NhaD family

The NhaD family (TC# 2.A.62) belongs to the Ion Transporter (IT) Superfamily.[1] A representative list of proteins belonging to the NhaD family can be found in the Transporter Classification Database.

The NhaD Na⁺/H⁺ antiporter has been characterized from two Vibrio species: V. parahaemolyticus and V. cholerae and in the haloalkaliphile, Alkalimonas amylolytica.[2][3] These proteins and their homologues are 400-500 aas long and exhibit 10-13 TMSs. They catalyze Na⁺/H⁺ and Li⁺/H⁺ antiport. They exhibit activity at basic pH (8-10) with no activity at pH 7.5. The Amylolytica antiporter has low Na⁺ affinity and has optimal activity at 600 mM Na⁺. Homologues are found in proteobacteria of all groups, Flavobacteria and Chlamydia. Distant homologues of the IT superfamily are ubiquitous.

The generalized reaction catalyzed by NhaD is:

nH⁺ (in) + mNa⁺ (out) ⇌ nH⁺ (out) + mNa⁺ (in).

See also

• Sodium-Proton antiporter
• Antiporter
• Transporter Classification Database

Further reading

• Barrero-Gil, Javier; Rodríguez-Navarro, Alonso; Benito, Begoña (2007-01-01). "Cloning of the PpNHAD1 transporter of Physcomitrella patens, a chloroplast transporter highly conserved in photosynthetic eukaryotic organisms". Journal of Experimental Botany 58(11): 2839–2849. doi:10.1093/jxb/erm094. ISSN 0022-0957. PMID 17617660.
• Kurz, Matthias; Brünig, Anika N. S.; Galinski, Erwin A. (2006-01-01). "NhaD type sodium/proton-antiporter of Halomonas elongata: a salt stress response mechanism in marine habitats?". Saline Systems 2: 10.doi:10.1186/1746-1448-2-10. ISSN 1746-1448.PMC 1552076. PMID 16872527.
• Liu, Jun; Xue, Yanfen; Wang, Quanhui; Wei, Yi; Swartz, Talia H.; Hicks, David B.; Ito, Masahiro; Ma, Yanhe; Krulwich, Terry A. (2005-11-01). "The activity profile of the NhaD-type Na+(Li+)/H+ antiporter from the soda Lake Haloalkaliphile Alkalimonas amylolytica is adaptive for the extreme environment". Journal of Bacteriology 187 (22): 7589–7595.doi:10.1128/JB.187.22.7589-7595.2005. ISSN 0021-9193.
• Melo, Ana M. P.; Felix, Nuno A. M.; Carita, João N.; Saraiva, Lígia M.; Teixeira, Miguel (2006-09-29)."The Na+/H+ antiporter of the thermohalophilic bacterium Rhodothermus marinus". Biochemical and Biophysical Research Communications 348 (3): 1011–1017.doi:10.1016/j.bbrc.2006.07.134. ISSN 0006-291X.PMID 16904646.
• Zhong, Nai-Qin; Han, Li-Bo; Wu, Xiao-Min; Wang, Li-Li; Wang, Fang; Ma, Yan-He; Xia, Gui-Xian (2012-06-01). "Ectopic expression of a bacterium NhaD-type Na+/H+ antiporter leads to increased tolerance to combined salt/alkali stresses". Journal of Integrative Plant Biology 54 (6): 412–421. doi:10.1111/j.1744-7909.2012.01129.x. ISSN 1744-7909. PMID 22583823.

References

1. Prakash, Shraddha; Cooper, Garret; Singhi, Soumya; Saier, Milton H. (2003-12-03). "The ion transporter superfamily". Biochimica et Biophysica Acta (BBA) - Biomembranes. 1618 (1): 79–92. doi:10.1016/j.bbamem.2003.10.010. ISSN 0006-3002. PMID 14643936.
2. Nozaki, K.; Kuroda, T.; Mizushima, T.; Tsuchiya, T. (1998-03-02). "A new Na+/H+ antiporter, NhaD, of Vibrio parahaemolyticus". Biochimica et Biophysica Acta (BBA) - Biomembranes. 1369 (2): 213–220. doi:10.1016/s0005-2736(97)00223-x. ISSN 0006-3002. PMID 9518619.
3. Ostroumov, Elena; Dzioba, Judith; Loewen, Peter C.; Dibrov, Pavel (2002-08-19). "Asp(344) and Thr(345) are critical for cation exchange mediated by NhaD, Na(+)/H(+) antiporter of Vibrio cholerae". Biochimica et Biophysica Acta. 1564 (1): 99–106. doi:10.1016/s0005-2736(02)00407-8. ISSN 0006-3002. PMID 12101001.

As of this edit, this article uses content from "2.A.62 The NhaD Na+:H+ Antiporter (NhaD) Family", which is licensed in a way that permits reuse under the Creative Commons Attribution-ShareAlike 3.0 Unported License, but not under the GFDL. All relevant terms must be followed.