Table 1. Half-lives of phospho-HHKs.

Proteins	Half-life (min)
CheA3∼P	31.2±2.2
CheA3:D663A∼P	79.6±2.5
CheS3∼P	55.4±6.1
CheS3:D54A∼P	>4 hours

Standard deviations were calculated from two replicate experiments for each protein.