TABLE 2.
PDH mRNA, transcription, and protein levels in aerobically and anaerobically grown E. coli wild-type strain W3110 and ethanologenic mutant strain SE2378
| Strain | Relative mRNA levela
|
β-Galactosidase activityb
|
PDH activityc
|
|||
|---|---|---|---|---|---|---|
| With O2 | Without O2 | With O2 | Without O2 | With O2 | Without O2 | |
| W3110 | 1.00 | 0.98 | 600 | 630 | 370 | 185 |
| SE2378 | 0.71 | 0.77 | 570 | 680 | 240 | 200 |
a
Relative mRNA levels were determined by quantitative RT-PCR. The level of aceE mRNA in wild-type strain W3110 grown under aerobic conditions was defined as 1.0, and the relative levels of aceE mRNA for the other growth conditions and strain SE2378 were determined.
b
β-Galactosidase activities of Ppdh-lacZ fusions using λYK1 and λYK2 at λatt are expressed in nmol·min−1·mg protein−1.
c
The PDH activity is the PDH (E1) activity of the PDH complex and is expressed in nmol ferricyanide reduced·min−1·mg protein−1. See Materials and Methods for other details.