Table 5.
Counts of Mxa transport proteins according to substrate type
|
Substrate |
No. of proteins of indicated type acting on substrate type |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| Channels/Pores | Primary carriers | Secondary carriers | Group translocators | Transmembrane electron flow carriers | Auxiliary proteins | (Putative) Poorly characterized | Total no. of systems | ||
|
I. Inorganic molecules |
|
|
|
|
|
|
|
|
|
| A. |
Nonselective |
3 |
|
|
|
|
|
|
3 |
| B. |
Cations |
6 |
36 |
38 |
|
1 |
|
3 |
84 |
| C. |
Anions |
|
6 |
10 |
|
2 |
|
|
18 |
| D. |
Electrons |
|
4 |
|
|
3 |
|
|
7 |
|
II. Carbon sources |
|
|
|
|
|
|
|
|
|
| A. |
Sugars & polyols |
|
4 |
2 |
2 |
|
|
|
8 |
| B. |
Monocarboxylates |
|
|
|
|
|
|
|
0 |
| C. |
Di- & tricarboxylates |
|
|
1 |
|
|
|
|
1 |
| D. |
Organoanions (noncarboxylic) |
|
|
2 |
|
|
|
|
2 |
| E. |
Aromatic Compounds |
|
4 |
|
|
|
|
|
4 |
|
III. Amino acids & their derivatives |
|
|
|
|
|
|
|
|
|
| A. |
Amino acids & conjugates |
|
6 |
14 |
|
|
|
|
20 |
| B. |
Amines, amides, polyamines, & organocations |
1 |
|
|
|
|
|
|
1 |
| C. |
Peptides |
|
12 |
9 |
|
|
|
1 |
22 |
|
IV. Vitamins, cofactors & cofactor precursors |
|
|
|
|
|
|
|
|
|
| A. |
Vitamins & vitamin or cofactor precursors |
|
5 |
2 |
|
|
|
|
7 |
| B. |
Enzyme & redox cofactors |
|
1 |
|
|
|
|
|
1 |
| C. |
Siderophores; siderophore-Fe complexes |
|
2 |
1 |
|
|
|
|
3 |
| D. |
Nucleosides/nucleotides |
1 |
2 |
1 |
|
|
|
|
4 |
|
V. Drugs, dyes, sterols & toxins |
|
|
|
|
|
|
|
|
|
| A. |
Multiple drugs |
|
1 |
32 |
|
|
1 |
|
34 |
| B. |
Specific drugs |
|
11 |
2 |
|
|
|
|
13 |
| C. |
Pigments |
|
|
|
|
|
|
|
|
| D. |
Other hydrophobic substances |
|
|
5 |
|
|
|
|
5 |
| E. |
Toxins |
6 |
4 |
1 |
|
|
|
|
11 |
| F. |
Virulence factors |
|
|
|
|
|
|
2 |
2 |
|
VI. Macromolecules |
|
|
|
|
|
|
|
|
|
| A. |
Carbohydrates |
1 |
2 |
9 |
|
|
3 |
|
15 |
| B. |
Proteins |
2 |
19 |
1 |
|
|
4 |
|
26 |
| C. |
Lipids |
|
9 |
3 |
5 |
|
|
|
17 |
|
VII. Nucleic acids |
|
|
|
|
|
|
|
|
|
| A. |
Nucleic acids |
|
1 |
|
|
|
|
|
1 |
| |
|
|
|
|
|
|
|
|
|
|
VIII. Water |
|
|
|
|
|
|
|
|
|
| A. |
Water |
1 |
|
|
|
|
|
|
1 |
|
IX. Unknown |
|
|
|
|
|
|
|
|
|
| A. |
Unknown |
|
17 |
20 |
|
4 |
|
4 |
45 |
| Total | 21 | 146 | 153 | 7 | 10 | 8 | 10 | 355 | |
Substrate categories include: (I) inorganic molecules; (II) carbon sources; (III) amino acids & their derivatives; (IV) vitamins, cofactors & cofactor precursors; (V) drugs, dyes, sterols & toxins; (VI) macromolecules; (VII) nucleic acids; and (VIII) unknown.