Ll. Randall et Sjs. Hardy, HIGH SELECTIVITY WITH LOW SPECIFICITY - HOW SECB HAS SOLVED THE PARADOX OF CHAPERONE BINDING, Trends in biochemical sciences, 20(2), 1995, pp. 65-70
Fundamental to the function of all molecular chaperones is their amazi
ng ability to selectively and rapidly bind proteins in non-native stat
es. Chaperones modulate a kinetic partitioning among the alternative p
athways open to polypeptides within a cell, so that the proper pathway
is taken. Here we review studies of SecB, a chaperone in Escherichia
coli dedicated to facilitation of protein export, and emphasize the fe
atures that enable it to bind rapidly with high affinity and selectivi
ty in the absence of consensus in sequence. The concepts discussed are
likely to be generally applicable to chaperones.