Table 1 Averaged metrics characterizing the packaging dynamics.

From: Single-molecule measurements of bacteriophage lambda DNA packaging using purified terminase motor proteins and E. coli integration host factor

Packaging Metrics—Mean values (SD) [SEM]

Sample

Packaging rate (bp/s)

Motor velocity (bp/s)

Pause frequency (#/kbp)

Initiation time (s)

Pause duration (s)

Packaging detection efficiency

Extract (25)

460 (291) [6.3]

514 (264) [6.1]

0.37 (1.1) [0.22]

31 (39) [6.7]

0.55 (0.9) [0.14]

38%

Pure 1 (30)

n/a

n/a

n/a

n/a

n/a

0%

Pure 1 + IHF (13)

477 (198) [6.4]

510 (199) [6.2]

0.28 (0.45) [0.12]

59 (69) [21]

0.25 (0.28) [0.07]

43%

Pure 2 (30)

n/a

n/a

n/a

n/a

n/a

0%

Pure 2 + IHF (23)

470 (240) [7.1]

504 (221) [6.8]

0.43 (0.5) [0.13]

55 (91) [23]

0.40 (0.41) [0.08]

40%

  1. Measurements were taken with 0.5 mM ATP and 5 pN applied force using the indicated terminase samples. The number in parentheses next to the sample name indicates the number of recorded packaging events (or number of tethers in the experiments without IHF). Packaging rate refers to the DNA translocation velocity including pauses whereas the motor velocity excludes pauses. The standard deviation in the values is indicated in parentheses “()”, and the standard error in the mean is indicated in brackets “[]”. Packaging rate and motor velocity are averaged over 1 s time intervals and the pause frequency and initiation time are averaged over individual packaging events. No packaging was measured for the “Pure 1” and “Pure 2” samples without IHF.
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