N-terminal methionine in recombinant proteins expressed in two different Escherichia coli strains.
Two genes coding for chloramphenicol acetyltransferase and human interferon gamma, respectively, were overexpressed constitutively in two different strains of Escherichia coli (E. coli LE392 and E. coli XL1). The N-terminal amino acid analysis of the purified proteins showed that: (a) the N-terminal methionine is processed more efficiently in E. coli LE392 rather than in E. coli XL1 cells; (b) the N-terminal methionine is removed better from the heterologous human interferon gamma in comparison with the homologous chloramphenicol acetyltransferase protein: and (c) there is no strong correlation between the efficiency of N-terminal procession and the yield of recombinant protein.
Vassileva-Atanassova
A
A
Institute of Molecular Biology, Bulgarian Academy of Science, Sofia, Bulgaria. anel@obzor.bio21.bas.bg
Mironova
R
R
Nacheva
G
G
Ivanov
I
I
D000595:Amino Acid Sequence; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism*; D008715:Methionine / Q000032:analysis / Q000378:metabolism*; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism
D011994:Recombinant Proteins; D007371:Interferon-gamma; D008715:Methionine; D015500:Chloramphenicol O-Acetyltransferase