Table 2.
Proportion of heterotrimers in renatured mixtures
| 1:1 | 1:2 | 2:1 | |
|---|---|---|---|
| PII:GlnK mixture | |||
| GlnK3 (%) | 12 (12) | 28 (30) | 6 (4) |
| PII1GlnK2 (%) | 34 (37) | 40 (44) | 18 (22) |
| PII2GlnK1 (%) | 43 (37) | 27 (22) | 47 (44) |
| PII3 (%) | 11 (12) | 5 (4) | 29 (30) |
| PII-UMP:GlnK-UMP mixture | |||
| GlnK-UMP3, % | 30 | 45 | 16 |
| PII-UMP1GlnK-UMP2, % | 28 | 27 | 24 |
| PII-UMP2GlnK-UMP1, % | 29 | 20 | 35 |
| PII-UMP3, % | 13 | 8 | 25 |
| PII-UMP:GlnK mixture | |||
| GlnK3, % | 14 | 22 | 5 |
| PII-UMP1GlnK2, % | 34 | 34 | 16 |
| PII-UMP2GlnK1, % | 41 | 35 | 46 |
| PII-UMP3, % | 11 | 9 | 33 |
Proportions of various species separated on native 8% polyacrylamide gel were quantified as in Materials and Methods. In PII:GlnK section, between parentheses, the theoretical fractions expected for an unbiased binomial distribution are given. The same numbers should have applied to the PII-UMP:GlnK-UMP section had their distributions been unbiased. In this section, the bias observed is slight and in favor of a stronger attractive interaction between uridylylated GlnKs than between uridylylated PIIs. The PII-UMP:GlnK section also shows a distribution close to the theoretically expected values.