TABLE 2.
Molecular and kinetic properties of purified AK from eubacteria and M. thermophila
| Organism | Molecular massa (kDa)
|
Apparent Kmb (mM)
|
Reference(s) | ||||
|---|---|---|---|---|---|---|---|
| Native enzyme | Subunit | Acetate | ATP | Ac-P | ADP | ||
| Thermotoga maritima | 90 (α2) | 44 | 40 | 0.7 | 0.44 | 3 | This work |
| Methanosarcina thermophila | 94 (α2) | 53 | 22 | 2.8 | — | — | 1 |
| Clostridium thermoaceticum | 60 (α) | — | 135 | 1.64c | — | — | 32 |
| Bacillus stearothermophilus | 160 (α4) | 43 | 120 | 1.2 | 2.3 | 0.8 | 24 |
| Escherichia coli | 70 (α2) | 40 | 7 | 0.07 | 0.16 | 0.5 | 13 |
| Salmonella typhimurium | 70 (α2) | 40 | 7 | 0.07 | 0.16 | 0.5 | 13 |
| Rhodopseudomonas palustris | 47 (α2) | 45 | 40 | 1.1 | 0.0026 | 0.087 | 41 |
| Veillonella alcalescens | 88 (α2) | 42 | 170 | 10c | 5c | 1.3c | 4, 25 |
| Clostridium acetobutylicum | 78 (α2) | 42 | 160 | 2.5 | <1 | 6 | 10 |
| Acholeplasma laidlawii | 120–130 (α2) | 51 | 38.5d | 0.3d | 0.1d | 0.24d | 16 |
a
Molecular masses of native enzymes were determined by gel filtration, and those of subunits were determined by SDS-PAGE. The proposed subunit composition of the native enzyme is given in parentheses.
b
Ac, acetyl; P, phosphate; —, not determined.
c
Values to give half-maximal rates in sigmoidal reaction kinetics.
d
Values determined at low ionic strength.