Table 1. Composition of the packaging reaction.
| Compositiona | Titer×103 TU/mlb | Activity (%) | |
| Complete reaction | 1,499±191 (5) | 100 | |
| -VP1 control | 0 (4) | 0 | |
| -DNA control | 0 (5) | 0 | |
| VP1-ΔC | 0 (2) | 0 | |
| Purified VLPs | 0 (5) | 0 | |
| Step A | -DTT | 2±1 (3) | 0.1 |
| -RNase | 41±29 (3) | 2.7 | |
| -DTT&RNase | 8±5 (3) | 0.5 | |
| Step B | -ATP (5 mM) | 780±228 (3) | 52.0 |
| -Mg++ (5 mM) | 784±131 (3) | 52.3 | |
| -Glycerol (8%) | 983±218 (3) | 65.5 | |
| 100 mM salt | 368±126 (3) | 24.5 | |
| Step C | pH 5.2 | 1,499±191 (5) | 100 |
| -Ca++ (1 mM), pH 5.2 | 1,519±204 (3) | 101 | |
| pH 7.0 | 556±115 (3) | 37.0 | |
| -Ca++ (1 mM), pH 7.0 | 835 (1) | 55.7 | |
| Time of DTT addition | at step A | 1,589±431 (5) | 100 |
| at step B | 342±211 (5) | 21.5 | |
| at step C | 25±21 (5) | 1.5 | |
| after step C | 10±7 (5) | 0.6 |
a
Final concentration of the reagents in the reaction mixture at each step is shown in parentheses.
b
Average±S.E. The titer is shown as luciferase transduction units. The number in parenthesis represents the number of repeated experiments.