TY - JOUR
T1 - Cyclic enterobacterial common antigen
T2 - Potential contaminant of bacterially expressed protein preparations
AU - Erbel, Paul J A
AU - Seidel, Ronald
AU - Macintosh, Scott E.
AU - Gentile, Lisa N.
AU - Amor, Juan C.
AU - Kahn, Richard A.
AU - Prestegard, James H.
AU - McIntosh, Lawrence P.
AU - Gardner, Kevin H.
N1 - Funding Information:
We thank Dr Paul Rick (USUHS) for graciously sharing his expertise regarding ECA biosynthesis. This work was supported by the National Institutes of Health (GM61268 to RAK and JHP; CA95471 to KHG), the Robert A. Welch Foundation (I-1424 to KHG) and the National Cancer Institute of Canada (LPM) with funds from the Canadian Cancer Society and instrument support from the Protein Engineering Network of Centres of Excellence (to L.P.M.). L.P.M. is a CIHR Scientist.
PY - 2004/6
Y1 - 2004/6
N2 - We have previously reported the identification of the cyclic enterobacterial common antigen (ECACYC) polysaccharide in E. coli strains commonly used for heterologous protein expression (PJA Erbel et al., J. Bacteriol. 185 (2003): 1995). Following this initial report, interactions among several NMR groups established that characteristic N-acetyl signals of ECACYC have been observed in 15N-1H HSQC spectra of samples of various bacterially-expressed proteins suggesting that this water-soluble carbohydrate is a common contaminant. We provide NMR spectroscopic tools to recognize ECACYC in protein samples, as well as several methods to remove this contaminant. Early recognition of ECA-based NMR signals will prevent time-consuming analyses of this copurifying carbohydrate.
AB - We have previously reported the identification of the cyclic enterobacterial common antigen (ECACYC) polysaccharide in E. coli strains commonly used for heterologous protein expression (PJA Erbel et al., J. Bacteriol. 185 (2003): 1995). Following this initial report, interactions among several NMR groups established that characteristic N-acetyl signals of ECACYC have been observed in 15N-1H HSQC spectra of samples of various bacterially-expressed proteins suggesting that this water-soluble carbohydrate is a common contaminant. We provide NMR spectroscopic tools to recognize ECACYC in protein samples, as well as several methods to remove this contaminant. Early recognition of ECA-based NMR signals will prevent time-consuming analyses of this copurifying carbohydrate.
KW - Enterobacterial common antigen
KW - Heterologous protein expression
KW - N-acetylated carbohydrate
KW - Protein purification
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U2 - 10.1023/B:JNMR.0000019252.65073.24
DO - 10.1023/B:JNMR.0000019252.65073.24
M3 - Article
C2 - 15014233
AN - SCOPUS:1842607683
SN - 0925-2738
VL - 29
SP - 199
EP - 204
JO - Journal of biomolecular NMR
JF - Journal of biomolecular NMR
IS - 2
ER -