ABC	ATP-binding cassette
CAX	cation/H+ antiporters
CET	cation-efflux transporter
HAD	Haloacid dehalogenase
HMA	Heavy metal ATPase
IRT	iron transporter
LCT	low-affinity cation transporter
MBD	metal binding domains
MTP	metal tolerance protein
NRAMP	natural resistance associated macrophage protein
ZIP	Zn-regulated transporter-like protein
NJ	Neighbor-joining