The C. glutamicum 2262 pknG mutant also produces glutamate at a 40% higher specific rate compared with wild-type (Boulahya et al. [2010]).
This organism produces ethanol at a high yield (higher than 0.45 g g-1 at optimal conditions) and a high specific rate (up to 1.3 g g-1 cell mass h-1 [ 73]).
As a candidate bio-ethanol producer, Zymomonas mobilis showed some advantages, for example, higher specific rate of sugar uptake, high ethanol yield, lower biomass production, non-requirement of controlled addition of oxygen during fermentation, et cetera [ 8- 13].
Using this strain, we have developed the first industrial S. cerevisiae strain that converts D-xylose to ethanol with a yield close to the theoretical maximum yield and with a very high specific rate of fermentation.
However, wild-type Saccharomyces cerevisiae, which is the most commonly used yeast in ethanol fermentation due to its attractive properties, such as high yield of ethanol, high specific rate of fermentation [ 5], and its high tolerance to the end product, ethanol [ 6], is not able to metabolize xylose.
Supported Co catalysts with high specific rates require the synthesis of small metal crystallites at high local surface densities on support and the use of supports or alloys that increase the rate per surface Co (turnover rate).
When examining the batch tests where N2O an ({text{NO}}_{3}^) were both supplied as electron acceptors, the results suggest that N2O was being reduced concurrently with ({text{NO}}_{3}^), leading to higher specific rates of donor utilization.
Therefore, the PC3 reached the highest specific growth rate (0.033 day−1), whereas the CKs with the negative specific growth rate (−0.14 day−0.14
