Membrane-bound pyrophosphatases (PPases) are involved in the adaption of organisms to stress conditions, which was substantiated by numerous plant transgenic studies with H⁺-PPase yet devoid of any correlated evidences for other two subfamilies, Na⁺-PPase and Na⁺,H⁺-PPase. Herein, we demonstrate the gene cloning and functional evaluation of the membrane-bound PPase (CmPP) of the human gut microbe Clostridium methylpentosum. The CmPP gene encodes a single polypeptide of 699 amino acids that was predicted as a multi-spanning membrane and K⁺-dependent Na⁺,H⁺-PPase. Heterologous expression of CmPP could significantly enhance the salt tolerance of both Escherichia coli and Saccharomyces cerevisiae, and this effect in yeast could be fortified by N-terminal addition of a vacuole-targeting signal peptide from the H⁺-PPase of Trypanosoma cruzi. Furthermore, introduction of CmPP could remarkably improve the salt tolerance of tobacco, implying its potential use in constructing salt-resistant transgenic crops. Consequently, the possible mechanisms of CmPP to underlie salt tolerance are discussed.

膜结合焦磷酸酶（PPases）参与生物体适应于应力条件下，这是由许多植物的转基因研究用H证实⁺ -PPase还没有为其它两个亚家族的任何相关证据，钠⁺ -PPase和Na ⁺， H ⁺ -PPase。在本文中，我们证明了人类肠道微生物甲基戊酸梭菌的膜结合PPase（CmPP）的基因克隆和功能评估。所述CMPP基因编码的699的单一多肽的氨基所预测作为一个多跨越膜和K酸⁺依赖性的Na ⁺，H ⁺-PPase。CmPP的异源表达可以显着增强大肠杆菌和酿酒酵母的耐盐性，并且可以通过在克鲁斯锥虫的H ⁺ -PPase的液泡靶向信号肽的N末端添加N端来增强酵母中的这种作用。此外，引入CmPP可以显着提高烟草的耐盐性，这暗示其在构建耐盐转基因作物中的潜在用途。因此，讨论了CmPP增强耐盐性的可能机制。