminal domains. A comparison of the structures of L/F-transferase and the bacterial peptidoglycan synthase FemX, indicated a structural homology in the C-terminal domain, and a similar domain interface region. Although the peptidyltransferase function is shared between the two proteins, the enzymatic mechanism would differ. The conserved residues in the central cavity of L/F-transferase suggest that this region is important for the enzyme catalysis.
Dong
Xuesong
X
RIKEN Genomic Sciences Center, Tsurumi, Yokohama 230-0045, Japan.
Kato-Murayama
Miyuki
M
Muramatsu
Tomonari
T
Mori
Hirotada
H
Shirouzu
Mikako
M
Bessho
Yoshitaka
Y
Yokoyama
Shigeyuki
S
D000595:Amino Acid Sequence; D019881:Aminoacyltransferases / Q000737:chemistry*; D020134:Catalytic Domain; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D029968:Escherichia coli Proteins / Q000737:chemistry*; D008969:Molecular Sequence Data; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D016415:Sequence Alignment
D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; D019881:Aminoacyltransferases; C021511:leucyltransferase