Functional substitution of the transient membrane-anchor domain in Escherichia coli FtsY with an N-terminal hydrophobic segment of Streptomyces lividans FtsY.
FtsY is a signal recognition particle receptor in Escherichia coli that mediates the targeting of integral membrane proteins to translocons by interacting with both signal recognition particle (SRP)-nascent polypeptide-ribosome complexes and the cytoplasmic membrane. Genes encoding the N-terminal segments of Streptomyces lividans FtsY were fused to a gene encoding the E. coli FtsY NG domain (truncated versions of FtsY lacking the transient membrane-anchor domain at the N-terminus), introduced into a conditional ftsY-deletion mutant of E. coli, and expressed in trans to produce chimeric FtsY proteins. Under FtsY-depleted conditions, strains producing chimeric proteins including 34 N-terminal hydrophobic residues grew whereas strains producing chimeric proteins without these 34 residues did not. A strain producing the chimeric protein comprising the 34 residues and NG domain processed beta-lactamase, suggesting that the SRP-dependent membrane integration of leader peptidase was restored in this strain. These results suggest that the N-terminal hydrophobic segment of FtsY in this Gram-positive bacterium is responsible for its interaction with the cytoplasmic membrane.
Maeda
Isamu
I
Department of Bioproductive Science, Faculty of Agriculture, Utsunomiya University, Utsunomiya, Tochigi, Japan. i-maeda@cc.utsunomiya-u.ac.jp
Hirata
Asumi
A
Shoji
Miki
M
Ueda
Shunsaku
S
Yoshida
Kazuyuki
K
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development; D005816:Genetic Complementation Test; D057927:Hydrophobic and Hydrophilic Interactions; D017434:Protein Structure, Tertiary; D018160:Receptors, Cytoplasmic and Nuclear / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D048170:Streptomyces lividans / Q000235:genetics*
D001426:Bacterial Proteins; C087406:FtsY protein, Bacteria; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins