TABLE 2.
Properties of ALDH complexes purified from membranes of acetic acid bacteria
| Property | Findingsa for: |
||||||
|---|---|---|---|---|---|---|---|
| A. polyoxogenes | G. suboxydans | A. rances |
A. acetid |
Ga. europaeus | Ga. diazotrophicus | ||
| 1 | 2 | ||||||
| General features | |||||||
| Molecular mass (kDa) | 90 | 140 | 145 | 157 | 125 | ND | 129.7 |
| Subunit size (kDa) | 75, 19 | 86, 55 | 78, 66 | 75, 45, 14 | 125 | 79, 46, 17 | 79.7, 50 |
| Prosthetic groups | |||||||
| PQQ | YesA | YesA | YesA | YesA | ND | ND | 1BC |
| Heme C | NDD | 1DE | NDD | YesD | NDD | 3DF | 3DEF |
| Heme B | NDD | NDD | NDD | NDD | NDD | YesD | 1DG |
| [2Fe:2S] | ND | ND | ND | ND | ND | YesD | NDD |
| Molybdopterin | ND | ND | ND | ND | ND | YesH | ND |
| Catalytic properties | |||||||
| Aldehyde specificity | C2-C6 | C2-C6 | C2-C6 | C2-C6 | Broad | ND | C2-C6 |
| Optimal pHb | 7* | 4† | 5.1† | 5† | 8† | ND | 3.5†; 7* |
| Km (mM)c | 12 | 3.3 | 0.91 | 2.9 | 0.15 | 2.1 | 3.3 |
a
The source or reference(s) for the indicated strains were as follows: A. polyoxogenes(9), G. suboxydans (2, 5), A. rances (15), A. aceti (4, 5, 23), Ga. europaeus (29), and Ga. diazotrophicus (this study). ND, not determined or not detected. Determination methods are indicated by superscript capital letters as follows: A, fluorescence spectroscopy; B, HPLC; C, EPR; D, visible-light spectroscopy; E, redox titration; F, zymography; G, HPLC; H, deduced from amino acid sequence.
b
Electron acceptors: *, PMS plus DCPIP; †, ferricyanide.
c
Substrate: acetaldehyde.
d
Two ALDH complexes (1 and 2) have been purified from A. aceti.