The Manganese (Mn2+) Exporter (MntP) Family (TC# 2.A.107) is a member of the Lysine Exporter (LysE) Superfamily.[1] The MntP family is a small family whose members have been found in bacteria and archaea. MntP proteins are of about 200 amino acyl residues with 6 putative transmembrane segments (TMSs). The Conserved Domain Database (CDD) recognized two DUF204 repeats, each repeat having 3 TMSs. A representative list of proteins belonging to the MntP family can be found in the Transporter Classification Database.
Function
At least one member (YebN of E. coli, TC# 2.A.107.1.1) has been shown to function as a putative manganese efflux pump. Manganese sensitivity and intracellular manganese levels significantly increased in bacteria when the mntP (formerly yebN) gene, which encodes the MntP efflux pump, was deleted. While manganese is a highly important trace nutrient for organisms from bacteria to humans, acting as an important element in the defense against oxidative stress and as an enzyme cofactor, it becomes toxic when present in excess.[2]
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Jensen AN, Jensen LT (2014). "Chapter 1: Manganese Transport, Trafficking and Function in Invertebrates". In Costa L, Aschner M (eds.). Manganese in Health and Disease. Issues in Toxicology. Royal Society of Chemistry. pp. 1–33. doi:10.1039/9781782622383-00001. ISBN978-1-84973-943-6.