The S-layer protein from Campylobacter rectus: sequence determination and function of the recombinant protein.
The gene encoding the crystalline surface layer (S-layer) protein from Campylobacter rectus, designated slp, was sequenced and the recombinant gene product was expressed in Escherichia coli. The gene consisted of 4086 nucleotides encoding a protein with 1361 amino acids. The N-terminal amino acid sequence revealed that Slp did not contain a signal sequence, but that the initial methionine residue was processed. The deduced amino acid sequence displayed some common characteristic features of S-layer proteins previously reported. A homology search showed a high similarity to the Campylobacter fetus S-layer proteins, especially in their N-terminus. The C-terminal third of Slp exhibited homology with the RTX toxins from Gram-negative bacteria via the region including the glycine-rich repeats. The Slp protein had the same N-terminal sequence as a 104-kDa cytotoxin isolated from the culture supernatants of C. rectus. However, neither native nor recombinant Slp showed cytotoxicity against HL-60 cells or human peripheral white blood cells. These data support the idea that the N-terminus acts as an anchor to the cell surface components and that the C-terminus is involved in the assembly and/or transport of the protein.
Department of Periodontology and Endodontology, Okayama University Dental School, Japan.
M
M
Miyamoto
H
H
Maeda
M
M
Kitanaka
S
S
Kokeguchi
S
S
Takashiba
Y
Y
Murayama
D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D001426:Bacterial Proteins; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism; D002167:Campylobacter / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002470:Cell Survival; D003603:Cytotoxins / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics; D018922:HL-60 Cells; D006801:Humans; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D017422:Sequence Analysis, DNA
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D003603:Cytotoxins; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; C055764:S-layer proteins; D002118:Calcium