2.A.10 The 2-Keto-3-Deoxygluconate Transporter (KdgT) Family

The KdgT permease of Erwinia chrysanthemi is the only well-characterized member of the KdgT family although homologues are present in many bacteria.  Thus, members of the family are present both in Gram-negative and Gram-positive bacteria (Allen et al. 1989). The protein from E. chrysanthemi possesses 398 amino acids and probably traverses the membrane as α-helicies 10-12 times. Uptake is energized by proton symport (Condemine and Robert-Baudouy 1987).

The transport reaction catalyzed by KdgT is:

KDG (out) + H+ (out)  KDG (in) + H+ (in)

This family belongs to the BART Superfamily.



Allen, C., S. Reverchon, and J. Robert-Baudouy. (1989). Nucleotide sequence of the Erwinia chrysanthemi gene encoding 2-keto-3-deoxygluconate permease. Gene 83: 233-241.

Condemine, G. and J. Robert-Baudouy. (1987). 2-keto-3-deoxygluconate transport system in Erwinia chrysanthemi. J. Bacteriol. 169: 1972-1978.

Luoto, H.H., E. Nordbo, A.M. Malinen, A.A. Baykov, and R. Lahti. (2015). Evolutionarily divergent, Na+-regulated H+-transporting membrane-bound pyrophosphatases. Biochem. J. 467: 281-291.

Mesbahi-Vasey, S., L. Veras, M. Yonkunas, J.W. Johnson, and M.G. Kurnikova. (2017). All atom NMDA receptor transmembrane domain model development and simulations in lipid bilayers and water. PLoS One 12: e0177686.

Pujic, P., R. Dervyn, A. Sorokin, and S.D. Ehrlich. (1998). The kdgRKAT operon of Bacillus subtilis: detection of the transcript and regulation by the kdgR and ccpA genes. Microbiology 144(Pt11): 3111-3118.


TC#NameOrganismal TypeExample

2-keto-3-deoxygluconate:proton symporter (Condemine and Robert-Baudouy 1987).


KdgT of Erwinia chrysanthemi


2-keto-3-deoxygluconate permease (KDG transporter), KdgT


KdgT of Escherichia coli


Probable galacturonate uptake porter of 330 aas and 10 TMSs (Pujic et al. 1998).

Probable galacturonate uptake porter of Bacillus subtilis


KdgT homologue of 315 aas and 10 TMSs.

KdgT homologue of Anaerococcus senegalensis


N-terminal KdgT domain with 10 TMS and a C-terminal N-acetyl transferase (NAT) domain.  462 aas total.

KdgT of Streptococcus pasteurianus


Putative 2-keto-3-deoxygluconate:proton symporter of 320 aas and 10 TMSs.  This protein shows significant sequence similarity to members of family 2.A.98 (the PSE Famiy).

UP of Gardnerella vaginalis


TC#NameOrganismal TypeExample

Mitochondrial carrier, AMC2 or MC4, of 540 aas and

AMC2 of Plasmodium falciparum


TC#NameOrganismal TypeExample