1

NRT1.1

/H⁺ symport

[75] [161]

2

NRT1.2

/H⁺ symport

[157]

3

NRT2.1

/H⁺ symport

[159]

4

NRT2.2

/H⁺ symport

[232]

5

NRT2.4

/H⁺ symport

[227]

6

AMT1.1

uniporters/NH₃/H⁺ co-transporters

[59]

7

AMT1.2

uniporters/NH₃/H⁺ co-transporters

[170]

8

AMT1.3

uniporters/NH₃/H⁺ coransporters

[162]

9

AMT1.5

uniporters/NH₃/H⁺ coransporters

[162]

10

AMT2.1

uniporters/NH₃/H⁺ coransporters

[171]

11

AMT5.1

uniporters/NH₃/H⁺ coransporters

[167]

12

DUR3

Urea/H⁺symport

[158] [165]

13

NIP

Urea transport through a channel

[191]