A novel heavy metal ATPase peptide from Prosopis juliflora is involved in metal uptake in yeast and tobacco

Abstract

Heavy metal pollution of agricultural soils is one of the most severe ecological problems in the world. Prosopis juliflora, a phreatophytic tree species, grows well in heavy metal laden industrial sites and is known to accumulate heavy metals. Heavy Metal ATPases (HMAs) are ATP driven heavy metal pumps that translocate heavy metals across biological membranes thus helping the plant in heavy metal tolerance and phytoremediation. In the present study we have isolated and characterized a novel 28.9 kDa heavy metal ATPase peptide (PjHMT) from P. juliflora which shows high similarity to the C-terminal region of P ATPase HMA1. It also shows the absence of the invariant signature sequence DKTGT, and the metal binding CPX motif but the presence of conserved regions like MVGEGINDAPAL (ATP binding consensus sequence), HEGGTLLVCLNS (metal binding domain) and MLTGD, GEGIND and HEGG motifs which play important roles in metal transport or ATP binding. PjHMT, was found to be upregulated under cadmium and zinc stress. Heterologous expression of PjHMT in yeast showed a higher accumulation and tolerance of heavy metals in yeast. Further, transgenic tobacco plants constitutively expressing PjHMT also showed increased accumulation and tolerance to cadmium. Thus, this study suggests that the transport peptide from P. juliflora may have an important role in Cd uptake and thus in phytoremediation.

Capability of the Invasive Tree Prosopis glandulosa Torr. to Remediate Soil Treated with Sewage Sludge

“…On the other hand, the abundance of Pb and Cd, the less concentrated metals in the growth medium independent of the sewage sludge content, were similar among treatments in the leaves and roots, except for Cd in roots for the highest sewage sludge contents. This may be related to the presence of a transport peptide in this species that seems to have an important role in Cd uptake [47]. In contrast, the concentration of Cu, Zn, Cr, Ni, Co, and Fe in leaves and roots increased with the addition of sewage sludge.…”

Spraying Zinc Sulfate to Reveal the Mechanism through the Glutathione Metabolic Pathway Regulates the Cadmium Tolerance of Seashore Paspalum (Paspalum vaginatum Swartz)

“…There are three processes of Cd transport in plants: root absorption, long-distance transport to the aboveground parts, and storage in leaves. Cd and its chelate-related transporters mainly include zinc/iron transporters (ZRT/IRT-like protein, ZIP) [ 61 ], natural resistance-associated macrophage proteins (NRAMPs) [ 62 ], HMAs [ 63 ], metal tolerance proteins (MTP), a cation exchanger (CAX) [ 64 ], an ATP binding cassette transporter (ABC) transporter [ 65 ], and a yellow stripe-like transporter (YSL) [ 66 ]. By analyzing the expression of genes related to Cd absorption and transport, we found that the expression level of most members of ZIP, HMAs, NRAMPs, CAX, YSL, and MTP families was upregulated.…”

Genome-wide Identification and Function Analysis of HMAD Gene Family in Cotton (Gossypium Spp.)

“…Chaperone is an important way in delivering Cu to heavy metal P1B-ATPases [41]. In general, HMA contain approximately 6-8 transmembrane helices, a soluble nucleotide binding domain, phosphorylation domain, and a soluble actuator domain, of which HMA1-4 belonging to Zn 2+ /Co 2+ /Cd 2+ /Pb 2+ transporting, although HMA1 conserved amino acids is different from the HMA2, HMA3 and HMA4 [33], whereas HMA5-8 belong to the Cu + /Ag + subclass [51].…”

“…HMA (Heavy Metal ATPase) belonging to P1B-type ATPases (also called CPx-ATPases), is responsible for ion detoxi cation/transport [32,33,34] and vacuolar compartmentalization [35,36]. It is interesting in double mutant that HMA not only affects the transport of heavy metals [37], but also affect the plant growth and development [34].…”