Chaperone and antichaperone activities of trigger factor.
Reduced denatured lysozyme tends to aggregate at neutral pH and competition between productive folding and aggregation substantially reduces the efficiency of refolding. Trigger factor, a folding catalyst and chaperone can, depending on the concentration of trigger factor and the solution conditions, cause either a substantial increase (chaperone activity) or a substantial decrease (antichaperone activity) in the recovery of native lysozyme as compared with spontaneous refolding. When trigger factor is working as a chaperone, the reactivation rates of lysozyme are decelerated and aggregation decreases with increasing trigger factor concentrations. Under conditions where antichaperone activity of trigger factor dominates, the reactivation rates of lysozyme are accelerated and aggregation is increased. Trigger factor and lysozyme were both released from the aggregates on re-solubilization with urea indicating that trigger factor participates directly in aggregate formation and is incorporated into the aggregates. The apparently dual effect of trigger factor toward refolding of lysozyme is a consequence of the peptide binding ability and may be important in regulation of protein biosynthesis.
Huang
Guo-Chang
GC
National Laboratory of Biomacromolecules, Institute of Biophysics, Academia Sinica, Beijing, China.
Chen
Jia-Jia
JJ
Liu
Chuan-Peng
CP
Zhou
Jun-Mei
JM
D002021:Buffers; D029968:Escherichia coli Proteins / Q000378:metabolism*; D019855:Ethylene Glycol / Q000378:metabolism; D006531:HEPES; D018832:Molecular Chaperones / Q000378:metabolism*; D009113:Muramidase / Q000378:metabolism; D019696:Peptidylprolyl Isomerase / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism; D011489:Protein Denaturation; D017510:Protein Folding; D012965:Sodium Chloride / Q000378:metabolism
D002021:Buffers; D029968:Escherichia coli Proteins; D018832:Molecular Chaperones; D010710:Phosphates; D012965:Sodium Chloride; D009113:Muramidase; C403324:trigger factor, E coli; D019696:Peptidylprolyl Isomerase; D019855:Ethylene Glycol; D006531:HEPES