Table 1

Mutagenesis studies on CDF members

Prokaryotic members

Eukaryotic member


RmCzcD

EcZitB

EcFieF

PtdMTP1


Topological position

AA substitution

Phenotype

AA substitution

Phenotype

AA substitution

Phenotype

AA substitution

Phenotype


N ter

C30S

Partially activee

N ter

C35S

No functione

N ter

C64S

Partially activee

N ter

H5R

Partially activea

N ter

H7R

No functiona

N ter

H9R

Partially activea

TMD I

E31D

Partially activea

E35D

Partially activeb

TMD I

E35A

Partially activeb

TMD I

E31K

No functiona

TMD II

D50E

Partially activea

TMD II

D50A

No functiona

D86A

No functionf

TMD II

D45C

Wild typec

TMD II

H49R

Not expresseda

H53R

No functiona

H89K

No functionf

TMD II

H49A

No functiona

H89A

No functionf

TMD II

M5OL

Hypersensitivea

M54L

Partially activea

TMD II

D49C

Wild typec

TMD II

D53E

Hypersensitivea

TMD II

D53A

Hypersensitivea

D57A

No functiona

D49A

No functionc

D93A

No functionf

TMD II

D53N

Hypersensitivea

TMDs II-III loop

G118A

No functione

TMD IV

N135A

No functiona

TMD V

H153C

Partially activec

TMD V

E154D

No functiona

H159E

No functiona

H260D

No functione

TMD V

E154N

No functiona

H159R

No functiona

TMD V

D157C

Partially actived

TMD V

D158E

No functiona

D163E

No functiona

D264E

No functione

TMD V

D158A

No functiona

D163A

No functiona

D157A

No functiond

D264A

No functione

TMD V

S167A

No functiona

W182L

Partially activea

TMD VI

D181A

Partially activea

D186A

No functiona

D288A

No functione

TMD VI

D181E

Hypersensitivea

D186E

Partially activea

D288E

No functione

TMD VI

D181N

Hypersensitivea

C ter

C291S

Wild typee

C ter

E214A

No functiona

C ter

H237R

No functiona

C ter

H251A

Partially activea

C ter

W245L

Partially activea

C ter

G248T

Partially activeb

C ter

C357S

Wild typee

C ter

H280A

No functiona

C ter

H298A

No functiona

C ter

C290S

Hypersensitivea

C294S

Wild typea


The results of site-directed mutagenesis analyses carried out on four CDF transporters ([14, 23, 29-31] and present study) are reported with the corresponding topological position. RmCzcD: Zn-CDF from C. metallidurans; EcZitB: Zn-CDF from E. coli; EcFieF: Fe/Zn-CDF from E. coli; PtdMTP1: Zn-CDF from P. trichocarpa × deltoides. "no function": the amino acid substitution led to the loss of any detectable function in the complementation test, comparable with the empty vector; "hypersensitive": the amino acid substitution resulted in a more sensitive phenotype, compared with the empty vector-transformed cells; "partially active": the phenotype is intermediate between the empty vector- and the wild type gene-transformed cells. EcFieF metal coordination residues [31] and the corresponding amino acids in the other transporters are in bold. References: a, [29]; b, [30]; c, [31]; d, [14]; e, this study; f, [23].

Montanini et al. BMC Genomics 2007 8:107   doi:10.1186/1471-2164-8-107

Open Data